Assessment of the spectralis spectral domain oct segmentation software in a retrospective cohort study of exudative amd patients

Purpose To assess the ability of the Spectralis optical coherence tomography (OCT) segmentation software to identify the inner limiting membrane and the Bruch’s membrane in exudative AMD patients. Methods Thirty-eight eyes of 38 naive exudative AMD patients were retrospectively included. They all had a complete ophthalmologic examination including Spectralis OCT at baseline, at month-1 and at month-2. Reliability of the segmentation software was was defined as good if both inner limiting membrane and Bruch’s membrane were correctly drawn. Results A total of 38 patients charts were reviewed (114 scans). The inner limiting membrane was correctly drawn in 114/114 SD-OCT scans (100 %). Conversely, the Bruch’s membrane was correctly drawn in 59/114 scans (51.8 %). The software was less reliable in locating the Bruch’s membrane in case of pigment epithelium detachment (PED) than without PED (42.5% vs 73.5 % respectively, p =0.049). Conclusion Segmentation of inner limiting membrane was constantly trustworthy but Bruch’s membrane segmentation was poorly reliable using the automatic SD-OCT Spectralis segmentation software. Based on this software, evaluation of retinal thickness may be incorrect, particularly in case of PED. • 2612 High-resolution spectral domain optical coherence tomography findings in reticular pattern dystrohy ZERBIB J 1, MASSAMBA N 1, QUERQUES G 1, 2, BLANCOGARAVITO R 1, SROUR M 1, BONNET C 1, SOUIED EH 1 (1) Ophthalmology, Creteil (2) Ophthalmology, Milano Purpose To analyze specific outer retinal and retinal pigment epithelium (RPE) features in reticular pattern dystrophy using spectral-domain optical coherence tomography (SD-OCT). Methods Consecutive patients with reticular pattern dystrophy underwent a complete ophthalmologic examination, including assessment of best-corrected visual acuity (BCVA), fundus biomicroscopy, and SD-OCT (Spectralis SD-OCT, Heidelberg Engineering). Outer retinal and RPE macular features, as evaluated by SD-OCT (scan passing through the fovea) were analyzed by 3 authors (JZ, NM and GQ). Results 24 eyes of 13 patients (5 males, 8 women, mean age 71.4) were included. Mean visual acuity was measured at 0.30 (logMAR). The RPE layer in the foveal area appeared normal in 41.7% of scans, while small RPE elevations and RPE bumps were detected in 33.3% and 20.8% of scans, respectively. Inner segment/outer segment (IS/OS) junction appeared disrupted in 50% of scans, and absent in 58.3% of scans. SD-OCT showed a slight IS/OS elevation in 54.2% of scans. The external limiting membrane (ELM), appeared disrupted in 50% of scans, absent in 37.5% of scans, and elevated in 66.7% of scans. Hypereflective subretinal material accumulation or hyporeflective subretinal lesions, were detected in 33.3% and in 12.5% of scans, respectively. SD-OCT showed hyporeflective retinal pseudocysts in 16.7% of scans. Conclusion In this series of reticular pattern dystrophy, SD-OCT showed disruption of RPE layer and RPE bumps. Outer retinal changes included absence and disruption of both IS/OS junction and ELM. Hypereflective subretinal material accumulation or hyporeflective subretinal lesions, and hyporeflective retinal pseudocysts were also noticed. • 2614 Natural evolution of idiopathic lamellar macular holes (LMH) and macular pseudoholes (MPH) GARCIA FERNÁNDEZ M, CASTRO NAVARRO J Ophthalmology, HUCA, Oviedo Purpose To analyze the natural evolution of idiopathic Lamellar Macular Holes (LMH) and Macular Pseudoholes (MPH), in the long-term, based on Optical Coherence Tomography (OCT) configuration and in Best Corrected Visual Acuity (BCVA) evolution. Methods We prospectively analyzed 68 eyes (41 right eyes and 27 left eyes) of 61 patients (40 female and 21 male), which were diagnosed as having a MPH or a LMH on OCT examination. The following variables were assessed: BCVA, lens status, and hole size (Diameter -D, Residual foveal Thickness –RT, and Perifoveal Thickness -PT)(software Caliper of Cirrus OCT), at baseline and final examination. Eyes with significant cataract underwent phacoemulsification. Results The mean follow-up period was 34.33 ± 15.02 (12-78) months. Mean BCVA (logMAR notation) in the total group at baseline was 0.40 ± 0.25 and at final was 0.36 ± 0.13 (p=0,082). PAM showed slightly better BCVA than LMH (p<0.05). BCVA improved in those eyes who underwent cataract surgery and remained unchanged in the rest of the eyes.No statistically significant differences regarding D, RT and PT were observed during the follow-up period (p=0,125). Conclusion Most of idiopathic LMH and MPH do not progress anatomically and do not contribute to a significant diminution of visual acuity during the follow-up period. We must take into account that the diminishment in visual acuity in most LMH and MPH can be due to the presence of an opacified crystalline and not to the lamellar hole itself.