Abstract:

Objective To characterize the circadian fluctuation of ocular perfusion pressure (OPP) in different position  in patients with newly diagnosed, untreatedprimary open-angle glaucoma（POAG）. Design Cohort study. Participants Nineteen patients with POAG (19 eyes) and eighteen healthy controls (18 eyes) were included in the Peking University Shenzhen Hospital. Methods POAG patients and healthy controls were included and underwent 24-hour monitoring of IOP and blood pressure. On 10:00, 14:00, 18:00 and 22:00 o’clock in the daytime, all the subjects were monitored in sitting position, then POAG patients were monitored again after lying down for 5 minutes. On 2:00, 5:00 and 7:00 o’clock at night all the subjects were monitored in supine position, then POAG patients were monitored again after sitting for 5 minutes. Calculating the mean ocular perfusion pressure (MOPP), the systolic ocular perfusion pressure (SOPP) and diastolic perfusion pressure (DOPP) by the formula and analyzing the data. Main Outcome Measures  MOPP, SOPP, DOPP. Results In both groups of habitual position (sitting position in day and supine position in night), the nocturnal MOPP, SOPP and DOPP were lower than diurnal. In both groups, the nocturnal MOPP was lower than diurnal in habitual position (POAG group t=4.092, P=0.000; healthy group t=4.513, P=0.000). However, there was no obvious difference between those two groups (t=-0.973, P=0.350). POAG group had higher 24-hour fluctuation of MOPP (t=2.204, P=0.039), higher nocturnal fluctuation of SOPP (t=3.097, P=0.018), higher nocturnal and 24-hour fluctuation of DOPP than healthy group, all the differences had statistical significance (all P<0.05).  In POAG group , there was no statistical difference between the nocturnal MOPP and the diurnal MOPP in sitting position or in supine position of 24 h (all P>0.05). POAG group had higher 24-hour mean MOPP in sitting position than in supine position, the difference had statistical significance (t=4.306, P=0.001).  Comparing the MOPP of  POAG group  in habitual position with in sitting position of 24 h, there was no statistical difference(t=-2.101, P=0.080). However, POAG group had higher 24-hour mean MOPP in habitual position than in supine position of 24 h, the difference had statistical significance (t=2.707, P=0.035). Conclusions There circadian fluctuation of  OPP in different position in POAG pations can not be treated as the same. The nocturnal MOPP  was lower than diurnal in habitual position, but there was no obvious difference in the 24h-sitting position and 24h-supine position.  (Ophthalmol CHN, 2017, 26: 20-25）

Key words: primary open-angle glaucoma, position, ocular perfusion pressure