Abstract
Purpose:
Characterize retinal structure and function in a patient with gyrate atrophy using high resolution clinical imaging and adaptive optics scanning laser ophthalmoscopy (AOSLO).
Methods:
A patient with gyrate atrophy was imaged at several retinal locations within 1.5mm of fixation using an AOSLO developed by Canon Inc. Infrared (IR) fundus photography, spectral domain optical coherence tomography (OCT), and autofluorescence (AF) images were also obtained. Wide field SLO reflectance and AF images were acquired using the Optos P200C SLO. Retinal sensitivity was assessed by microperimetry at the locations corresponding to AOSLO images.
Results:
The patient had a peripheral ring of degenerated retina, with central preservation of both retinal pigment epithelium (RPE) and photoreceptors. Wide field SLO imaging also revealed retinal preservation in the far periphery. Within the ring of degeneration, the retina displayed hypo-AF with RPE disruption. Microperimetry displayed vision loss in this region. Choroidal vessels were visible on AOSLO in the region of degeneration; no cones were observed in these areas. In contrast, the spared central retinal on fundus photography corresponded to regions with preserved AF. AOSLO imaging confirmed cones in this region, including near the border of healthy and degenerated retina. Cone density was normal throughout most of the preserved retina, with slightly lower density at regions bordering degenerated retina. Photoreceptor and RPE cell layers appeared intact on OCT in the region of the central macula, although there were disruptions of the retinal architecture including cysts. Abnormal hyper-reflective patches were observed at multiple levels of retinal depth anterior to the photoreceptors, in multiple locations including the fovea. At these locations, the patient had slightly reduced light perception, as assessed by microperimetry.
Conclusions:
This patient with gyrate atrophy maintained photoreceptors and RPE cells centrally, although both are lost in a ring pattern in the periphery. Cones are visible with AOSLO until the point of RPE loss, as seen with AF. Gyrate atrophy is associated with findings in multiple levels of the retina, visible by both AOSLO and OCT. AOSLO imaging in combination with other imaging modalities will be useful to monitor disease progression, and provide a measure of cone loss over time in patients with gyrate atrophy.
Keywords: 550 imaging/image analysis: clinical •
696 retinal degenerations: hereditary •
648 photoreceptors