Obstructive sleep apnea syndrome (OSAS) may result in lower vascular densities in both the superficial and deep capillary plexus and a larger deep capillary plexus foveal avascular zone (FAZ), according to a study published in Photodiagnosis and Photodynamic Therapy.
Researchers enrolled 56 patients with OSAS and 26 controls in the study. They measured vascular densities of the superficial and deep capillary plexus along with FAZ width for all participants using optical coherence tomography-angiography (OCT-A). Investigators stratified patients with OSAS into 3 groups based on the severity of the disorder; mild (n=21), moderate (n=14), and severe (n=21).
Researchers noted that the vascular density in the whole image of the superficial capillary plexus was significantly lower in participants with moderate OSAS compared with the control group (P =.019), and a lower vascular density in the foveal region of the superficial capillary plexus in participants with mild OSAS compared with the control group (P =.006). They also observed a larger FAZ in the deep capillary plexus in those with mild and severe OSAS compared with controls (P =.010 and P =.015, respectively) and significantly decreased vascular densities in the parafoveal region in those with severe OSAS compared with controls (P =.048).
Investigators stress the importance of understanding the effect OSAS has on retinal microvasculature and state, “Our results might draw attention of the clinicians to the follow up of the OSAS patients for retinal diseases and considering OCTA as useful and a non-invasive method for these patients.”
Limitations of the study include the small sample size and lack of blood pressure measurements.
Ava S, Erdem S, Karahan M, et al. Evaluation of the effect of obstructive sleep apnea syndrome on retinal microvascularity by optical coherence tomography angiography. Photodiagnosis Photodyn Ther. Published online February 15, 2022. doi:10.1016/j.pdpdt.2022.102761.