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Does severe obstructive sleep apnea syndrome alter retrobulbar blood flow? A color Doppler ultrasound study
Bülent Çekiç1, Ömer Tarık Selçuk2, İclal Erdem Toslak3
1Department of Radiology, Antalya Education and Training Hospital, Medical Sciences University, 070030, Antalya, Turkey. bulend71@yahoo.com.
Purpose:
To evaluate extraocular orbital vessels with color Doppler ultrasound (CDU) and investigate the effects of severe obstructive sleep apnea (OSA) on retrobulbar blood flow.
Methods:
Between February 2014 and September 2015, 30 patients with severe OSA (apnea-hypopnea index (AHI) > 30) and 28 controls were prospectively included in this study. Intraocular pressure (IOP) was measured with a Goldmann applanation tonometer, and CDU was used to evaluate the retrobulbar vessels.
Results:
The mean AHI score for the OSA group was 63.2 ± 21.5 per hour. The IOP values were significantly higher in the severe OSA group (p < 0.05). The central retinal artery peak systolic velocity (PSV) (p < 0.05) and end-diastolic velocity (EDV) (p < 0.02), and the ophthalmic artery (OA) PSV and EDV, were found to be significantly lower in the OSA group (p < 0.05).
Conclusion:
Severe OSA causes an increase in IOP and a decrease in flow velocity in the retrobulbar circulation.
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