ISSN: 2578-465X
Insight into Macular Vascular Changes Seen in Retinitis Pigmentosa Using OCTA
Statement of Significance: Optical Coherence Tomography Angiography (OCTA) allows for compete assessment of macular vascular density of various stages of retinitis pigmentosa.
Purpose: Retinitis pigmentosa (RP) is an inherited retinal dystrophy characterized by progressive degeneration of the rod photoreceptor cells with eventual degeneration of cone photoreceptors as well. The advent of Optical Coherence Tomography Angiography (OCTA) has provided new insight into the pathophysiology behind the disease including disorganization within the inner retina that coincides with morphological changes within the outer retina and photoreceptors. Furthermore, retinal vascular alterations within the inner retina appear to be directly correlated with visual function in affected patients.
Case Report: Three patients with varying stages of RP are presented. Patients were evaluated and categorized based on visual acuity, funduscopic findings, electrodiagnostics, OCT and OCTA. Vascular density within the retinal and choroidal vessels was evaluated with the Spectral-Domain Optical Coherence Tomography Angiography with XR Avanti (Optovue, Inc., Fremont, CA, USA). Degree of vascular reduction within the inner retinal SCP (superficial capillary density) and DCP (deep capillary density) was directly correlated with stage of disease and visual function.
Conclusions: Vascular alterations including arterial narrowing, vessel attenuation and changes in blood flow have been well documented in RP patients. OCTA now provides a 3-dimensional volumetric analysis of retinal blood flow throughout all layers of the retina allowing for direct correlation between structure and vascular integrity. The correlation between inner retinal integrity, vascular structure and visual function can be optimally examined with the integration of OCTA and treatment modalities can be appropriately aimed at targeting viable retinal photoreceptors.
Keywords:
Retinitis Pigmentosa; Optical Coherence Tomography Angiography; Funduscopic; Choroidal; Nyctalopia
