Effects of Hypoxia on the Eye in Patients with Obstructive Sleep Apnea Syndrome

Objective: Hypoxia, perfusion pressure changes, systemic hypertension, vasospasm, increase in blood viscosity and small vessels' resistance may cause ischemia in Obstructive sleep apnea syndrome (OSAS). The aim of this study is to assess the effect of hypoxia on the eye (choroidal and corneal thicknesses) in patients with OSAS. Materials and Methods: In this observational study age and gender-matched 20 severe, 17 modarate, 16 mild OSAS patients without any comorbidity and a control group of 16 healthy subjects were examined with spectral-domain optic coherence tomography (OCT). The central corneal thickness (CCT), subfoveal, and temporal and nasal choroidal thicknesses of the patients were measured by OCT. Results: The mean age of OSAS patients was 52.3 +/- 10.6 and 48.8 +/- 12.1 in control subjects. Female and male patients made up 23.1% and 76.9%, respectively. The mean CCT of OSAS patients was 560.2 +/- 31.1/563.5 +/- 29.1 mu m, whereas the mean CCT was 560.6 +/- 30.4/567.1 +/- 28.2 mu m in control group (p=0.52/p=0.29). There were significant differences (p<0.001) in choroidal thickness (severe: 228.3 +/- 16.8/240.5 +/- 17.8; moderate: 236.0 +/- 21.6/232.4 +/- 18.5; mild: 241.3 +/- 23.6/242.6 +/- 20.9; control: 267.8 +/- 18.6/271.6 +/- 18,6 mu m) between patients and control groups who were separated by their OSAS severity. .Conclusion: In our study choroidal thickness became thinner with increasing OSAS severity. On the other hand, corneal thickness did not seem to be affected from OSAS.