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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: UNLABELLED, METHODS, RESULTS. Meshes: Adult, Artifacts, Brain, Epilepsy, Female, Flumazenil, Humans, Image Enhancement, Imaging, Three-Dimensional, Iodine Radioisotopes, Magnetic Resonance Imaging, Male, Reproducibility of Results, Sensitivity and Specificity, Tomography, Emission-Computed, Single-Photon.
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Does mRI-based correction for partial-volume effect improve detectability of intractable epileptogenic foci on 123I-iomazenil brain SPECT images? Context: (123)I-Iomazenil brain SPECT has been used for the detection of epileptogenic foci, especially when surgical intervention is considered. Although epileptogenic foci exhibit a decrease in (123)I-iomazenil accumulation, normal cerebral cortices often exhibit similar findings because of thin cortical ribbons, gray matter atrophy, or pathologic brain structures. In the present study, we created (123)I-iomazenil SPECT images corrected for gray matter volume using MRI and tested whether the detectability of the epileptogenic foci improved. Seven patients (1 male patient and 6 female patients; mean age +/- SD, 34 +/- 17 y) with intractable epilepsy were surgically treated by resecting the cerebral cortex after surface electroencephalography. Histopathologic examination of the resected specimens and a good outcome after surgery indicated that the resected lesions were epileptogenic foci. These patients underwent (123)I-iomazenil SPECT and 3-dimensional T1-weighted MRI examinations before their operations. Each SPECT image was coregistered to the corresponding MR image, and its partial-volume effect (PVE) was corrected on a voxel-by-voxel basis with a smoothed gray matter distribution image. Four nuclear medicine physicians visually evaluated the (123)I-iomazenil SPECT images with and without the PVE correction. The SPECT count ratio of the suspected focus to the contralateral cerebral cortex was evaluated as an asymmetry index (%) based on the volume of interest. The sensitivity, specificity, and accuracy of focus detection by visual assessment were higher after PVE correction (88%, 99%, and 98%, respectively) than before correction (50%, 92%, and 87%, respectively). The mean asymmetry index for the surgically resected lesions was significantly higher on the PVE-corrected SPECT images (22%) than on the PVE-uncorrected ones (16%) (P = 0.006).
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MRI-based PVE correction for (123)I-iomazenil brain SPECT improves the sensitivity and specificity of the detection of cortical epileptogenic foci in patients with intractable epilepsy. Final Decision: yes