Photoreceptor Structure in Presumed Non-Neoplastic Autoimmune Retinopathy

Abstract

Purpose: Autoimmune retinopathies (AIR) are rare diseases, sometimes associated with systemic neoplasms, in which anti-retinal antibodies lead to cone and rod dysfunction. Patients present with progressive, bilateral, painless vision loss despite normal clinical fundus appearance, making diagnosis difficult. SD-OCT has shown outer retinal abnormalities and decreased macular thickness in AIR patients. Adaptive optics scanning light ophthalmoscopy (AOSLO) enables high-resolution imaging of the photoreceptor mosaic. This study incorporates AOSLO into the comprehensive investigation of individuals with AIR to evaluate its utility in improving the characterization and management of AIR.

Methods: Three individuals with presumed non-neoplastic AIR who presented with vision loss, normal fundus appearance and known anti-retinal antibodies underwent a comprehensive ophthalmic evaluation and multiple retinal imaging sessions over a 5 - 14 month interval. Retinal appearance and lamination were assessed using fundus photography and SD-OCT. The photoreceptor mosaic was assessed using AOSLO.

Results: All three individuals had different anti-retinal antibody combinations in serum, and presenting vision ranged from 20/40 to 20/100. Clinical and fundus photography evaluation confirmed normal appearing fundus. SD-OCT revealed decreased central macular thickness in two of the three patients, and focal disruption of outer retinal lamination was seen at the fovea in all patients. This disruption was also visible in the AOSLO images as a large hyporeflective area at the fovea. In addition, AOSLO images revealed significant reduction in parafoveal cone density in all three subjects, with variable numbers of non-waveguiding cones interspersed throughout the mosaic. This disruption was not visualized on SD-OCT.

Conclusions: Both SD-OCT and AOSLO show outer retinal structure changes associated with AIR not apparent on clinical examination. However, AOSLO allows for assessment of photoreceptor structure at a resolution not resolvable on SD-OCT. AOSLO may prove to be a useful, noninvasive, highly accurate tool to aid in diagnosis of AIR as well as monitoring progression and treatment responses. Further study is needed to determine whether AOSLO can be used to accurately track progression of photoreceptor disruption in AIR over time.

Keywords: 432 autoimmune disease • 550 imaging/image analysis: clinical • 689 retina: distal (photoreceptors, horizontal cells, bipolar cells)