Abstract
Purpose: :
Obstructive sleep apnea syndrome (OSA) has been reported to be associated with ischemic and glaucomatous optic neuropathy (especially normal tension glaucoma). OSA per se is able to generate hypertension, atherosclerosis and autonomic dysfunction, all conditions possibly interacting with ocular vascular regulation. The aim of our study was to characterize the choroidal vascular reactivity to change in body position in OSA patients, as compared with matched healthy control subjects.
Methods: :
Eighteen newly diagnosed OSA patients were included in this prospective study. Control subjects were matched with OSA patients for body mass index (BMI), gender and age. At the screening visit, each subject underwent a general exam, cardiovascular, neurologic and ophthalmological examinations, and overnight polysomnography.The LDF instrument used in this study to measure subfoveal choroidal blood flow (ChBF), ChBVel , velocity (kHz); and volume, ChBVol (in arbitrary units, AU) Vascular choroidal reactivity was tested during the change in body position from the sitting to the supine position (10 min).
Results: :
OSA patients exhibited a similar choroidal reactivity during change in body position than controls with increased ChBVel (+14%), decreased ChBVol (-12%), and unchanged ChBF.
Conclusions: :
This prospective comparative study showed for the first time unimpaired choroidal vascular reactivity in otherwise healthy OSA patients. This suggests OSA patients, without comorbidities, has long-term adaptive mechanisms active in ocular microcirculation.
Keywords: choroid • hypoxia • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)