AIM: To analyze the value of 24-hour intraocular pressure(IOP)monitoring in suspected glaucoma patients.

METHODS: Totally 48 suspected glaucoma(96 eyes)were selected for 24-hour IOP monitoring by using Accupen tonometer(24-3000)and non-contact tonometer(NCT, CT-80A)from 9:30 to 7:30 next day(once in 2h). During 07:30 to 21:30, patients were measured in sitting position, while during 23:30 to 05:30 in both sitting and supine position.

RESULTS: A morning peak of IOP was shown at 7:30 in traditional position by using two measures with 22.05±3.608mmHg of NCT and 19.79±4.147mmHg of Accupen tonometer. The peak IOP in habitual position appeared in 5:30 with 21.64±4.814mmHg. The lowest IOP occurred in both position at 21:30 with 15.73±3.649mmHg. Both positions showed IOP trend of going up at night and then declining in the morning.

CONCLUSION: The peak IOP in suspected glaucoma occurs mostly at early morning. Supine IOP of sleeping time is higher than that of sitting position.