Investigating Tissue Optical Properties and Texture Descriptors of the Retina in Patients with Multiple Sclerosis

PURPOSE: To assess the differences in texture descriptors and optical properties of retinal tissue layers in patients with multiple sclerosis (MS) and to evaluate their usefulness in the detection of neurodegenerative changes using optical coherence tomography (OCT) image segmentation. PATIENTS AND METHODS: 38 patients with MS were examined using Stratus OCT. The raw macular OCT data were exported and processed using OCTRIMA software. The enrolled eyes were divided into two groups, based on the presence of optic neuritis (ON) in the history (MSON+ group, n = 36 and MSON- group, n = 31). Data of 29 eyes of 24 healthy subjects (H) were used as controls. A total of seven intraretinal layers were segmented and thickness as well as optical parameters such as contrast, fractal dimension, layer index and total reflectance were measured. Mixed-model ANOVA analysis was used for statistical comparisons. RESULTS: Significant thinning of the retinal nerve fiber layer (RNFL), ganglion cell/inner plexiform layer complex (GCL+IPL) and ganglion cell complex (GCC, RNFL+GCL+IPL) was observed between study groups in all comparisons. Significant difference was found in contrast in the RNFL, GCL+IPL, GCC, inner nuclear layer (INL) and outer plexiform layer when comparing MSON+ to the other groups. Higher fractal dimension values were observed in GCL+IPL and INL layers when comparing H vs. MSON+ groups. A significant difference was found in layer index in the RNFL, GCL+IPL and GCC layers in all comparisons. A significant difference was observed in total reflectance in the RNFL, GCL+IPL and GCC layers between the three examination groups. CONCLUSION: Texture and optical properties of the retinal tissue undergo pronounced changes in MS even without optic neuritis. Our results may help to further improve the diagnostic efficacy of OCT in MS and neurodegeneration

Accuracy of Matching Optic Discs with Visual Fields: The European Structure and Function Assessment Trial (ESAFAT).

PURPOSE: To determine the ability of ophthalmologists across Europe to match stereoscopic optic disc photographs to visual fields of varying severity. DESIGN: Evaluation and comparison of 2 diagnostic tests. PARTICIPANTS: A total of 109 of 260 invited ophthalmologists in 11 European countries. These had participated in the previous European Optic Disc Assessment Trial (EODAT), a trial on glaucoma diagnostic accuracy based on optic discs only. METHODS: Each participant matched stereo optic disc photographs of 40 healthy and 48 glaucomatous eyes to a visual field chosen from 4 options per disc. The 4 presented visual fields included the corresponding one and 3 other visual fields, varying in severity. The matching accuracy and any inaccuracy per disease severity were calculated. Classification accuracy (as glaucomatous or healthy) was compared with EODAT data. Duplicate slides allowed for the assessment of intraobserver agreement. MAIN OUTCOME MEASURES: Accuracy of matching optic discs with their corresponding visual field and of classifying them as healthy or glaucomatous; intraobserver agreement (\u3ba). RESULTS: The overall accuracy of ophthalmologists for correctly matching stereoscopic optic disc photographs to their visual fields was 58.7%. When incorrectly matched, the observers generally overestimated the visual field severity (P\u2009<\u20090.001), notably in eyes with early glaucoma. The intraobserver agreement was, on average, moderate (0.52). CONCLUSIONS: European ophthalmologists correctly matched stereoscopic optic disc photographs to their corresponding visual field in only approximately 59% of cases. In most mismatches, the clinicians overestimated the visual field damage