Evaluation of orbital doppler ultrasonography and optical coherence tomography findings in obstructive sleep apnea syndrome

Purpose: Our aim is to evaluate orbital blood flow with Doppler ultrasonography and display it' s relationship with retinal nerve fiber layer and ganglion cell layer in obstructive sleep apnea patients. Material-metod: Among 143 patients who was diagnosed for OSAS at polysomnography, exclusion criteria including hypertension, diabetes, steroid use and previous eye disease or surgery is used. Control group was chosen matched for age and sex with patients group. Peak systolic, end diastolic velocities and resistivity indices was measured at ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary artery (PCA) with Doppler ultrasonography. Additionally; routine ophthalmic examination including intraoculary pressure and optic coherence tomography (OCT) for retinal nerve fiber layer thickness and ganglion cell layer volumes are performed. Results: 29 patients and 29 healthy control subjects was chosen among exculision criteria. All of our patients and control subjects had normal intraoculary pressure. OCT revealed no difference between RNFL thickness between OSAS patients and control groups (p=0,888), but ganglion cell layer volume at the center was higher in OSAS group (p=0,033). Similarly, CRA RI values are not significantly different between two groups(p= 0,687), but in OSAS group, RGCL central volume and CRA RI was negatively correlated(p=0,023, r= -309). As we grouped OSAS patients mild-moderate and severe and compare with control group, RGCL central 1 mm circular area's volume is increased in the mild-moderate group than decreased in severe OSAS group (p=0,019). CRA PSV is decreased at mild-moderate OSAS than controls and increased in severe group (p=0,010). Conclution: Even though orbita is clinically normal, changes starts to occure in ganglion cells at OCT and this finding can be supported with Doppler ultrasonography.