[Anatomo-functional study in branch retinal vein occlusion using Swept Source Optical Coherence Tomography Angiography]. / Occlusion de branche veineuse rétinienne : analyse anatomo-fonctionnelle par Swept Source Optical Coherence Tomography Angiographie (OCT-Angiographie).

INTRODUCTION: The purpose of our study was to describe the microvascular abnormalities on OCT-angiography in eyes with branch retinal vein occlusion (BRVO), to measure the surface of the foveal avascular zone (FAZ) and the capillary density, and to establish anatomic-functional correlations. METHODS: We conducted an observational prospective study in the ophthalmology department of Habib Thameur Hospital in Tunis, which included 17 eyes of patients with unilateral BRVO. We studied the microvascular abnormalities and areas of capillary non-perfusion in the deep and superficial capillary plexuses (DCP, SCP). The area of the FAZ was measured in the SCP and correlated to visual acuity. The foveal and parafoveal capillary density was measured with flow quantification software. RESULTS: The mean patient age was 57.94 ±18.04 years. Male:female ratio was approximately 1. Fourteen eyes (82.4%) showed cystoid macular edema which was significantly correlated to poor visual acuity (P=0.02). Vascular congestion was present in 12 eyes (70.60%) in the DCP and 8 eyes (47.1%) in the SCP. Intraretinal loops were found in 5 eyes (29.4%) in the DCP and 8 eyes (47.1%) in the SCP. Thirteen eyes (76.5%) exhibited vascular tortuosity in the DCP, and 14 eyes (82.4%) in the SCP. Areas of capillary non-perfusion were observed in 12 eyes (70.60%). The mean area of the FAZ was 617.53±525.75µ in eyes with BRVO. Enlargement of the FAZ was correlated to visual loss (P=0.01). Mean foveal capillary density was 15.49% (±5.18%), and mean peripheral capillary density was 44% (±4.75%). There was no correlation between vascular density and visual acuity in our series. CONCLUSIONS: OCT-angiography is part of the current diagnostic workup for RVO. It has a relevant role in establishing a prognosis by studying the area of the FAZ and the capillary density.

[Role of SD-OCT in the diagnosis and prognosis of macular hypoplasia in nystagmus patients]. / Apport de l'OCT-SD maculaire dans le diagnostic et le pronostic de l'hypoplasie fovéolaire chez les patients ayant un nystagmus.

PURPOSE: To investigate whether spectral domain optical coherence tomography (SD-OCT) is helpful for the diagnosis and prognosis of foveal hypoplasia in patients with overt nystagmus. METHODS: A retrospective cross-sectional study was conducted in 48 patients with overt nystagmus. All patients underwent a complete ophthalmic examination including best corrected visual acuity, biomicroscopic and fundus examinations. Spectral domain optical coherence tomography was performed using 3D OCT-2000 FA PLUS Topcon, Tokyo, Japan, for the diagnosis and grading of foveal hypoplasia, using the Thomas classification, and its possible correlation with visual acuity. RESULTS: Foveal hypoplasia was diagnosed in 6 patients (12.5%). The mean age of the patients was 13.2 years (10-18 years). Mean visual acuity was 1.53/10 (0.87 LogMAR). Foveal hypoplasia was associated with aniridia in 2 patients, albinism in 3 patients and keratoconus in 1 case. On SD-OCT, foveal hypoplasia was grade 4 in 4 patients and grade 3 in 2 patients. Mean visual acuity was 2.55/10 in patients with grade 3 foveal hypoplasia and 1.22/10 in patients with grade 4 foveal hypoplasia, and the difference in visual acuity between the two groups was statistically significant (P<0.001). CONCLUSION: SD-OCT plays a double role in the diagnosis and prognosis of foveal hypoplasia in patients with nystagmus.