Normal intraocular pressure is a fundamental and important concept and variable of the intraocular pressure and even total glaucoma system.This article deals with certain problems in our understanding the normal intraocular pressure such as its population-based central tendency,right-skewed distribution and diurnal fluctuation,and its relationship to normal pressure glaucoma, ocular hypertension and target pressure.It is emphasized that"normal intraocular pressure"is not a simple numeric range and not confined to the upper limit for clinical values.The normal intraocular pressure remains to be thoroughly understood for its profound implications.(Ophthalmol CHN,2008,17:6-9)

Objective To investigate the relationship between optic d isc hemorrhage and localized retinal never fiber layer defects (RNFLDs) in norma l-tension glaucoma. Methods In 83 patients with normal-tensi on glaucoma, the cumulative frequency and quadrantal distribution of optic disc hemorrhages were retrospectively analyzed. The neighboring relation between opti c disc hemorrhages and RNFLDs in a same quadrant and the changes of correspondin g retinal never fiber layer (RNFL) after the occurrence of optic disc hemorrhage s were observed by tridimensional photochromy of ocular fundus. Results (1) The occurrences and distribution of optic disc hemorrhages: 29 of 83(34.94%) patients (33 eyes) had totally 58 occurrences, including 39 in infer iotemporal area, 14 in superiotemporal area, and 5 in other area. (2) The relati onship of neighborhood between optic disc hemorrhages and RNFLDs: in the availab le tridimensional photochrome, 23 occurrences in 15 patients (16 eyes) were foun d with cuneiform RNFLDs in the same quadrant, in which 22 was near the border of cuneiform RNFLDs. (3) The changes of corresponding retinal never fiber layer (R NFL) after the occurrence of optic disc hemorrhages: the photochromes of 24 occu rrences in 20 patients (21 eyes) were kept well in the initial and the 2-year f ollow-up periods, while the changes of RNFL were found in each region correspon ding to the 19 occurrences (in inferiotemporal or superiotemporal area) in the i nitial photochrome, including 7 cuneiform defects with various sizes, and 12 dev eloped localized RNFLDs next to the initial hemorrhages in the optic disc. No ob vious localized RNFL corresponding to the other 5 occurrences (1 in inferiotempo ral, 1 in superiotemporal, and 3 in other areas) were found in the follow-up pe riod. Conclusion Optic disc hemorrhages in normal-tension gla ucoma occur mostly in inferiotemporal area, and secondly in superiotemporal area of optic disc, and the appearance of optic disc hemorrhages may suggest that th e localized RNFLDs would develop in the associated regions.

OBJECTIVE: To investigate accuracy of the currently used strategies for intraocular pressure measurements for reflecting actual 24-hour intraocular pressure fluctuations. METHODS: From September, 2018 to January, 2019, the patients with a suspected diagnosis of primary open angle glaucoma at our hospital were prospectively enrolled to receive 24-hour intraocular pressure monitoring using a Goldmann tonometer. With the intraocular pressure measurements at 0:00, 2:00, 5:00, 7:00, 8:00, 10:00, 11:00, 14:00, 16:00, 18:00, 20:00, and 22:00 as the gold standard (strategy 1), we compared the measurements taken at 5:00, 7:00, 10:00, 14:00, 18:00, and 22:00 (strategy 2) and at 8:00, 11:00, 14:00, and 16:00 (strategy 3) for their accuracy in reflecting 24-h intraocular pressure fluctuations. RESULTS: A total of 41 patients (82 eyes) were enrolled in this study. The peak intraocular pressures measured using the 3 strategies were 21.09±4.15 mmHg, 20.54±4.10 mmHg, and 19.91±4.38 mmHg, respectively, showing significant differences among them ( CONCLUSIONS For suspected cases of glaucoma, intraocular pressure measurements at 4 and 6 time points of a day can not precisely reflect the actual range of intraocular pressure fluctuations, and may lead to a missed diagnosis of glaucoma.
Glaucoma/diagnosis* ; Glaucoma, Open-Angle ; Humans ; Intraocular Pressure ; Prospective Studies ; Tonometry, Ocular