Twenty-four-hour ocular perfusion pressure in primary open-angle glaucoma

Aim: To compare the 24 h intraocular pressure (IOP), blood pressure (BP), and perfusion pressure (PP) of primary open-angle glaucoma (POAG) patients and healthy individuals. Methods: 24 healthy individuals and 29 POAG patients underwent IOP and BP measurements every 2 h, starting at 08:00 until 06:00 of the next morning. IOP measurements were made by a masked observer with a Goldmann tonometer at the slit-lamp from 08:00 to 22:00 and with the Perkins tonometer in supine position from 24:00 to 06:00. Systolic and diastolic BP (SBP and DBP) measurements were performed with an automated device. Results: Mean IOPs in POAG patients were significantly higher at all time intervals (p<0.001). The mean SBP was significantly higher in POAG patients from 04:00 to 10:00, and also at 14:00 and 18:00 (p<0.05). In POAG patients, the mean DBP was significantly higher at 08:00 and 10:00, but was significantly lower at 04:00 (p<0.05). In POAG patients, the mean systolic perfusion pressure (SPP) was significantly higher at 08:00 and 10:00 (p<0.01), whereas the mean diastolic perfusion pressure (DPP) was significantly lower from 24:00 to 06:00 (p<0.05). Conclusion Although higher SPPs are observed in POAG patients during the morning, lower DPPs are found during the night.