Reversibility of retinochoroidal vascular alteration in patients with obstructive sleep apnea after continuous positive air pressure and surgical intervention

Purpose: The aim of this work was to study various retinochoroidal parameters in patients with obstructive sleep apnea syndrome (OSAS) and the effect of interventions on these parameters at 6 months follow-up. Methods: A total of 36 patients were recruited prospectively from the otorhinolaryngology clinics of a large tertiary center between September 2018 to March 2020. The subjects were divided into three groups depending upon intervention chosen for OSAS: Group A (surgery, i.e., uvulopalatopharyngoplasty), group B (medical therapy, i.e., continuous positive air pressure) and group C (no intervention). Various retinochoroidal parameters which were studied included retinal thickness (RT), choroidal thickness (CT), choroidal vascularity index (CVI), arteriovenous ratio (AVR), capillary density index (CDI) in superficial and deep retina, at baseline and 6 months of follow-up after the intervention. Results: In group A, CT increased significantly at 6 months (332.76 ± 86.41 um) compared to baseline (306.28 ± 78.19) (P = 0.0004). Similarly, CDI at both superficial and deep capillary plexus increased significantly at 6 months (superficial CDI: 0.65 ± 0.04, deep CDI: 0.38 ± 0.01) compared to baseline (superficial CDI: 0.62 ± 0.03, deep CDI: 0.36 ± 0.02) (P = 0.004 and 0.002 respectively). In group B, CT increased significantly at 6 months (361.38 ± 78.63 um) compared to baseline (324.21 ± 76.97 um) (P = 0.008). Also, CVI showed a significant decrease at 6 months (65.74 ± 1.84%) compared to baseline (67.36 ± 1.57%) (P = 0.019). In group C, all except CDI in deep capillary plexus showed a significant decrease at 6 months (0.35 ± 0.01) compared to baseline (0.36 ± 0.02) (P = 0.003). Conclusion: OSAS alters various retinochoroidal parameters and timely intervention in patients with OSAS can prevent these alterations. Also, these retinochoroidal parameters could serve as one of the markers to monitor the disease progression.