Circadian Intraocular Pressure Profiles in Chronic Open Angle Glaucomas

Purpose: to evaluate circadian intraocular pressure (iop) profiles in eyes withdifferent types of chronic open-angle glaucoma (coag) and normal eyes.methods: this study included 3,561 circadian iop profiles obtained from 1,408 eyesof 720 caucasian individuals including glaucoma patients under topical treatment(1,072 eyes) and normal subjects (336 eyes). iop profiles were obtained by goldmannapplanation tonometry and included measurements at 7 am, noon, 5 pm, 9 pm, andmidnight.results: fluctuations of circadian iop in the secondary open-angle glaucoma (soag)group (6.96±3.69 mmhg) was significantly (p<0.001) higher than that of the normalpressure glaucoma group (4.89±1.99 mmhg) and normal eyes (4.69±1.95 mmhg); but the difference between the two latter groups was not significant (p=0.47). expressedas percentages, iop fluctuations did not vary significantly among any of the study groups. inter-ocular iop difference for any measurement was significantly (p<0.001)smaller than the profile fluctuations. in all study groups except the soag group,iop was highest at 7 am, followed by noon, 5 pm, and finally 9 pm or midnight. inthe soag group, mean iop measurements did not vary significantly during dayand night.conclusions: in contrast to normal eyes and eyes with primary open-angle glaucomaunder topical antiglaucoma treatment, eyes with soag under topical treatment donot show the usual circadian iop profile in which the highest iop values occur inthe morning, and the lowest in the evening or at midnight. these findings may haveimplications for timing of tonometry. fluctuation of circadian iop was highest insoag compared to other types of open angle glaucomas.