Optical coherence tomographic evaluation of the outer retinal architecture in Oguchi disease

Abstract

Background

To report the changes in the optical coherence tomography (OCT) images of the outer retinal layers after prolonged dark adaptation in a patient with Oguchi disease.

Case

A 75-year-old woman showed the typical golden-yellow fundus reflex of Oguchi disease, and the coloration returned to normal after prolonged dark adaptation. Fourier domain OCT (FD-OCT) was performed on the patient’s left eye before and after prolonged dark adaptation.

Observations

Before dark adaptation, the FD-OCT images at the fovea had three identifiable reflection bands, namely, the external limiting membrane (ELM), the border between the photoreceptor inner and outer segments (IS/OS line), and the retinal pigment epithelium (RPE)/Bruch band. The paramacular area had only the ELM and RPE/Bruch bands. After 4 h of dark adaptation, the IS/OS line was also detected in the paramacular area.

Conclusions

The absence of the IS/OS line in the extramacular regions in the partly dark adapted condition was most likely due to a defect in the rod photoreceptors of this area. The emergence of the IS/OS line after prolonged dark adaptation suggests that microarchitectural changes occur in the photoreceptors and that the changes may be correlated with the improvement of rod function.