The presence of a coiled cochlea is a unique feature of the therian inner ear. While some aspects of the cochlea are already known to affect hearing capacities, the full extent of the relationships between the morphology and function of this organ are not yet understood—especially when the effect of body size differences between species is minimized. Here, focusing on Euarchontoglires, we explore cochlear morphology of 33 species of therian mammals with a restricted body size range. Using μCT scans, 3D models and 3D geometric morphometrics, we obtained shape information of the cochlea and used it to build phylogenetically corrected least square models with 12 hearing variables obtained from the literature. Our results reveal that different taxonomic groups differ significantly in cochlea shape. We further show that these shape differences are related to differences in hearing capacities between these groups, despite of similar cochlear lengths. Most strikingly, rodents with good low-frequency hearing display “tower-shaped” cochleae, achieved by increasing the degree of coiling of their cochlea. In contrast, primates present relatively wider cochleae and relative better high frequency hearing. These results suggest that primates and rodents increased their cochlea lengths through different morpho-evolutionary trajectories. These uniquely therian characters include the loss of the lagena macula and the invasion of a laminar bone, which supports the basilar membrane. Perhaps the most remarkable and paleontologically informative change is that the hearing portion of the inner ear has at least one full turn, thus being referred to as the cochlea. It is commonly accepted that this feature is an evolutionary adaptation, which allows for the development of longer cochleae while saving space and providing efficient innervation to the receptor cells5. Since sound-induced organ motion depends on the physical properties of said organs, morphological changes of the auditory structures are expected to result in different perceptual qualities. Several studies have investigated a potential functional relationship between the number of turns and hearing performance in mammals6. These studies argued that an increase in cochlea coiling  is associated with lower hearing limits. This is especially true if the value is multiplied by cochlea length, where large values are associated with better low-frequency hearing. In fact, Mannousaki et al. (2008) provided a model of the curvature of the cochlea that suggests that coiling might enable better sensitivity to low frequencies, by concentrating energy as the sound-induced waves propagate to the region of the cochlea associated with low-frequency sound perception in the apex.Nonetheless, a strong correlation between number of turns and length of the cochlea has not been found7, with the ability of hearing above 10 kHz being a characteristic feature of mammals. Although several bird species can produce vocalizations with harmonics that reach ultrasound, they cannot hear them8. Nonetheless, several anuran species are reportedly able to communicate in the ultrasound10. The mammalian fossil record shows that cochlea elongation and coiling evolved shortly after the three-ossicular chain evolved during the late Jurassic11. While this change in middle ear morphology was an important adaptive change, it alone would not have been enough to attain high-frequency hearing. Based on this, some authors suggest that the elongation of the cochlea developed to achieve an improved high-frequency hearing13. Heffner and Heffner (2008) proposed that this enhanced sensitivity to high frequencies emerged to provide binaural cues associated with sound localization abilities7. As a result, the therian hearing range (in octaves) is greater than in any other tetrapod group including monotremes14. Nevertheless, there is a strong variation in the position of high- and low-frequency limits15. While monotremes still possess a plesiomorphic cochlea, which is uncoiled and retains persistent lagena macula, while also displaying a hearing range that spans for about 3.5 octaves14 most therians possess octave ranges greater than seen in monotremes as evidenced by the extensive collection of audiograms available in the literature  it has been revealed that both the upper and lower limits of hearing shift downward as the size of the animal increases thus showing a distinct allometric effectBased on micro-CT data, we explore the cochlear morphology of 33 species of therian mammals with available audiometric information and with a restricted size range—in order to better control for body mass and interaural distance as main drivers for hearing differences—using landmark-based 3D geometric morphometrics. Additionally, several linear cochlear dimensions  were measured to gain further in-depth insight into the complex anatomy of the bony cochlea.24, a phenomenon called “phylogenetic signal”25, we will employ phylogenetically corrected regressions will be employed to account for this.Based on the previously presented arguments, we expect to find significant associations between cochlear shape and hearing function and hypothesize that highly coiled cochleae will be better adapted for hearing both low- and high-frequencies, resulting in greater hearing ranges. Previous studies have shown the importance of cochlear morphology for its function, and we predict that animals with similar hearing abilities will present similar cochlear anatomy displaying certain degrees of independence from phylogeny. Because complete independence from phylogeny cannot be expected due to shared evolutionary historyOryctolagus cuniculus), 1 scandentian (Tupaia glis), 16 rodents and 12 primates (see Table Hemiechinus auratus) and 2 marsupials  are included. The sampled species range from a body mass of 20 g to 4000 g and an inter-aural distance of 9 mm to 42 mm (Mus musculus and Marmota monax respectively). This size range was chosen based on the definition of “small mammal” given by Bourlière26.We analyzed the ear region of 59 skulls belonging to 33 species of mammals for which hearing information is available. The sample includes 31 therian mammals belonging to the superorder Euarchontoglires: 1 lagomorph (28 (but see29). While a certain degree of sexual dimorphism has been described for the inner ear of humans31, it is not yet known if this applies to other species. Distinct sexual dimorphism of body mass is present in 12 of the 33 species sampled in this study: guinea pigs, chinchillas, prairie dogs, woodchucks, blind mole rats, brown rats, cotton rats, opossums, tarsiers, red ruffed lemurs, and vervets. While it is possible that intersex inner ear variation also occurs in these species, no study has addressed this question. However, as shown in previous shape analysis of the mammalian labyrinth32, interspecific variation in inner ear shape is expected to be larger than intraspecific variation, likely reducing the impact of sexual dimorphism on our results. Furthermore, if present, sexual dimorphism would be minimized in our analyses after average shape values for each species are obtained.The skulls are housed in the Museum für Naturkunde in Berlin  and the Phyletisches Museum in Jena . Each species is represented by one or two skulls . This sample size has been demonstrated to be adequate for morphological studies when there is a large variation in the samplewww.vsg3d.com/avizo) by visually selecting the threshold that best represents the surface of the bony labyrinth. Afterwards, the ‘Isosurface’ module calculates a 3D surface directly from the matrix of grey-scale voxels. The resulting surfaces were saved in the .stl file format, and then used to measure inter-aural distance using the “Measure” tool in Avizo™ between the most superior points of both external auditory meatus.We obtained μCT scans of the skulls using a Bruker™ SkyScan 2211 X-ray Nanotomograph housed at the Max Planck Institute for the Science of Human History . The scans were employed to generate 3D surfaces using Avizo Fire 9™ . Right ear structures were used when possible and mirrored left ones if necessary. Additionally, adult body mass values were obtained from the PanTHERIA database57.Following this, and as described in Janssens et al.Using Avizo Fire 9™, a single researcher (JdR) digitalized landmarks and semilandmarks of curves on the oval window (OW) and the cochlea. As the shape of the OW was not analyzed, the relative landmark position was not important, i.e., it was not necessary for the position and number of landmarks to be homologous.58 using the “equidistantCurve” function of the Morpho package59. Landmarks coordinates were exported as .landmarkAscii files and then transformed into .TPS files. Landmarks allows us to describe the position of anatomical structures that are easily identified in all species as homologous60, while semilandmarks facilitates the description of curves or surfaces where no anatomical landmarks can be placed.The landmarks placed on the cochlea were positioned using anatomical characteristics of the inner ear. The first and second landmark were placed at the basal end of the coiling, at the most superior and inferior points of the round window, respectively. Then, an arbitrary number of equidistant semilandmarks were placed following the outermost side of the cochlea until reaching the apex, where the last landmark was placed. Since the same exact number of landmarks is needed to proceed with the geometric morphometric analysis, the semilandmarks were later automatically resampled to 127 semilandmarks along each cochlea . Shape differences between the different inner ears were analyzed by performing a Principal Component Analysis (PCA) and on the covariance matrix of the Procrustes shape coordinates. The PCA allows us to describe changes in shape by highly reducing the dimensionality of the dataset by recognizing which of the axes  explain most of the variance63. To test if cochlea shape is related to the phylogenetic structure of our sample, phylogenetic signal was calculated. Because of shared evolutionary history, closely related species tend to be more similar to each other than to distant related ones25. This tendency is named phylogenetic signal, and can be estimated in several ways. Here, we employed Blomberg’s K25 for the first 3 principal components individually (accounting for 90% of shape variation), and its multivariate version Kmult64. K values close to 0 indicate no phylogenetic signal, values close to 1 indicate that the amount of variation present is expected under a Brownian motion model of trait of evolution, and values above 1 indicate that closely related species resemble each other more than would be expected under Brownian motion. Because our sample is phylogenetically structured, a Phylogenetic Principal Component Analysis (pPCA) was also performed to control for phylogenetic covariance65, which is achieved by inversely weighting the covariance matrix by phylogeny. Through this method, shape differences between taxonomic groups are maximized, which makes the identification of their particular shape characteristics simpler.First, the consensus shape (defined as the set of average coordinates for a species) was obtained for all of the species for which more than one specimen was analyzed. To remove any non-shape difference—that is, location, orientation, and scale, from the landmark configurations—a Generalized Procrustes Analysis was performed afterwards, thus allowing us to analyze shape variation alone. All 3D-Geometric morphometric analyses were performed in R using the Morpho and geomorph4 and measured the following way: the cochlea surface was rendered in Avizo™ and placed with the apex pointing towards the viewer. Finally, a circle divided into ten equal triangles was drawn on top of the last turn, in order to precisely count the amount of turns in incremental 1/10ths , and oval window area (OWA). Secondly, line-sets were created from each of the individual landmark configurations and saved in .lineset files. These line-sets consist of a continuous line connecting all the landmarks and semilandmarks belonging to a specimen and can be used to create a view of the associated μCT slice, which is perpendicular to this line. This way, we acquired CT images of 130 perpendicular cross-sections of the cochlea and measured the area of five of them using Avizo™. In order to allow interspecific comparisons of cross-sectional area of differently shaped cochleae, the CT images of these five cross-sectional areas were defined by dividing cochleae into four parts along its length by selecting a slice at 1/5th–5/5th of its trajectory, were then used to calculate the average cross section (ACS) of the cochlea, and the first and last one for the ratio (CSR) between the area at base and the apex. The number of cochlear turns (NT) was obtained starting from the inflection point at the round windowCochlea width (CW) was obtained in Avizo by directing the apex of the cochleae down and aligning the modiolus to 90°, so that it was vertical on the screen. We then proceeded to acquire the μCT slice located immediately inferiorly to the round window. As shown in Fig. 66 and later used to build a phylogenetic tree . PGLS accounts for the non-independence of related species due to shared evolutionary history by modelling the covariation in the regression error term using the phylogenetic information and assuming a Brownian Motion model of trait evolution. Mann–Whitney U tests were performed between groups to check whether the difference between their means were statistically significant (P < 0.05). All morphological measures, with the exception of cross-section ratio, were log10 transformed.Phylogenetic information, including divergence times, was obtained from TimeTreeree Fig. . The phy68. By employing the “contMap” function of the phytools package for R69, we reconstructed the changes in cochlear shape along its evolutionary history for our sampled species.By employing a phylogenetic tree and information about biological traits associated to the tip taxa on it, it is possible to estimate character states for ancestors71.All analyses were performed using the software R, and the Morpho, geomorph, caper, geiger and picante packages72. Because our dataset mostly consists of behavioral audiograms obtained using speakers, we had to correct thresholds of ABR audiograms to incorporate them in our analyses. To do so, we first computed correction factors as threshold differences between ABR and speaker-based behavioral audiograms of Lemur catta and Nycticebus coucang, at 11 different frequencies between 1 and 32 kHz  remain much lower than the average difference observed between ABR and behavioral audiograms (11.4 [5.4–26.1] dB), in particular below 4 kHz (18.3 [10.5–26.1] dB). This suggests that incorporating uncorrected ABR audiograms in our analyses would have led to higher error levels than using the correction factors we propose. Additionally, analyses were performed in which species that were represented by ABR data were left out to test if results change. The results did not change significantly for most of the data set, however, with the exception of high frequency cut-off. Nonetheless, high-frequency cut-off values do not change between ABR and behavioral audiograms, and we believe this difference in results is caused by the reduced sample size. PGLS regression values can be seen on supplementary Table In order to explore the potential relationships between cochlea parameters and its associated hearing ability, audiometric data were obtained from various sources in the literature Table . Behavio73: low frequency cut-off (LFC), average sensitivity between LFC and 1 kHz (ASL), average sensitivity between 1 and 8 kHz (ASM), high frequency cut-off (HFC), average sensitivity between 8 kHz and HFC (ASH), sensitivity at 1 kHz (SPL1), range of octaves (RO), total mean sensitivity (MS), peak sensitivity(PS), characteristic frequency 1 (CF1), and characteristic frequency 2 (CF2).A total of 11 different hearing variables were extracted from the audiometric data, mostly following ColemanVarecia rubra and Hemiechinus auratus-. In cases where the last frequency tested reached 45 dB SPL or more, the frequency value at 60 dB SPL was extrapolated  were set to 60 dB SPL and used to calculate the range of octaves as well (RO). Some species do not have data available for the lower hearing limits because the original audiometry did not test for such frequencies; -the upper limit is also missing in the case of 74 defined as the average threshold for half-octave steps between the target frequencies. When species showed two peaks in hearing sensitivity , both frequencies were extracted as characteristic frequency 1 for the lowest one and characteristic frequency 2 for the highest, but only the lowest dB SPL value of the characteristic frequencies was used for peak sensitivity. To compare the species presenting only one peak (“V” shaped audiogram), the frequency where sensitivity is highest was used for both characteristic frequency 1 and characteristic frequency 2. This has been done since it is unknown if this single peak is homologous to either characteristic frequency 1 or characteristic frequency 2, respectively. The complete dataset, including both morphological and audiometric data, can be found in the supplementary Table Average sensitivities were calculated following Ramsier75, and has already been observed when analyzing inner ear shape76.The first principal component (PC 1) accounts for ca. 54.5% of the variation in cochlea shape, PC 2 for ca. 23.3%, and PC 3 for ca. 12.3% , indicating that the differences between taxa are close to what would be expected under a Brownian motion of trait evolution. On the other hand, signal for overall shape (first 3 PCs) shows values between 0 and 1 (Kmult = 0.52), while low phylogenetic signal was estimated for PC 2 and PC 3 (K = 0.48 and K = 0.30 respectively), indicating than closely related species resemble each other less than expected under Brownian motion. The results of the phylogenetic PCA allowed us to identify the trait differences that characterize the main taxa in our sample .To further explore what the changes in PC score entail, multiple linear models were created against obtained morphological variables Table . CochleaP < 0.01), and a slightly stronger one with centroid size , indicating a small, albeit significant degree of allometry.A multiple regression using cochlea shape (first 3 PCs) shows a significant association with body mass , but the respective scatterplot . In contrast, rodents exhibit a strong correlation . Nannospalax ehrenbergi and M. unguiculatus have longer cochleae than the rest of Myomorpha, a similarity with Sciuromorpha and Hystricomorpha. Carlito syrichta shows a longer cochlea than the rest of the primates, displaying a similar length as Aotus trivirgatus and C. aethiops despite a much smaller body mass. The cochleae of both marsupial species, T. elegans and D. virginiana are short relative to their body mass; this is also true for H. auritus. On the other hand, O. cuniculus and T. glis show a relationship between both variables that is similar to the one for primates and sciuromorphs and hystricomorphs, resembling their positions on the PCA of shape.PGLS linear models were created to explore how cochlear variables change in relation to body mass in the sampled species. The regression between cochlea length and body mass is highly significant . Nonetheless, the primate regression line falls above the one for rodents indicating that most primates have a wider first cochlea turn for the same body mass . Using the low-frequency cut-off values to color the points in the PCA plot , while the second and third do not. An independent regression for each group results in no correlation for PC1 with low frequency cut-off in primates, but a strong correlation in rodents  is a strong predictor for low-frequency cut-off , and an increase in number of turns is associated with a decrease in the low-frequency limits of hearing. Nonetheless, primates present consistent low-frequency cut-off values regardless of coiling. Hemiechinus auratus, while presenting the lowest amount of turns of the whole sample, shows relatively low hearing limits. PC2 is associated with changes in cochlear width. Accordingly, the PGLS models between cochlea width and low frequency cut-off exhibit comparable results to the ones obtained using PC2 as a predictor, albeit slightly stronger . Sciuromorpha and Hystricomorpha present longer cochleae than Myomorpha, with the exception of N. ehrenbergi and M. unguiculatus. Their lengths are also comparable to those of primates, with their averages showing no significant difference from them, but the aforementioned rodents present lower hearing limits . In contrast to what was obtained for low frequency cut-off, PC1 and PC2 display similar degrees of association with sound pressure level at 1 kHz (P < 0.001 and P < 0.001 respectively). Changes along neither PC1 or PC2 are related to changes in sound pressure level at 1 kHz for primate species, while changes along PC1 seem to be greatly associated to hearing performance changes within rodents, mainly between Hystricomorpha and Sciuromorpha and Myomorpha. In addition, N. ehrenbergi and M. unguiculatus display similarities to Hystricomorpha and Sciuromorpha, while M. auratus and R. norvegicus show lower sound pressure level at 1 kHz values than the rest of Myomorpha, resembling primates. Sound-pressure level at 1 kHz produces similar results to low frequency cut-off for the rest of the variable set: cochlea length, cochlea width, number of turns and oval window area remain the best predictors for this hearing variable. We found that cochlea width is the best sound-pressure level at 1 kHz predictor of the variable set . In addition, average cross-section now becomes a significant predictor, although with a R2 and p value considerably lower than the rest of the variables .Seven species of primates in our sample lack information about the low frequency cut-off present in the literature. In order to garner insight on hearing capabilities on the low frequency hearing of these species, sound pressure level at 1 kHz was employed. In this regard, the first 3 PCs show a strong correlation with sound pressure level at 1 kHz . N. ehrenbergi was left out for all further analysis regarding high frequency cut-off due to its highly specialized hearing capabilities. As expected, the number of turns shows a relationship with high frequency cut-off that is similar to the one we found for PC 1, where an increase in coiling is associated with lower limits  reveals no correlation with high frequency cut-off, and the removal of P < 0.001, and ca. 78%, P < 0.001 respectively). Finally, only oval window area from the non-shape morphological variables shows a significant association with high frequency cut-off when using the complete sample, albeit the fit is not strong  followed closely by cochlea length . Most of the shape association with range of octaves was related to PC1 . Number of turns showed similar results, where an increase in coiling was related to larger hearing ranges. Although body mass was not a good predictor, all size related variables showed strong associations with range of octaves, with the exception of average cross-section area. In all cases, an increase in structure size was associated with increased hearing ranges.Cochlea shape was the strongest predictor for range of octaves , but none with characteristic frequency 1. Nevertheless, no morphological predictor showed a particular strong correlation with either, and the strongest association found was with oval window area for characteristic frequency 2 . On the other hand, peak and mean sensitivity produced no significant results.Cochlea shape showed a significant correlation with characteristic frequency 2  possess a distinct higher number of turns and are thus similar to sciuromorphs and hystricomorphs in this shape aspect. The fact that all of the analyzed species belonging to Hystricomorpha and Sciuromorpha present highly coiled cochleae might suggest that this feature originated early in their evolutionary history, and that the myomorphs M. unguiculatus and N. ehrenbergi obtained this feature convergently. We reconstructed ancestral states in order to test this theory, and the results appear to support it  of cochlear shape variables shows the greatest separation between rodent suborders along PC 1, with Myomorpha having mainly negative PC 1 values (= lower number of turns) and Sciuromorpha and Hystricomorpha on the positives (= higher number of turns). Several primate species belonging to Haplorhini, are also associated with this shape. However, two species of Myomorpha , sensitivity to high frequencies and the upper hearing limit are not. The removal of N. ehrenbergi from the analysis—a hearing specialist, with especially low high-frequency cut-offs48—results in a significant regression, but only if rodents are analyzed separately. As with cochlea length and oval window area an increase in the degree of coiling in rodents is associated with a lower high-frequency cut-off. Thus, we found no evidence to support the idea that a high number of cochlear turns is an evolutionary adaptation to achieve better high-frequency hearing. Rather, our findings suggest that a lower number of turns is related to better high frequency hearing, as was previously found for other mammalian groups78. Our results also strongly support the assumption that a higher degree of coiling is directly related to improved low frequency hearing capacities as previous work has suggested22.Cochlear coiling  and cochlear duct lengthening are unique morphological features of therian mammals. While previous studies found no correlation between cochlea length and number of cochlea turns80. Furthermore, the cochlear shape displayed by most primates is characterized by an enlarged basal turn, and appears to be related to a relatively better high frequency hearing. This may be so, as the first section of the cochlea is associated with the relatively stiffer portion of the basilar membrane, it codes the perception of high-frequency sounds80. O. cuniculus resembles strepsirhine primates in several ways, as showed by the PCA of shape: mainly in its cochlear width and amount of cochlear turns. Furthermore, its hearing capabilities are also comparable to most primates, with good low-frequency hearing but slightly worse than hystricomorphs and sciuromorphs, and high frequency hearing capacities that are not as good as those of most myomorphs, but remarkably better than those of hystricomorphs and sciuromorphs. Our finding strongly corroborate the results of a number of prior studies, where a relatively enlarged basal turn is related to an improved high frequency hearing, and examples can be found in a diverse number of mammalian taxa78. Despite these findings, the ratio between the area of the cross-section at the base and apex of the cochlea did not yield any interesting results, and while the average cross-section area performed well as a predictor for a few hearing parameters, the results highly resemble those obtained for body mass.For a given body size, primates have cochleae of similar length to those of Sciuromorpha and Hystricomorpha. However, instead of a high degree of coiling they display an enlarged basal turn, which results in a flatter, disc-shaped cochlea. This becomes particularly evident when cochlea width relative to body mass is considered, with primates displaying generally relatively wider cochlea. These differences are reflected in the hearing capacities, with primates showing less sensitivity to low-frequency sounds but a slightly increased sensitivity to high frequencies. As these groups have good low frequency hearing when compared to myomorphs, we argue that this was achieved by an increase in cochlea length. We additionally propose that the high degrees of coiling observed in hystricomorphs and sciuromorphs evolved to enhance this ability even further by expanding the terminal end of the cochlea. We base this on findings showing that the final section of the cochlea houses the most compliant section of the basilar membrane, associated with the perception of low frequency soundsA visual analysis of the cross-section of the cochleae employed in our analysis reveals that the first turn of the cochlea in primates is oriented approximately within the same plane as the second turn. Additionally, the first turn is relatively from the rest of the cochlea . Tarsiers are nocturnal primates capable of communicating using very high frequencies, perhaps giving it an advantage when hunting ultrasound-producing arthropods82 and explaining its enhanced hearing abilities. Nannospalax ehrenbergi and M. unguiculatus are also particularly interesting, as they have longer cochleae and a greater number of turns than other myomorphs, a feature that they notably share with scuiuromorphs and hystricomorphs. They also share similar hearing capacities, in particular they have good low-frequency hearing, supporting our hypothesis that highly coiled cochleae evolved to obtain an enhanced sensitivity to low frequency sounds by expanding the terminal section of the cochlear duct. These two species are highly adapted to their lifestyles: the highly fossorial N. ehrenbergi lives most of its life underground, a one-dimensional environment where sound localization is nearly irrelevant promoting good low-frequency hearing48. Meriones unguiculatus has particularly good hearing for both high and low frequency sounds45, and is noticeable capable of emitting very low “drumming” sounds using its hind limbs83. The cochlea of the T. glis resembles the cochleae of most sciuromorphs and hystricomorphs, as it presents a large amount of turns (~ 2.75), but its width is greater than most rodents belonging to those groups. Its position on the PCA of shape is close to that of G. seneglasensis and N. ehrenbergi, and it also shares a similar inter-aural distance with the last one, which is significantly smaller than all primates, sciuromorphs and hystricomorphs. The hearing capabilities of the treeshrew are reflected on these particular features, as it has good low frequency hearing when compared to most species of similar size while also having good high frequency hearing.An outlier in our study is N. ehrenbergi, M. unguiculatus, C. syrichta and D. madagascariensis which have similar values). Body size is the main factor driving changes in oval window area, but our analysis also revealed that species with greater oval window areas also exhibit a greater number of cochlear turns. It has previously been described that larger middle ear structures are associated with better low frequency perception85 due to reduced stiffness73, which is supported by our findings. A number of studies have additionally found shared traits between species of fossorial mammals, which include an enlarged stapedial footplate, and conversely a large oval window88. Our findings provide support to these articles, which focused their analyses on middle-ear structures and provided evidence that animals with fossorial habits present a low ratio between the areas of the tympanic membrane and oval window. Nonetheless, it is unknown if both highly coiled cochleae and large oval windows are required to lower the low-frequency limits of hearing, and whether or how these variables interact.While oval window area increases with body size in our sample, Sciuromorpha and specially Hystricomorpha present significantly larger oval window areas than most other species in the sample (except for Finally, our results show that high-frequency hearing parameters are difficult to predict when using inner ear morphology alone. In fact, only the oval window area was significantly correlated when using the whole species sample to build the PGLS regression models. Since the oval window acts as the intersection between the middle ear and the inner ear, these results indicate that the transmission capacity of the middle ear may play a more important role when predicting high frequency sound perception than inner ear structures.Cochlear shape significantly relates to hearing performance in a sample of therian mammals where size range is limited. While the length of the cochlea is a significant predictor of hearing capacities, similar length values in similar sized mammals can be achieved through different shapes depending on the taxon. Most primates have similar cochlea lengths when compared to rodents of similar body size belonging to Sciuromorpha and Hystricomorpha. In contrast, primate cochleae are less coiled, and primate are wider and flatter with an enlarged basal turn. This might explain their higher sensitivity to high-frequencies, as the first section of the cochlea is associated with the stiffer portion of the basilar membrane and the perception of high-frequency sounds. On the other hand, the rodents belonging to the aforementioned groups present highly coiled cochleae and their hearing abilities seem mainly focused on perceiving low-frequency sounds, suggesting that their cochleae elongated by expanding at the apical region resulting in more cochlear turns.M. unguiculatus and N. ehrenbergi have relatively long cochleae for their body size, with a high degree of coiling. Their hearing abilities are in fact similar to those of sciuromorphs and hystricomorphs, with a hearing range leaning towards the low frequencies.Almost all myomorphs in our sample have cochleae that are less coiled than in the other taxa, although several exceptions among them seem to confirm our previous assumptions: Supplementary Information.


This article comments on:Batyrshina ZS, Shavit R, Yaakov B, Bocobza S, Tzin V. 2022. The transcription factor gene TaMYB31 regulates the benzoxazinoid biosynthetic pathway in wheat. Journal of Experimental Botany73, 5634–5649. JXB, TaMYB31 in the tetraploid wheat Triticum turgidum and verified its function as a component of BXD metabolism in the hexaploid wheat Triticum aestivum, where it regulates constitutive and stress-inducible BXD biosynthesis.Benzoxazinoids (BXDs) are abundant indole-derived specialized metabolites in several monocot crop species, such as wheat, maize, and rye. They function in plant immunity against herbivorous arthropods and fungal pathogens, but also as iron chelators, in metal tolerance, and as allelochemicals. Although BXD biosynthetic pathways have been studied extensively and are well described, information about the transcriptional regulation of BXD biosynthesis is scarce. In the current issue of Bx genes has not been comprehensively investigated. So far, just a few transcription factors were described in regulating BXD biosynthesis in maize and none was functionally determined in wheat  to identify transcription factors up-regulated in response to insect herbivory  based gene silencing system (VIGS) in seedlings of the hexaploid wheat Triticum aestivum. Silencing of TaMYB31 resulted in decreased basal and herbivore-inducible levels of several BXDs, thus verifying a functional role for this transcription factor in BXD biosynthesis. Moreover, TaMYB31-silenced seedlings were more susceptible to insects from different feeding classes, including the bird cherry-oat aphid Rhopalosiphum padi, larvae of the Egyptian cotton worm Spodoptera littoralis, and the two-spotted spider mite Tetranychos urticae, confirming the broad role of BXDs in plant immunity against herbivores and the involvement of TaMYB31 in their biosynthesis.The biosynthesis of BXDs is induced upon insect infestation  potentially functioning in BXD biosynthesis in wheat. Thus, they constitute promising candidates for additional regulation of BXD metabolism in wheat.Due to the various functions of BXDs in agriculturally relevant crops, their biosynthetic pathways have been the subject of extensive research, and understanding the regulatory networks which underlie BXD metabolism holds great potential for the development of novel strategies for crop protection and pest management. Biosynthesis of BXDs has mainly been investigated in maize. Therefore, several enzymes involved in BXD synthesis have only been described in maize, but their orthologs in wheat have not been identified yet  Zhou et. MoreoveSpodoptera exigua. Upon PEP perception, maize plants activate a vast array of immune responses, including induction of BXD metabolism  in BXD metabolism in wheat and maize, highlighting the regulatory role of JA in stress-inducible plant metabolic pathways (tabolism . A simil


Hearing is essential for the processing of acoustic information and the understanding of speech signals. Hearing loss may be associated with cognitive decline, depression and reduced functionality.To analyze the prevalence of hearing complaints in elderly individuals from Rio Grande do Sul and describe the profile of the study participants with and without hearing complaints.7315 elderly individuals interviewed in their homes, in 59 cities in the state of Rio Grande do Sul, Brazil, participated in the study. Inclusion criteria were age 60 years or older and answering the question on auditory self-perception. For statistical purposes, the chi-square test and logistic regression were performed to assess the correlations between variables.139 elderly individuals who did not answer the question on auditory self-perception and 9 who self-reported hearing loss were excluded, totaling 7167 elderly participants. Hearing loss complaint rate was 28% (2011) among the elderly, showing differences between genders, ethnicity, income, and social participation. The mean age of the elderly without hearing complaints was 69.44 (±6.91) and among those with complaint, 72.8 (±7.75) years. Elderly individuals without hearing complaints had 5.10 (±3.78) years of formal education compared to 4.48 (±3.49) years among those who had complaints. Multiple logistic regression observed that protective factors for hearing complaints were: higher level of schooling, contributing to the family income and having received health care in the last six months. Risk factors for hearing complaints were: older age, male gender, experiencing difficulty in leaving home and carrying out social activities.Among the elderly population of the state of Rio Grande do Sul, the prevalence of hearing complaints reached 28%. The complaint is more often present in elderly men who did not participate in the generation of family income, who did not receive health care, performed social and community activities, had a lower level of schooling and were older. Hearing is essential for the processing of acoustic information and for the production and understanding of speech signals. The consequences of hearing loss vary according to its type, degree and age of onset. In adults and elderly individuals, one generally observes isolation, with diminished participation in social and family life, sometimes due to the fear of becoming the target of ridicule or contempt.Because of the increase in the numbers of the elderly, it is appropriate to understand the factors related to aging and frailty, especially factors related to becoming incapacitated.Therefore, it is important to evaluate the functional capacity of the elderly in order to correlate it with the practical aspects of personal care in the maintenance and performance of the basic and complex activities of daily living.Hearing loss diagnosis and rehabilitation should be carried out early after recognition, regardless of the individual's age. However, in many cases the hearing loss occurs gradually, with a slow progression that is not noticed or is neglected.Despite the relevance of hearing loss in the elderly, few studies have been carried out or been able to determine its incidence in the Brazilian population or in their states. One existing study carried out in São Paulo showed a prevalence of 30% of hearing loss in the elderly population.Therefore, this study aims to analyze the prevalence of self-reported hearing complaints in elderly individuals from the state of Rio Grande do Sul, Brazil and to describe the epidemiological factors associated with elderly individuals with and without hearing complaints.This was characterized as a descriptive and cross-sectional study, which is part of a larger survey, with focus on hearing function of the elderly. The questionnaire was inspired by the Global Age-friendly Cities: A Guide, of the World Health Organization. The analyzed and discussed data were collected between the years 2010 and 2011.In total, 7315 elderly individuals were interviewed in their homes, randomly selected from census sectors of 59 cities in the state of RS. Inclusion criteria were age of 60 years or older and attending the interview. Participants who could not answer the question on auditory self-perception due to cognitive and communication impairment were excluded. All participants or their guardians signed the free and informed consent form. The project was approved by the ethics committees of the institutions involved in the study (09/04931 and 481/09).Among other issues the elderly were interviewed, about hearing perception. The variables gender , marital status , ethnicity , participation in family income , received care for health problems in the last 6 months , performs social  or community activities  and reports difficulties going out due to communication problems  in addition to hearing aid use  were treated as categorical variables and expressed as frequencies. Age and educational level , these were treated as numerical variables and expressed as mean and standard deviation. The question about hearing self-perception had the following response options: “excellent”; “good”; “regular”; “poor” and “very poor” – previously established in the questionnaire.For the statistical analysis, auditory self-perception levels of good or excellent were grouped together, as were without complaint and regular, and poor or very poor. The chi-square test was used to test the association between hearing complaints and the other variables. Multiple logistic regression was used to calculate the odds ratio of hearing loss complaint being influenced by the assessed variables. Significance levels lower than 5% were considered statistically significant and between 5% and 10%, as indicative of significance.Of the 7315 participants, 139 were excluded because they did not answer the question about auditory self-perception (cognitive impairment) and 9 because they reported hearing loss, leaving 7167 elderly individuals in the sample . The resAt the logistic regression analysis, both age and educational level maintained almost the same level of significance. Regarding the years of study, the results showed that participants with hearing complaints had fewer years of study. Each extra year of study was related to 3% lower chance of hearing complaints. In relation to age, each extra year was related to a 6% higher chance of hearing complaints .Table 2Rp = 0.0016). The association between gender and hearing complaints remained significant in the multivariate analysis, after adjusting for other variables. Although the difference in the frequencies found in men and women with complaints was only 3.3% (p < 0.0001). Single and widowed individuals had the highest frequencies of hearing complaints, with the lowest being observed in married and separated individuals.The hearing complaints were significantly more frequent in men  . HoweverMost participants did not engage in social or community activities, but both activities were significantly correlated with hearing complaints both in the simple analysis and after adjusting for other variables. Those who attended such activities showed higher frequency of complaints when compared to those who did not participate. This can be explained considering that individuals who are exposed to some activities can perceive their worse hearing performance than others who are not exposed to them, i.e., at home or in a familiar environment that adapts to them.People who reported not leaving the house due to communication difficulties comprised only 0.8% of the sample , but thiOf 2011 elderly individuals who reported hearing complaints, only 8% used a hearing aid . Most ofThe incidence of self-reported hearing loss in our sample of elderly individuals aged 60 years and older was 28%, similar to another population-based study carried out in São Paulo, which showed a prevalence of 30%.Population-based studies on hearing loss are not common, either in Brazil or in other countries. Only a few studies were found on this topic. One of them, a literature review that pooled samples from European countries with individuals aged 60 years or older, found that approximately 30% of men and 20% of women had some degree of hearing loss at 70 years of age, as well as 55% of men and 45% of women at age 80.The influence of years of schooling can be observed in the assessed data, as the higher the educational level, the lower the chance of having a hearing loss complaint. A similar result was observed in studies in both BrazilianWhen assessing the question about receiving health care and having hearing loss, it was observed that the elderly who received such care had fewer complaints. It is believed that such occurrence is due to the fact that individuals without hearing complaints seek health care, when compared to those who do not study, or those who receive health care may be getting some counseling/treatment for hearing loss prevention. This can also be explained by the fact that individuals may be receiving information on hearing loss in the elderly from other professionals. Additionally, elderly individuals may be experiencing conditions that are common in the assessed population and may have hearing loss as a consequence, such as diabetes, hypertension, dyslipidemia, among others.Pandhi et al.We found a significant association between social activity, including physical activity, and hearing loss in the elderly. Another study showed no significant association between physical activity and hearing loss complaints.Corroborating the findings of our study, Chen et al.About the self-reported ethnicity  and the association with hearing complaints, the difference was not statistically significant between the groups in our study. However, a greater tendency of complaints was reported among blacks, followed by mixed-race and white individuals. We must emphasize the fact that the proportion of non-white individuals is much smaller in the state of Rio Grande do Sul when compared to other states of Brazil, with this fact being a reason for not achieving the recommended level of significance. This finding differs from those found in a North-American study, in which the black ethnicity in the elderly was considered significantly protective against hearing loss.We found that older individuals who self-report hearing complaints prefer not leaving the house due to communication difficulties, but a similar study did not show the same results. It analyzed social isolation and its association with hearing loss and found that a greater degree of hearing loss was associated with increased chances of social isolation only in women aged 60–69 years, whereas this association was not significant in other age ranges and in men.We observed that only one-third of the individuals who used a hearing aid did not mention hearing complaints, thus inferring that the hearing aid fully meets their hearing needs. Lack of adjustments or inadequacies could explain the percentage of individuals with hearing complaints even while using a hearing aid.While the numbers of this study enlighten us about the issues regarding hearing loss, it is clear that very little has been done about it. Among our population, we found that only four subjects received audiology follow-up and 54 used hearing aids. Also, we suggest a population-based study with an instrumental hearing assessment, since it is believed that the number of elderly with complaints is lower than the number of those who actually have some degree of hearing loss, considering that hearing loss is progressive (making it easier for the elderly to adapt to the loss), that few of them perform social activities  and that most do not receive health care monitoring.We emphasize the importance of implementing longitudinal follow-up studies of elderly patients with hearing loss complaints, so that we can establish different treatment options, aimed not only at the treatment, but also at more effective prevention in this ever-growing population, especially regarding its clinical, physical, functional and psychosocial aspects.Our study clearly shows that there is a prevalence of approximately 30% of hearing loss complaints among the elderly. The hearing complaint is observed more frequently in men with fewer years of schooling. The chance of having hearing complaints increases with age: for every extra year of age there is an increase of 6% in the chance of hearing loss complaint. The complaint was associated with decreased access to health care and not leaving the house due to communication difficulties. On the other hand, elderly individuals with higher levels of social activity had a higher frequency of hearing complaints.The authors declare no conflicts of interest.


To present recommendations for the coordinated evaluation and management of the hearing and reconstructive needs of patients with microtia and aural atresia.A national working group of 9 experts on microtia and atresia evaluated a working document on the evaluation and treatment of patients. Treatment options for auricular reconstruction and hearing habilitation were reviewed and integrated into a coordinated care timeline.Recommendations were created for children with microtia and atresia, including diagnostic considerations, surgical and non-surgical options for hearing management and auricular reconstruction, and the treatment timeline for each option. These recommendations are based on the collective opinion of the group and are intended for otolaryngologists, audiologists, plastic surgeons, anaplastologists, and any provider caring for a patient with microtia and ear canal atresia. Close communication between atresia/hearing reconstruction surgeon and microtia repair surgeon is strongly recommended. The primary authors  wrote a draft of the manuscript with additional input provided by the contributing authors in specific niche interests and practice areas. A final consensus was obtained on the management recommendations reviewed and approved by all contributors.Microtia is a congenital malformation of the outer ear or pinna whereby the ear is reduced in size, has underdeveloped landmarks, or is misshapen . MicrotiMicrotia occurs in about 1 in 10,000 births, though rates vary depending on ethnic background . In non-Deficiencies of the ear canal, also called aural atresia, are often present with microtia. Varying degrees of aural atresia can be classified from Type A (Stenosis), in which both the fibrocartilaginous and bony parts of EAC are present but narrow, to Type B , in which only some part of the fibrocartilaginous or bony EAC is present with the tympanic membrane being missing or rudimentary, to Type C , in which both fibrocartilaginous and bony parts of the EAC as well as the tympanic membrane are absent . In mostHistory: Clinicians should perform a complete history including ear infections, speech and language milestones, and family history of hearing loss and ear anomalies.Physical exam: A complete physical exam of the infant should be performed looking for associated syndromic findings . It is aHearing evaluation: When infants present with microtia and aural atresia, the involved ear(s) will typically fail the newborn hearing screen (NHS). Regardless of the NHS results, these infants should be referred directly to an audiologist to undergo an outpatient diagnostic Auditory Brainstem Response (ABR) test . NewbornA diagnostic ABR should be performed as early as possible. The Early Hearing Detection and Intervention (EDHI) program goals recommend a diagnostic ABR by 3 months of age. For clinics and centers meeting this metric, they should strive for a diagnostic ABR by 2 months of age . At a miIn most infants from birth to up to 6 months of age, this diagnostic ABR can be done while the infant is sleeping without sedation . Beyond In cases of bilateral microtia and atresia, patients should be referred to audiology as early as possible. Diagnostic audiological assessment should be completed by 2–3 months of age and the infant provided with hearing amplification by 4 months of age and enrolled in early intervention (EI) by 3–6 months of age to optimize speech and language development.Imaging studies: A CT scan of the temporal bone is not recommended in the newborn period. CT should be reserved for just before hearing reconstructive surgical options are discussed  or if there is a concern for cholesteatoma. A high-resolution CT scan of the temporal bone without contrast is recommended before any microtia reconstruction to assess candidacy for atresia repair and to rule out the presence of canal or congenital middle ear cholesteatoma , though Consultations: Newborns should be referred to audiology and otolaryngology to consult on the child's hearing status. In addition, a genetics referral is recommended if the child appears to be syndromic at birth , 2. Theswww.earcommunity.org) to minimize feelings of isolation and provide positive examples of how children with microtia and atresia can grow to be productive, healthy adults.Parents of a newborn with microtia may experience intense emotions, especially guilt and frustration. It is important to counsel parents on theoretical causes of microtia, the hearing impact and then guide them on hearing and reconstructive options and timelines. In most cases, the cause of microtia and atresia is not known. Parental self-blame should be mitigated to the extent possible. Advising parents on ways to talk to the affected child, friends, acquaintances, or other family members about the patient's “little ear” is also paramount to prevent feelings of shame. Families should be encouraged to explore support groups or online communities and forums  on the side of the microtic ear. The hearing loss is confirmed at the time of the diagnostic audiologic evaluation. Amplification options for children with microtia and atresia can be non-surgical or surgical. Before the age of five years, the non-surgical amplification option is recommended as some surgically implanted device options are approved by the FDA for children of age five years and over.A variety of worn hearing devices are available to help children with the conductive hearing loss associated with microtia and atresia . Bone counilateral microtia/atresia, where the non-microtic ear has normal hearing, a device consultation with a pediatric audiologist to discuss bone conduction options and encourage early use to facilitate early adaptation to hearing aid use. Although children under three years old are seldom exposed to challenging hearing environments, it is the experience of most centers that successful use of bone conduction aids in school-aged children correlates with earlier fitting and adaptation. Parents should be made aware that they may not notice a behavioral difference in the early fitting of bone conduction aids, and some may feel that it “doesn't make a difference.” The goal of the early fitting is early adaptation to amplified sound for sensory integration into the child's experience in preparation for school age. While there is an increasing body of literature that indicates that the lack of sound localization in children with unilateral hearing loss is associated with increased difficulties with speech recognition in noise often found in the typical classroom environment  and the magnetic systems  have a similar osseointegrated implant in the skull, but each allows the sound processor to connect to the implant differently. The abutments penetrate the skin, while the magnetic systems do not.The abutment type  are currently FDA approved for patients 12 years of age and older. At the time of this writing, successful implantation in younger patients has been reported both in and outside of the United States  is planned, these surgeries can be done concurrently.If a family is proceeding with alloplastic ear reconstruction, the osseointegrated hearing implant can be placed simultaneously with the alloplastic reconstructive surgery or three months after the ear has healed. For autologous cartilage repair, the implant can be placed concurrently during the stage of surgery in which the newly constructed ear is elevated, which allows access to the posterior auricular region through the same incisions. Alternatively, the osseointegrated hearing implant can be safely placed three months after the final stage of autologous cartilage repair.®, Ponto) can offer a similar pure-tone average as those worn with an implanted magnet (BAHA Attract®). However, implanted active bone conduction devices  provide better high-frequency gain , a tympanic membrane, lining the neo-tympanum and EAC with squamous epithelium, and liberation or reconstruction of the ossicles of the middle ear. Although parents frequently hope that hearing can “be restored” with this surgery, it is more realistic to prepare for hearing improvement without complete closure of the air-bone gap over the long term (>5 years). Immediate hearing results can often be excellent but can degrade over time ,27. It iCandidacy for aural atresia repair is based upon the ear-specific hearing assessment and CT findings. The most common scale used to describe the CT findings is the Jahrsdoerfer scale, a 10-point scale based upon the presence of 9 structures ,29. OtheIt is absolutely critical that surgeons considering atresia repair closely communicate with the surgeon who plans to manage the microtia reconstruction for a coordinated surgical timeline that optimizes outcomes while minimizing complications.Ear Prosthetic: atresia reconstruction surgery can be done at any time using an ear prosthetic, whether used with adhesive or surgically retained.Alloplastic Porous Polyethylene (PPE) reconstruction : atresia reconstruction surgery is ideally done before or at the time of microtia reconstruction (concurrent surgery). Canal surgery after alloplastic porous polyethylene implant risks damage to the flap vascularity, exposure, and extrusion of the implant with or without infection, which is poorly tolerated by alloplastic implants  or lower, while ears scoring seven or higher had an 89% chance ,29. Abse results . Other a results . Poorer  results .Average hearing gain from atresiaplasty is about 24 dB in appropriately selected patients, compared to 38 dB gain from osseointegrated implant-retained devices . AtresiaThere is concern for recurrent canal stenosis that occurs in up to one third of patients postoperatively . When thEar canal reconstruction may be necessary rather than optional when there is canal stenosis and concern for cholesteatoma. The presence of canal cholesteatoma may necessitate atresia repair prior to the normal sequence for optimal microtia reconstruction.Ultimately, an experienced atresia surgeon must candidly discuss the predicted hearing gain expected from surgery compared to the available implantable bone conduction hearing devices, as well as the option of fitting an ear-level air-conduction hearing aid in the reconstructed ear canal as a good means to further improve hearing.In discussing the spectrum of reconstructive options, observation should be presented with associated benefits and drawbacks. A select group of patients are satisfied and confident with the microtic ear, elect to wear their hair long and cover the ear, and/or prefer not to undertake the potential surgical and anesthetic risks.A realistic silicone ear prosthesis can be made for individuals of any age . ParentsSurgically placed osseointegrated implants can allow for a more secure attachment of the prosthetic by using a bar/clip, snap, or magnetic attachment, and can be implanted after the age of 5 years. The anaplastologist must be involved in the surgical planning as the location of the implant is paramount to a successful outcome of the prosthetic . Some paA successful prosthesis should fit well and be secure enough to use the entire day without worry . A prostOther considerations include the potential need to remove the prosthesis during contact sports and swimming. Care of the prosthetic ear includes removal at night before sleep and daily cleaning.Parents should be counseled that auricular prostheses and their replacement after normal wear and tear are generally covered by most insurances, though coverage varies. Ear prostheses provide the appearance of a normal outer ear with the psychological benefits of a symmetrical and realistic ear without the risk of surgery. The thought of a prosthesis inadvertently falling off may impact a child's self-image; this can be overcome with counseling and comparisons of the prosthetic ear to other commonly worn medical devices such as glasses and hearing aids.Alloplastic reconstruction, such as Medpor® and SuPor®, utilizes a high-density porous polyethylene implant covered with a well-vascularized fascial flap, typically the temporoparietal fascia flap (TPFF), which is then covered in remnant temporoparietal skin and skin graft . AlloplaThe most compelling advantages of alloplastic reconstruction are that the reconstruction is done in one stage, and the age at the time of surgery is not dependent on the child's growth and size, as is with cartilage reconstruction (see below).Disadvantages of alloplastic reconstruction include the overall risk of extrusion, fracture, and infection. Some feel this is amplified because the alloplastic reconstructed ear is insensate. Without sensation, the risk of injury, infection, and extrusion may be elevated and is lifelong. If extrusion does happen, the TPFF, often used for salvage in autogenous cartilage reconstruction, has already been exhausted in the initial repair. However, other fascial options such as the occipital artery flap may be utilized in salvage surgery. When the reconstructed ear's vascularity depends on a single vessel in a pedicled fascial flap, pressure may impact the viability. From the patient perspective, comfort with sleeping can be an issue that some children manage by sleeping with a special pillow around the ear to relieve the pressure.An alloplastic ear reconstruction performed at a younger age will be larger than the opposite ear to account for future ear growth; patients and family must be advised of and agreeable to this initial size discrepancy for younger children. The first Medpor ear was done in 1991. Beyond that time span, we do not have more longitudinal outcomes or long-term data of this reconstruction technique .Cases in which an alloplastic reconstruction may be most advantageous would be in instances of bilateral microtia, reducing the total number of surgeries and issues of symmetry, and for children who are extremely small for age (such as certain syndromic children), which otherwise would require the patient to wait for their teen years to have enough cartilage stock for adequate reconstruction. Also, for children with low hair lines, a technique that relies on coverage with TPFF is advantageous unless laser hair removal is pursued. Auricular reconstruction in older adults may be done with alloplastic reconstruction to eliminate the risk of having calcified cartilage stock which is difficult to carve.Use of a patient's own, or “autologous,” rib for auricular reconstruction is regarded by many as the gold standard for surgical microtia reconstruction . DecadesTanzer introduced the surgical techniques, which Brent subsequently refined to achieve acceptable autologous ear reconstruction results . VariatiAn advantage of cartilage reconstruction is the extensive knowledge base that has been amassed due to the broad use of this approach worldwide. The reconstructed ear has sensation and vascularity compared to an alloplastic ear. Cartilage reconstruction allows for the creation of an individualized ear, which is carved by the surgeon, to create symmetry with the opposite ear. This is ideal for various forms of microtia, particularly grades of microtia where part of the remnant ear can be saved, and part of the defect is reconstructed, such as in grade 2 microtia. Cartilage reconstruction allows the surgeon to reconstruct only the missing subunits of the ear, preserving part of the microtia ear as desired, which may not be possible with alloplastic techniques.Some argue that an older child of age 6–10 years can be more involved in the decision-making process, more invested in the surgery, and a more active participant in the care of the ear. In addition, the older child tends to have the opposite ear very close to adult size, allowing for a true size match of the reconstructed ear rather than an approximation based on projected growth. Others argue that later reconstruction in school-aged children can lead to poor self-image and self-concept, though the age that this occurs is controversial and likely different for every child .One disadvantage of cartilage techniques is the requirement for 2–4 stages, separated in time by 3–4 months, depending on the surgeon's technique. The earliest timing of surgery depends on the patient's chest size to allow for enough cartilage rib stock to create the ear, therefore necessitating a longer waiting period before surgery. There is also donor site morbidity at the time of surgery and a scar along the chest, though most patients do not report long-term adverse side effects for donor site issues. Patients do not have chest wall deformities or limitations in future activities or sports after rib cartilage harvest. Long term complications reported include framework resorption and wire extrusion, though overall, comparisons show less long-term complications using autologous cartilage compared to porous polyethylene . PneumotSeveral factors should be considered in the timing of cartilage-based reconstruction. The patient's age, size, and maturity are all critical factors.Age guidelines are general, as many factors such as genetics, diet, and medical comorbidities are strong determinants of a child's size. A chest circumference of 60 cm, measured at the xiphoid level has classically been the minimum indicator of the adequacy of rib stock. Classically, CT scans of the chest were performed to evaluate the costal cartilage, allowing for a view of the synchondrosis and evidence of calcification. However, with increasing awareness of radiation exposure in children with computerized tomography, this has been less practiced. More recently, ultrasound of the cartilage has been reported to accurately assess rib dimensions without the need for ionizing radiation exposure . MultidiTiming is critical when considering aural atresia repair in relation to auricular reconstruction. The desire of many families for aural atresia repair at a young age while deferring auricular reconstruction until a later time must be resisted if one wants to pursue autologous cartilage reconstruction. The local tissue changes resulting from atresia repair or a poorly placed osseointegrated implant can complicate or preclude successful cartilage reconstruction .Any technique, alloplastic or cartilage reconstruction, requires a high level of surgical expertise with an experienced surgeon to achieve reliable outcomes. Surgeons who perform microtia reconstruction should regularly perform the surgery and have advanced training.There are three primary techniques reviewed here, which are commonly used in variations customized by the reconstructive surgeon . Histori•1st stage: Costal cartilages 6–9 are harvested and carved. The cartilage framework is then placed deep to the retro and peri-auricular skin of the remnant.•2nd stage: The lobule of the microtia remnant is transposed to the framework.•3rd stage: The ear is elevated with the use of a skin graft placed in the posterior aspect of the ear and the advancement of the retroauricular skin.•4th stage: A tragus is created from contralateral conchal cartilage, and the conchal bowl of the construct is deepened.More recent variations on the Brent technique have reduced the number of stages to 3 by combining the tragus formation with the first stage, creating a tragus with the framework, and often combining the final stage with the placement of an osseointegrated hearing implant •12months-5 years: audiological testing and surveillance every 6–12 months•TM BAHA® SoundArc or Adhesive gel modes of Bone conduction sound processor use.5 years: Consider CT scan for hearing implants and canal reconstruction candidacy. Consider waiting for surgery to implant bone conduction device until after or in coordination with concurrent microtia reconstruction. Consider CochlearAge: Intervention recommended for microtia reconstruction•Newborn: Consultation with reconstructive surgeons for parental counseling regarding reconstructive options for the future•before or concurrently with alloplastic reconstruction3–5 years: Earliest age for consideration for alloplastic porous polyethylene reconstruction. Any ear canal surgery should be done •5 years: Earliest age for an osseointegrated anchor for prosthetic use. Prosthetics may be worn with adhesive prior to age 5.•after microtia reconstruction.5–9 years: Earliest age for autologous cartilage reconstruction. Any ear canal surgery is ideally done Caregivers of children born with microtia and atresia face numerous options for their hearing and reconstructive needs, the recommendations for which are often provided by separate and non-communicating disciplines. Plans for hearing augmentative devices, hearing reconstructive surgeries, and auricular reconstruction should be provided in a cohesive manner, with close communication between the atresia repair/hearing rehabilitation surgeon and the microtia reconstruction surgeon. This guideline aims to integrate the hearing and reconstructive recommendations with a timeline that allows for the understanding of all options available, realizing that every patient is unique and requires an individualized plan.


Given the high prevalence of presbycusis and the damage it brings about, a screening test can be useful in the identification of hearing loss in primary care.Aim: To estimate the prevalence of hearing loss in a representative sample of elderly people living at Butantan using an audiological screening method (questionnaire) and a basic audiological evaluation; to compare the results of the two kinds of evaluations, checking the validity of this tool for hearing loss screening.Design: Cross sectional descriptive study.Materials and Methods: 200 individuals  were randomly selected to undergo audiological screening (questionnaire). Another randomly selected group encompassed 100 individuals who were submitted to a set of audiological tests. Then, we compared the results from the two methods.Results: There were no statistically significant associations between the questionnaire and the degree of hearing loss of the patients.Conclusion: The prevalence of hearing loss in our sample was of 56% in the screening and of 95% when checked by the audiological evaluation. Therefore, screening was not proven valid to assess hearing when compared to audiological evaluation. Today, Brazil is going through a period of growth of its elderly population. According IBGE projections for 2028, we are expected to have 38 million people with more than 60 years of ageThis populational growth will bring about an even greater demand for public health policies, especially in terms of diagnosis and treatmentOne of the implications of this boom in this population will be a likely increase in presbycusis, which is an aging-related type hearing loss. Its etiology may have consequences which stem from a number of insults inflicted throughout one's life, including aging-related degeneration, noise exposure, ototoxic agents and otological agents, in general. Presbycusis can be considered whenever, in the absence of other etiologies, there is bilateral, symmetrical, insidious hearing loss, especially in the high frequencies, however it can affect all hearing frequencies, in a population older than 40 years. It is highly influenced by genetics, diet and systemic diseases, and it may affect 30 to 60% of the geriatric population, and prevalence will be greater or lower in relation to socioeconomic variablesHearing loss acquired during adulthood can impair quality of life and the person's integration to society. Because of the hearing loss, many individuals change their life structures, bringing about professional and affection losses, and it may also negatively impact relationships with friends and familiesThe psychological impact stemming from the hearing loss can be assessed by means of self-assessment questionnaires, which are useful tools used to quantify the emotional and social consequences perceived in function of the hearing loss. These instruments may be used in different clinical routines, such as screening and/or initial interviews, assessment of the sound amplification device and assessment of the auditory rehabilitation programs, providing the audiologist the means to understand the impact of this handicap in the elderly and the needs of this populationBecause of the high prevalence of presbycusis and the handicap it causes, a screening may be useful to identify the hearing loss in primary care. Although its importance is clear, especially in developing countries, the screening methods vary considerably in terms of strategies, techniques, application and effectiveness. Audiometry is the gold standard test to assess hearing loss; nonetheless, it can be difficult in some places because of problems associated with access, reference and reimbursement. For these reasons, many clinicians rely on self-deployed questionnaires as means to screen for hearing loss, since they are fast and inexpensive instruments1)To estimate the hearing loss prevalence in the elderly who live in the Health District of Butantã using the audiological screening and basic audiologic evaluation;2)To compare the audiological screening results and that of basic audiological evaluation, checking the validity of such instrument to be used as hearing screening tool.Thus, the goals of the present study were:The study was carried out within the standards required by the Declaration of Helsinki and it was approved by the Ethics in Research Committee of our Institution (#1024). This institution is a reference hospital for those individuals who live in the geographic area covered by the Health District of Butantã, with an estimated population of about 400,000 people.We carried out a cross-sectional cohort study, using the sample defined for the study: “A epidemiologia da demência e doença de Alzheimer em populações miscigenadas no Brasil e em Cuba”, also carried out by this institution.-Censused sectors which have slums, such as São Remo, São Domingos, Sapé, Vila Dalva and others. The Jardim São Remo slum started in an area which belonged to the University of São Paulo about 30 years ago. It has a relatively stable population, with well-defined streets and houses with numbers, it has been counted in recent censuses and they have electrical power and running water. The remaining is more recent and some are in risky areas. Besides socio-economic deprivations, the residents of these slums have high likelihood of having little or no formal education at all. They are mostly domestic migrants, who lived the beginning of their lives in poor areas of the country;-Censured sectors of residential areas from the districts of Butantã, Rio Pequeno and Raposo Tavares, defined at random according to socio-economic metrics. The collection areas were numbered by household in order to register the residents with 65 years of age or more. All the co-residents of elderly patients were also identified. All the residents with more than 60 years of age from the selected censused sectors were recruited. The total number of participants was 2,000. Those individuals aged 60 years or more were considered elderly, based on the criterion established by the World Health Organization, which establishes this age range as the beginning of the elderly age in developed countries.For sample selection purposes, we selected the areas covered by the hospital - those belonging to the administrative districts of Butantã, Rio Pequeno and Raposo Tavares, broken down into two groups:We randomly selected 200 individuals from both genders, at the age range starting from 60 years, among all the participants in the study: “A epidemiologia da demência e doença de Alzheimer em populações miscigenadas no Brasil e em Cuba”.Of the 200 initially selected individuals, fifteen could not take part in the study. The causes for not participating were: cognitive deficit which prevented them from understanding the questions (7 cases); refusal to answer the questionnaire (4 cases); impossibility of applying the entire questionnaire because of lack of contact with family member and/or caretakers, which should answer the last question (4 cases). Thus, the series was formed by 185 individuals who underwent the screening.For the second stage of the present study, we selected again 100 from the 200 previously selected individuals, half from each gender. Of these 100, 10 previously selected individuals could not undergo complete audiological evaluation. The causes were: unanswered questionnaire (2 cases); the individual did not feel well during the test (3 cases) and did not understand the orders given during the assessment (4 cases). Thus, in this stage, 91 individuals participated.Only those individuals who agreed with participated in the study, and they signed the free and informed consent form .screening) with 15 questions, concerning the different day-today communication situations and hearing difficulties, as well as social isolation, which aimed at assessing the impact caused by the hearing loss to the elderly's life. This questionnaire is used in the hospital's audiology department, and it was created based on the Nursing Home Hearing Handicap - NHHIHearing Handicap Inventory for the ElderlyHearing Handicap Inventory for Adults - HHIAWe then applied a questionnaire ;-Group 2: 11 to 20 points (mild/moderate handicap perception);-Group 3: 21 to 45 points (severe/significant handicap perception).The questions were answered by the elderly himself and only one question was asked to family members (the family member's impression on the elderly's hearing difficulties). The answers from each questionnaire were added up and we then we obtained the final score for each individual. Based on this result, the individuals were broken down into three groups. For each group we associated a handicap perception based on the performance analysis criterion of the individuals assessed by the screening process according to:During audiological evaluation, we initially studied the hearing thresholds obtained for frequencies 250 to 8,000 Hz through air conduction and, when these thresholds went beyond 20 dB HL, they were also determined by bone conduction in the frequencies of 500 to 4,000 Hz. The hearing thresholds were classified in degrees, according with the Lloyd and KaplanFollowing that, we studied the speech detection threshold and we obtained the speech intelligibility curve. For these procedures we used the Madsen audiometer - model Midimate 622.We also did tympanometry and ipsi and contralateral acoustic reflex studies, using the GSI middle ear analyzer - Tympstar model.We used the chi-square tests for Independence and Anova, as well as the confidence interval approach. The significance level assigned was of 0.05 (5%).-Group 1 - 107 individuals (57.8%);-Group 2 - 43 individuals (23.2%);-Group 3 - 35 individuals (19%).For the 185 individuals who answered the questionnaire (auditory screening), the groups were broken down according to the score obtained:-Group 1 - 40 individuals (43.95%);-Group 2 - 29 individuals (31.85%);-Group 3 - 22 individuals (24%).For the 91 individuals who also underwent audiologic assessment, the groups were broken down according to the score obtained in the questionnaire, and they were distributed as follows:For the audiological evaluation analysis, we considered the degree of hearing loss according to the worst threshold presented and the results were presented and broken down by groups, according to the result from the questionnaire, for the 91 individuals who participated in this stage of the evaluation. The results are described on Through the results obtained from the audiological evaluation we can notice that in the three groups, most of the individuals had moderate hearing loss. The second largest occurrence in group 1 was the mild hearing loss and in groups 2 and 3 it was the severe hearing loss.We can also notice that only 10 of the 182 ears did not have any degree of hearing loss, in other words, 5.5% of the ears.As to the type of hearing loss, there were no cases of conductive hearing loss and only 4 cases of mixed hearing loss. The other hearing loss cases were of the sensorineural type (93.4%).p = 0.085).Based on the results presented on handicap (degree 3), the likelihood of the person having hearing loss was of 100%.Based on We carried out a new comparison, associating the mean value of the score obtained from the questionnaires and the hearing thresholds. To do that, the individuals were grouped according to hearing thresholds in the worst ear, in other words, Group A , Group B (mild hearing loss), Group C (moderate hearing loss) and Group D (moderately severe to profound hearing loss). The results are depicted on In regards of the perception of the handicap, checked in the questionnaire, we noticed that the majority of individuals studied (approximately 56%) reported they perceived it, which is in agreement with those findings from Pinzan-Faria and IórioThe prevalence of hearing loss, studied by the basic audiological evaluation in this study was very high, in other words, around 95%, which is different from similar studies, in which the prevalence was around 60 to 70%In regards of the audiological profile of the population studied, we noticed the prevalence of bilateral sensorineural hearing loss, of descending shape. Such findings have also been reported by Melo et al.As to the degree of hearing loss, we noticed a predominance of moderate hearing loss, and the mild hearing loss type was the second largest occurrence in Group 1; severe hearing loss was the second highest occurrence in Groups 2 and 3. These results differ from those of other similar studies, since most report a higher prevalence of mild hearing lossIn the analysis which compared the complaint stated in the questionnaire and the degree of hearing loss, there was no statistically significant association for the right and left ears. These data indicate that the individual with a hearing handicap may not show hearing loss necessarily, or not have such a severe hearing loss as stated in the questionnaire. The opposite is also possible, in other words, individuals who do not complain of hearing loss in the questionnaire, have hearing loss of different degrees. These observations were also made by other authorsIn order to check whether the questionnaire used was sensitive as an only method for auditory screening, we compared the likelihood of hearing loss with the degrees obtained through the handicap quantification done by the questionnaire. This analysis revealed a very high number of false-negative results, considering those patients who did not perceive a handicap (degree 1). If we consider only the elderly who had degrees 2 and 3 of hearing loss as per reported in the questionnaire, the instrument's sensitivity proved to be higher than 96%. Nonetheless, in this study, as per previously mentioned, there was a very small number of individuals without hearing loss, and this has impaired more specific conclusions on this aspect. Notwithstanding, this instrument alone was not feasible for hearing screening because of a large number of false-positive, which matches the findings from Pinzan-Faria and IórioAnd finally, the last analysis made tried to study whether a worsening in auditory thresholds had any relation with the mean score obtained in the questionnaire. This relation proved positive, in other words, as the elderly got worse in their auditory sensitiveness, there was an increase in their self-perception of the handicap, proven by a worsening in the questionnaire scores, per group, and this was also reported by Pinzan-Faria and IórioThe growth in the number of elderly people in the population will increase even further the demand for public health policies, especially in regards of presbycusis. Thus, it is urgent to establish the guidelines to develop diagnostic programs, individual sound amplification devices and a specific program of auditory reeducation for the elderly with hearing loss, so as to prevent them from suffering the psychological and social losses stemming from the hearing impairmentThe present study reported that the questionnaire utilized is not a method to be used alone in auditory screening; however, it indicates the degree of hearing loss for the elderly, which is highly variable, regardless of the hearing loss level, since it depends on social and psychological adaptation factors, as well as on factors associated with age and physical healthscreening and 95% according to basic audiological evaluation.1) The hearing loss prevalence found in this population was approximately 56% according to the screening (questionnaire) did not prove to be a valid instrument to be used in auditory screening, when compared to basic audiological evaluation.2) The


ObjectiveThe objective of this study is to assess the relationship between the site of tympanic membrane (TM) perforation and the type and degree of hearing impairment. The secondary objective was to compare the duration of the disease and the degree of hearing loss.Study designThis is a prospective observational study.Place and duration of the studyThis study was carried out in the Department of Otolaryngology/Head and Neck Surgery at the Pakistan Institute of Medical Sciences, Islamabad, from May 2021 to April 2022.Patients and methodsOf all the screened patients, 77 fulfilled the inclusion criteria. Patients aged 10-40 years with inactive mucosal chronic otitis media and unilateral perforation in one quadrant were included. The site of TM rupture was observed, and audiometric analysis was performed.ResultsThe mean age of participants was 25 ± 8.61 years, with a preponderance of the female gender (57.1%). A total of 32 (41.6%), 19 (24.7%), 19 (24.7%), and seven (9.1%) perforations involved posterosuperior, anterosuperior, anteroinferior, and posteroinferior quadrants respectively. Conductive, mixed, and sensorineural hearing loss was found in 52 (67.5%), 18 (23.4%), and seven (9.1%) cases, respectively. Of all the subjects, 13 (16.9%) had the disease for < one year, 39 (50.6%) for one to five years, 17 (22.1%) for five to 10 years, and eight (10.4%) for > 10 years. There was a statistically significant association between the degree of hearing loss and the site of perforation. No significant association was found between the site of perforation and the type of hearing loss. Duration of disease and degree of hearing loss also had no significant association.ConclusionThe extent of hearing loss was found to be directly influenced by the anatomical site of perforation, with the posterosuperior quadrant perforation producing the greatest degree of impairment. Chronic suppurative otitis media (CSOM) is one of the most frequently encountered diseases in ENT practice. It primarily affects children and has remained one of the commonest infectious diseases in the pediatric age group worldwide . The sitDifferent studies have shown that CSOM is likely to cause at least a mild to moderate degree of hearing loss in the majority of cases due to its direct effect on air conduction. Factors that affect the degree and type of hearing loss include size, site, and perhaps morphology of TM perforation. In addition, the involvement of the middle ear and its ossicles can independently affect the sound conduction mechanism . RecurreA correlation between the site of perforation, type of hearing loss, duration of disease, and degree of hearing loss would help otorhinolaryngologists to adequately determine the treatment of choice. In addition, it should help in a better management plan, thus minimizing the complications of CSOM and providing patients with a better quality of life.The Department of Otorhinolaryngology and Head/Neck Surgery of Pakistan Institute of Medical Sciences (PIMS) Islamabad, a tertiary health care hospital, was the designated site for this study. The institute is categorized as a tertiary care hospital in Islamabad, Pakistan. The institute-associated ethical clearance committee granted formal permission to conduct the study (Ref no.: F.1-1/2015/ERB/SZABMU/539). This prospective observational study was conducted over the course of a year, from May 2021 to April 2022.The study sample size consisted of 324 patients. Inclusion criteria dictated that patients aged 10 to 40 years were clinically identified as having a quiescent mucosal type of chronic otitis media in the unilateral ear while simultaneously having unimpaired hearing and clinical normalcy in the opposite ear. The research excluded patients with bilateral CSOM, multiple perforations, and a large perforation involving more than one quadrant. Exclusion rendered the patient population to a total of 77. Patients with age-induced hearing loss, accidental damage, and those on previous ototoxic regimens were ruled out for audiometric analysis since hearing loss in these cases was unrelated to CSOM. The criteria were set to include patients who would be compliant in the examination process and, at the same time, exclude those in whom comorbidities may have an independent effect on hearing loss.A thorough history and demographic data were obtained using a predesigned proforma. A full-size otoscope and a microscope-assisted ear exam were performed on each patient. The orientation of the handle of the malleus was used to identify the side of the ear and the site of the TM perforation. The rest of the anatomical features was also thoroughly examined.An audiometer, Primus Pro , calibrated in accordance with ISO standards, was used in a buffered room, where the audiometric analysis was carried out on patients. Reference frequencies chosen for this study were 250-8000 Hz. When applicable, masking methods were used to estimate the air and bone conduction threshold. Air conduction limits at 500, 1000, 2000, and 4000 Hz were reflective of the hearing level, and the mean calculation of these frequencies was used to assess the hearing. The air-bone gap (ABG) was also measured. An ABG ≥ 20 dB was interpreted as conductive hearing loss, whereas ≤20 dB meant sensorineural hearing loss. The mixed hearing loss meant an ABG ≥ 20 dB, along with a noticeable impairment of bone conduction. WHO grading system  was usedThe data were entered and analyzed statistically using the Statistical Package for Social Services v23  for Windows. Frequencies, percentages, mean values, and ranges were calculated where required. The Chi-square test was used for comparison; a p-value < 0.05 was considered a statistical significance.Only 77 patients out of a total of 324 examined fulfilled the criteria for inclusion in the study. Age of participants ranged from 11 to 38 years. The ages of the patients involved are tabulated in Table Of the total participants, 33 (42.9%) were male, and 44 (57.1%) were female. As patients with unilateral perforation in a single quadrant were included, 41 (53.2%) patients had a perforation in the right ear, while 36 (46.8%) had a perforation in the left ear.Regarding the site of TM perforation, out of a total of 77 patients included in the study, the posterosuperior quadrant was the most frequently involved at a frequency of 32 41.6%). Anterosuperior and anteroinferior quadrants had 19 (24.7%) perforations each, while posteroinferior perforation was found in seven (9.1%) cases. Figure .6%. AnteThe conductive type of hearing loss was found in 52 (67.5%) of the cases, sensorineural hearing loss was found in seven (9.1%), and mixed hearing loss was found in 18 (23.4%) of cases. In 13 (16.9%) patients, the disease was less than a year old; in 39 (50.6%) cases, the disease was between one and five years old. The disease was between five and 10 years old in 17 (22.1%) cases and more than 10 years old in eight (10.4%) cases.Different characteristics of TM perforation were also compared with the degree and type of hearing loss. Out of a total of 19 24.67%) patients with anterosuperior perforation, six (31.6%) had mild, moderate, and moderately severe hearing loss each, while one (5.2%) had profound hearing loss. Similarly, out of a total of 19 patients with anteroinferior perforation, four (21.1%) had mild, 14 (73.7%) had moderate, and one (5.2%) had severe degree of hearing loss. Patients found to have posterosuperior perforation were 32 (41.55%) in number, with 10 (31.2%) having mild, 13 (40.6%) having moderate, four (12.5%) each having moderately severe and severe, and one (3.2%) having a profound degree of hearing loss. Patients with posterosuperior perforation were seven (9.09%) in number, with four (57.2%) having mild, two (28.6%) having moderate, and one (14.3%) having a profound degree of hearing loss. This is presented in tabulated form in Table 4.67% patWhen the site of perforation was compared with the degree of hearing loss, it was found that there was a statistically significant association between the two, with the posterosuperior quadrant perforation producing the greatest degree of impairment (p = 0.042).Type of hearing loss was also compared with the site of perforation, and it was found that 11 (57.9%) anterosuperior perforations had conductive hearing loss (CHL), three (15.8%) had SNHL, and five 26.3%) had mixed hearing loss. Regarding anteroinferior perforation, it was found that 13 (68.4%) had CHL, two (10.5%) had SNHL, and four (21.1%) had mixed hearing loss. Patients with posterosuperior perforation had CHL in 22 (68.7%) patients, two (6.2%) had SNHL, and eight (25.1%) had mixed types of hearing loss. Posteroinferior perforations had six (85.7%) cases with CHL and one (14.3%) with mixed hearing loss. Details of these findings are summarized in Table % had mixWhen the disease duration was correlated with the degree of hearing loss, no statistically significant association was found between the two p = 0.294). The data compiled is presented in Table . The datThis study revisited some old as well as a few new aspects in relation to hearing loss associated with TM perforation. Ediale et al.  includedIn this study, we followed a similar pattern as Aslıer et al. , who excMaharjan et al.  and NepaCastelhano et al.  establisRegarding a link between the severity of hearing loss and the duration of the TM perforation, relatively less published literature is present. Pannu et al.  in theirAnother aspect of CSOM that deserves mention is its negative effect on the quality of life (QoL). Various studies have shown a statistically significant improvement in hearing threshold and overall QoL in vastly different patient groups  who had undergone corrective surgery, especially tympanoplasty, for TM perforation -35.Limitations of our study include relying on patients' history for recording the duration of disease, relying on a single examination to confirm a quiescent type of disease, and relying on a clinical examination instead of photographic evidence by the use of a video otoscope, which is always preferable for future reference and confirmation of signs.Strengths of this study include a relatively large sample size based on the inclusion and exclusion criteria and assessment of the association between many different aspects of hearing loss associated with tympanic membrane perforation, which has usually been done separately in the literature, that too on different population groups with little connection to each other.Our research has led us to conclude that the location of the perforation affects the extent of hearing impairment experienced by the patient, with the perforation in the posterior superior quadrant causing the most significant impairment. In addition, conductive hearing loss was the most frequent type of hearing loss encountered in these cases. However, it was also noted that the site of perforation plays no significant role in determining the type of hearing loss, with most subjects having mild to moderate hearing loss. In addition, when hearing loss and disease duration were compared, it was discovered that an extended course of illness had no discernible impact on the severity of hearing loss.