Komplet Tip Konjenital Durağan Gece Körlüğü Hastalarının Klinik Özellikleri ve Spektral Domain Optik Koherens Tomografi Bulguları

Abstract

Objective: To describe clinical findings and spectral domain optical coherence tomography (SD-OCT) features of our complete congenital stationary night blindness (CSNB) patients. Material and Methods: This retrospective study included 12 eyes of six patients diagnosed with complete type CSNB. Patients were evaluated with SD-OCT, fundus autofluorescence (FAF) and electrophysiological tests. Segmentation of retinal layers was performed on SD-OCT images of all CSNB patients and compared with 6 age matched, normal myopic controls. Results: All patients' anterior segments findings were normal and none of our patients had nystagmus or strabismus. Pale optic disc was observed in two patients. On FAF imaging eyes with CSNB demonstrated unremarkable fundi including normal distribution of autofluorescence. Full-field electroretinography (ERG) demonstrated b-wave to a-wave amplitude ratio of less than one in the combined rod?cone response which describes electronegative ERG. SD-OCT segmentation revealed statistically significant thinning of the total retina, retinal nerve fiber layer (RNFL), inner plexiform layer (IPL) and inner retinal thicknesses in the CSNB group compared to control group (respectively p=0.015, p=0.011, p=0.017 and p=0.021). In the other layers of retina, we observed thinning in the CSNB group, but this difference was not statistically significant. Conclusion: In our study we observed selective thinning of RNFL and IPL in our patients. We thought that thinning of the IPL and RNFL and possibly optic disc paleness in complete CSNB patients suggests bipolar cell dysfunction or synaptogenesis defect between bipolar cells and ganglion cells and possibly reduced number of these cells.