Comparison of anterior segment parameter values obtained with Scheimpflug-Placido topographer, optical low coherence reflectometry and noncontact specular microscopy in morbid obesity.
To investigate the measurement of anterior segment parameters using Sirius Scheimpflug-Placido topographer, Lenstar optical low coherence reflectometry (OLCR), and noncontact specular microscopy (SM) in morbidly obese and nonobese subjects. Twenty-eight morbidly obese subjects (BMI ≥ 40; Group 1) and 28 age- sex-matched healthy nonobese subjects (BMI 18.50-24.99; Group 2) were included in this study. Anterior segment parameters were measured by Scheimpflug-Placido topographer and OLCR. Corneal endothelial cell parameters were measured by non-contact SM. The group data were analyzed using the Mann-Whitney U test and Student's t-test. Bland-Altman plots were used to assess agreement among the instruments, and 95% limits of agreement (LoA) for each comparison were calculated. In group 1, the mean CCT by Scheimpflug-Placido topographer, OLCR, and noncontact SM were 549.44±30.10 µm, 544.15±31.48 µm, and 541.59±29.87 µm respectively. In group 2, the mean CCT by Scheimpflug-Placido topographer, OLCR, and noncontact SM were 531.0±22.09 µm, 523.15±21.39 µm, and 521.12±21.70 µm respectively. Mean CCT values obtained by the three methods were significantly higher in the morbidly obese than the nonobese subjects. In both groups, mean CCT was significantly higher when measured by Scheimpflug-Placido topographer than by OLCR and noncontact SM, and mean AD and ACD were significantly higher when measured by Scheimpflug-Placido topographer than OLCR. No significant differences were found between mean corneal curvature and corneal astigmatism when measured by Scheimpflug-Placido topographer and OLCR. The mean CCT of the morbidly obese subjects were significantly higher than the nonobese subjects when measured by all three methods. The CCT values obtained by Scheimpflug-Placido topographer were significantly higher than those by OLCR and SM.