A. Hassairi

Optical coherence tomography angiography of the peripapillary retina and optic nerve head in Wolfram syndrome

Purpose To evaluate the peripapillary and optic nerve head (ONH) microcirculation in patients affected by Wolfram syndrome and to correlate the results with the functional and anatomical conventional imaging: visual field (VF) and structural optical coherence tomography (OCT). Methods This study reports two cases of siblings with wolfram syndrome. They underwent a complete ophthalmological examination and an automated perimetry. A measure of peripapillary retinal nerve fiber layer (RNFL) thickness using a Swept- Source OCT was performed. Optical coherence tomography angiography (OCT-A) images were obtained using a Swept-Source DRI OCT Triton (Topcon Corporation, Japan). The scan size of optic disc area was 6 mm × 6 mm and he was divided into four layers, which were optic nerve head (ONH), vitreous, radial peripapillary capillary (RPC), and choroid layers. Peripapillary and nerve head vessels density were evaluated. Results The first case is a 57 years old female patient with a history of diabetes insipidus and deafness, suffering from bilateral progressive visual loss. On fundoscopic examination, she had bilateral optic atrophy. Her visual acuity was reduced to 0.4 on both eyes. Her visual fields demonstrated generalized constriction. There was a family history of similar conditions. Her brother, a 46 years old male has a similar course of disease. The two patients had sectorial (temporal and inferior) optic atrophy based on the RNFL thinning detected by OCT. OCT-A scans showed a decrease of the vascular network in the ONH and in the RPC layers corresponding to the sector of RNFL thinning. Conclusions Peripapillary and optic nerve head temporal and inferior microvascular network were reduced in Wolfram patients. These findings confirm the preferential involvement of the small axons of the papillomacular bundle in dominant optic atrophy.

SS – OCT angiography in retinal dystrophies with macular edema or cysts

Purpose To analyze swept source optical coherence tomography angiography (SS – OCT-A) findings in retinal dystrophies with macular edema or cysts. Methods Optical coherence tomography angiography and structural OCT were performed using a Swept-source DRI OCT Triton (Topcon, Corporation, Japan) for 3 patients with retinitis pigmentosa and macular edema, 3 patients with enhanced S-cone syndrome and 1 patient with X-linked retinoschisis. Results In all patients, changes were more pronounced in the deep plexus where macular edema was more evident. Also, there was focal dislocation of the vascular network in correspondence with the serous intraretinal cysts. In patients with retinitis pigmentosa, capillary were visible at the top of the cysts. On the other hand, in case of X-linked retinoschisis, we found wheel-like cystoids cavities separated by apparently well-vascularized walls with a good correspondence with structural en face OCT. Conclusions OCT-A may provide information of great interest in inherited retinal dystrophies with macular edema or cysts. It reveals particular alterations above all located at the level of the deep capillary plexus and the choriocapillaris. Such information may be useful for phenotyping each case and understanding pathogenesis of cysts development in each dystrophy helping their future therapeutic management.