Inter-eye differences in chronic open-angle glaucoma patients with unilateral disc hemorrhages

Inter-eye Differences in Chronic Open-angle Glaucoma Patients with Unilateral Disc Hemorrhages Jost B. Jonas, MD,1,2 Peter Martus, PhD,3 Wido M. Budde, MD1 Objective: Flame-shaped optic disc hemorrhages are a hallmark of glaucomatous optic neuropathy. The purpose of this study was to evaluate which parameters differ between companion eyes with and without an optic disc hemorrhage in patients with chronic open-angle glaucoma. Design: Comparative (companion eye) observational case series. Patients: The study included 99 white patients with bilateral chronic open-angle glaucoma and unilateral flame-shaped optic disc hemorrhages. Methods: All patients underwent qualitative and morphometric evaluation of color stereo optic disc photographs. Main Outcome Measures: Size and shape of the optic disc, neuroretinal rim and parapapillary atrophy, diameter of the retinal vessels, intraocular pressure measurements, and both mean value and loss variance value of the visual field examination. Results: In an intraindividual inter-eye comparison, the eyes with disc hemorrhages and the contralateral eyes without disc bleeding did not vary significantly (P ⬎ 0.20) in size and shape of the optic disc and neuroretinal rim, optic cup depth, size of alpha and beta zone of parapapillary atrophy, retinal vessel diameter, intraocular pressure measurements, refractive error, and perimetric indices. Conclusions: In bilateral chronic open-angle glaucoma, the development of unilateral optic disc hemorrhages does not depend on inter-eye differences in size and shape of the optic disc, neuroretinal rim and parapapillary atrophy, diameter of the retinal vessels, intraocular pressure measurements, or visual field loss. Ophthalmology 2002;109:2078 –2083 © 2002 by the American Academy of Ophthalmology, Inc.

Flame-shaped or splinter-like hemorrhages at the optic disc border are a characteristic sign of glaucomatous changes at the optic nerve head.1–10 Rarely found in normal eyes,11–13 disc hemorrhages are detected in approximately 4% to 7% of eyes with glaucoma.14 Their frequency increases from an early stage of glaucoma to a medium-advanced stage and decreases again toward a far-advanced stage. In early glaucoma, they are usually located in the inferotemporal or superotemporal disc regions. They are associated with localized retinal nerve fiber layer defects, neuroretinal rim notches, and circumscribed perimetric loss.15,16 The diagnostic importance of disc hemorrhages is based on their

Originally received: October 4, 2001. Accepted: March 29, 2002.

high specificity, because they are only rarely found in normal eyes; that they usually indicate the presence of glaucomatous optic nerve damage, even if the visual field is unremarkable;17–21 and it is based on the fact that they suggest progression of glaucoma.8,10,16,21,22–24 The pathogenesis of the flame-shaped optic disc hemorrhages has not been clearly explained yet. In an attempt to find factors that may predispose to, or that are associated with, the development of optic disc hemorrhages in glaucoma, we undertook this study to evaluate in which parameters the eyes with disc hemorrhages and the contralateral eyes without disc hemorrhages in patients with bilateral open-angle glaucoma and unilateral optic disc hemorrhages differ.

Manuscript no. 210842.

1

Department of Ophthalmology and Eye Hospital, University ErlangenNu¨rnberg, Germany.

Materials and Methods

2

The clinical observational study included 99 white patients (60 women, 39 men; 198 eyes) with chronic open-angle glaucoma, who showed a flame-shaped hemorrhage touching the optic disc border at the time of presentation. All patients had an open anterior chamber angle and were consecutively evaluated. The mean age was 60.9 ⫾ 14.0 years (median, 63 years; range, 15– 84 years); mean refractive error was ⫺0.45 ⫾ 2.00 diopters (median, 0 diopters; range, ⫺9.0 –⫹3.1 diopters). The methods applied in the study adhered to the tenets of the Declaration of Helsinki for the

Department of Ophthalmology and Eye Hospital, Faculty of Clinical Medicine Mannheim, University of Heidelberg, Mannheim, Germany.

3

Department for Medical Informatics, Biometry, and Epidemiology, Medical Faculty, Free University of Berlin, Berlin,Germany. Supported by Deutsche Forschungsgemeinschaft DFG (SFB 539), Bonn, Germany. Reprint requests to Dr. J. Jonas, Universita¨ts-Augenklinik, TheodorKutzer-Ufer 1-3, 68167 Mannheim, Germany. E-mail: Jost.Jonas@augen. ma.uni-heidelberg.de.

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© 2002 by the American Academy of Ophthalmology, Inc. Published by Elsevier Science Inc.

ISSN 0161-6420/02/$–see front matter PII S0161-6420(02)01237-X

Jonas et al 䡠 Inter-eye Differences in Unilateral Glaucomatous Disc Hemorrhages use of human subjects in biomedical research. Informed consent was obtained from each subject before enrollment. Institutional review board/ethics committee approval was not required for this study. The patients were part of an ongoing prospective study on the biomorphometry of the optic nerve in glaucoma (Erlangen Glaucoma Register). The entire study group consisted of 25 (12.6%) of 198 eyes with preperimetric glaucoma defined by glaucomatous abnormalities of the optic nerve head and normal white-on-white visual fields, and 173 (87.4%) of 198 eyes with chronic open-angle glaucoma with glaucomatous visual field defects. Glaucomatous changes of the optic nerve head included an unusually small neuroretinal rim area in relation to the optic disc size, an abnormal shape of the neuroretinal rim, cup-to-disc diameter ratios that were vertically higher than horizontal, and localized or diffuse retinal nerve fiber layer defects.1 A glaucomatous visual field defect was defined as an Octopus G1 field with (1) at least three adjacent test points having a deviation of equal to or greater than 5 dB and with one test point with a deviation greater than 10 dB, (2) at least two adjacent test points with a deviation equal to or greater than 10 dB, (3) at least three adjacent test points with a deviation equal to or greater than 5 dB abutting the nasal horizontal meridian, or (4) a mean visual field defect of more than 2 dB. The rate of falsepositive answers and the rate of false-negative answers had to be equal to or less than 15%. The entire study group was additionally divided into eyes with primary open-angle glaucoma (n ⫽ 118, 59.6%), secondary openangle glaucoma caused by reasons such as pseudoexfoliation or primary melanin pigment dispersion syndrome (n ⫽ 16, 8.1%), and normal-pressure glaucoma (n ⫽ 64, 32.3%). In the eyes affected by primary open-angle glaucoma, no obvious reason for the elevated intraocular pressure could be detected. Criteria for the diagnosis of normal-pressure glaucoma were maximal intraocular pressure readings equal to or less than 21 mmHg in at least two 24-hour pressure profiles obtained by slit-lamp applanation tonometry and containing measurements at 5 pm, 9 pm, midnight, 7 am, and noon. Ophthalmoscopy, medical history, and neuroradiologic, neurologic, and medical examinations did not reveal any other reason, such as intrasellar or suprasellar tumors, retinal vessel occlusions, optic disc drusen, or nonarteritic anterior ischemic optic neuropathy, for optic nerve damage other than glaucoma. For all eyes, 15° color stereo optic disc transparencies had been taken using a Zeiss telocentric fundus camera (30° fundus camera, equipped with a 15° converter; Zeiss, Oberkochen, Germany). The disc slides were projected in a scale of 1 to 15. The outlines of the optic cup, optic disc, peripapillary scleral ring, and alpha zone and beta zone of parapapillary atrophy were plotted on paper and morphometrically analyzed. To obtain values in absolute size units (i.e., millimeter or square millimeter), the ocular and photographic magnification was corrected using the Littmann method.25 The optic cup was defined on the basis of contour and not of pallor. The border of the optic disc was identical with the inner side of the peripapillary scleral ring. Parapapillary atrophy was differentiated into a peripheral alpha zone with irregular pigmentation and a central beta zone with visible sclera and visible large choroidal vessels. To assess the configuration and the regional distribution of the neuroretinal rim and parapapillary atrophy, the optic disc and the parapapillary region were divided into four sectors. The temporal inferior sector and the temporal superior sector were rightangled and were tilted 13° temporal to the vertical optic disc axis. The temporal horizontal sector and the nasal sector covered the remaining area. The shape of the optic disc was described by its horizontal, vertical, minimal, and maximal diameters and by the ratio of minimal-to-maximal disc diameter. The optic cup depth was scaled into degrees ranging from “0” for no cupping to “5” for very deep cupping. The diameters of the retinal arterioles were

measured at the optic disc border in the inferotemporal, superotemporal, superonasal, and inferonasal region. The method has already been described in detail.26 In addition, the patients included in the study underwent 24hour intraocular pressure profiles with measurements at 5 pm, 9 pm, midnight, 7 am, and noon. We recorded the five highest measurements and the five lowest measurements. In the descriptive analysis, we present means and standard deviations, as well as medians and ranges. For the comparison of eyes with hemorrhages and control eyes from the same patient, statistical tests for paired samples were applied. Depending on the skewness and the maximum absolute difference in the distribution function to the normal distribution, the t test (skewness between ⫺1 and ⫹1, maximum absolute difference 10%), the Wilcoxon test for paired samples (skewness between ⫺1 and ⫹1, maximum absolute difference ⬎ 10%), or the sign test (skewness less than ⫺1 or greater than ⫹1) was applied. The level of significance was 0.05 (two-sided) in all statistical tests. However, because this was an exploratory analysis on a great number of variables, no correction for multiple testing was applied. Therefore, P values and significances are of a descriptive nature. A power analysis is given in the results. This analysis was performed using the commercially available package nquery, release 3.1 (Elashoff JD (2000) Nquery advisor version 4.0 Users guide, Cork, IRL: Statistical Solutions Limited). The remaining statistical analyses were performed using the statistical software package SPSSWIN, release 9.0 (SPSS Inc., Chicago, IL).

Results The affected eyes compared with the contralateral unaffected eyes did not vary significantly (P ⬎ 0.20) in size and shape of the optic disc, area of the neuroretinal rim as a whole and measured separately in the four disc sectors, overall size, regional distribution of alpha zone and beta zone of parapapillary atrophy, and the diameter of the retinal arteries and veins at the optic disc border (Tables 1, 2). Correspondingly, refractive error, right eye or left eye, perimetric indices, and minimal and maximal intraocular pressure measurements did not differ significantly (P ⬎ 0.20) between the affected eye with disc bleeding and the contralateral eye without disc hemorrhage. Similar results were obtained if the entire study group was divided into subgroups of patients with primary open-angle glaucoma, patients with secondary open-angle glaucoma, and patients with normal-pressure glaucoma, respectively, in which the eyes with disc hemorrhage and the contralateral eyes without disc bleeding did not vary in the parameters measured (P ⬎ 0.40, P ⬎ 0.30, and P ⬎ 0.50, respectively).

Power Analysis Referring to the sample size of 198 eyes of 99 subjects, to a significance level of 0.05 (two-sided) and to a power of 80%, differences of approximately 0.3 standard deviations between eyes with and without hemorrhages would have been detectable using the t test for paired samples. Proportions of 0.36 respectively 0.64 of positive/negative differences between eyes with and without hemorrhages would have been detectable using the sign test.

Discussion The results suggest that, in patients with bilateral chronic open-angle glaucoma and unilateral optic disc hemorrhage,

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Ophthalmology Volume 109, Number 11, November 2002 Table 1. Data (Mean ⫾ Standard Deviation) of Eyes with Progression and Eyes with No Progression of Glaucoma

Optic disc area (mm2) Median Range Optic disc shape Vertical/horizontal Disc diameter Median Range Minimal/maximal Disc diameter Median Range Neuroretinal rim area Total (mm2) Median Range Temporal horizontal Median Range Temporal inferior Temporal inferior Median Range Temporal superior Median Range Nasal Median Range Optic cup depth (0–5) Median Parapapillary atrophy Alpha zone (mm2) Total Median Range Temporal horizontal Median Range Temporal inferior Median Range Temporal superior Median Range Nasal Median Range Beta zone (mm2) Total Median Range Temporal horizontal Median Range Temporal inferior Median Range Temporal superior Median Range Nasal Median Range

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Affected Eye with Disc Hemorrhage

Contralateral Eye without Disc Hemorrhage

2.81 ⫾ 0.64 2.72 1.68 ⫺ 4.92

2.76 ⫾ 0.62 2.62 1.42 ⫺ 5.00

1.05 ⫾ 0.10 1.05 0.79–1.39

1.06 ⫾ 0.09 1.05 0.81–1.31

0.88 ⫾ 0.06 0.89 0.55–0.97

0.88 ⫾ 0.05 0.89 0.73–0.98

0.98 ⫾ 0.42 0.95 0.12–2.11 0.21 ⫾ 0.13 0.19 0.00 ⫾ 0.60 0.23 ⫾ 0.13 0.23 ⫾ 0.13 0.23 0.00–0.57 0.24 ⫾ 0.12 0.24 0.04–0.75 0.32 ⫾ 0.19 0.31 0.02–0.75 2.88 ⫾ 0.73 3

0.97 ⫾ 0.46 0.97 0.09–2.59 0.19 ⫾ 0.12 0.17 0.00 ⫾ 0.54 0.25 ⫾ 0.14 0.25 ⫾ 0.14 0.25 0.00–0.66 0.24 ⫾ 0.13 0.23 0.00–0.63 0.32 ⫾ 0.17 0.32 0.03–0.84 2.74 ⫾ 0.82 3

0.80 ⫾ 0.76 0.69 0.00 ⫾ 4.67 0.29 ⫾ 0.24 0.28 0.00–1.29 0.19 ⫾ 0.20 0.15 0.00 ⫾ 1.04 0.18 ⫾ 0.19 0.12 0.00–1.02 0.14 ⫾ 0.26 0.00 0.00–1.32

0.91 ⫾ 0.91 0.77 0.00 ⫾ 4.21 0.33–0.31 0.31 0.00–1.80 0.19 ⫾ 0.22 0.13 0.00–0.99 0.19 ⫾ 0.21 0.13 0.00–1.14 0.19 ⫾ 0.34 0.00 0.00–1.96

0.88 ⫾ 0.99 0.62 0.00–5.66 0.24 ⫾ 0.30 0.16 0.00–1.72 0.25 ⫾ 0.36 0.14 0.00–1.86 0.14 ⫾ 0.05 0.05 0.00–0.87 0.18 ⫾ 0.43 0.00 0.00–2.76

0.78 ⫾ 0.97 0.46 0.00–4.70 0.21 ⫾ 0.26 0.12 0.00–1.06 0.22 ⫾ 0.32 0.07 0.00–1.43 0.15 ⫾ 0.25 0.03 0.00–1.36 0.29 ⫾ 0.53 0.00 0.00–3.86 (continued)

Jonas et al 䡠 Inter-eye Differences in Unilateral Glaucomatous Disc Hemorrhages Table 1. (continued) Data (Mean ⫾ Standard Deviation) of Eyes with Progression and Eyes with No Progression of Glaucoma

Retinal vessels Arteries Temporal inferior Temporal superior Nasal superior Nasal inferior Veins Temporal inferior Temporal superior Nasal superior Nasal inferior Intraocular pressure Maximal values

Minimal values

Refractive error Right eyes/Left eyes Perimetric indices Mean defect Loss variance

Affected Eye with Disc Hemorrhage

Contralateral Eye without Disc Hemorrhage

0.092 ⫾ 0.031 0.087 ⫾ 0.035 0.083 ⫾ 0.030 0.084 ⫾ 0.026

0.099 ⫾ 0.020 0.094 ⫾ 0.030 0.083 ⫾ 0.021 0.085 ⫾ 0.027

0.131 ⫾ 0.038 0.126 ⫾ 0.043 0.103 ⫾ 0.034 0.106 ⫾ 0.036

0.135 ⫾ 0.038 0.132 ⫾ 0.039 0.105 ⫾ 0.031 0.105 ⫾ 0.045

21.53 ⫾ 5.38 19.10 ⫾ 4.90 18.15 ⫾ 4.69 17.30 ⫾ 4.45 16.64 ⫾ 4.54 12.24 ⫾ 2.97 13.30 ⫾ 3.03 13.83 ⫾ 2.74 14.56 ⫾ 3.06 15.10 ⫾ 3.28 ⫺0.43 ⫾ 1.96 55/44 7.08 ⫾ 5.67 37.12 ⫾ 34.87

the affected eyes with the disc bleeding and the contralateral eyes without detected disc hemorrhages at the time of examination do not markedly differ in the appearance of the optic nerve head or in refractive error, intraocular pressure measurements, and visual field loss. It may suggest that the development of optic disc hemorrhages in patients with bilateral chronic open-angle glaucoma and unilateral optic disc hemorrhage does not markedly depend on inter-eye differences in size and shape of the optic disc, neuroretinal rim and parapapillary atrophy, diameter of the retinal vessels, intraocular pressure measurements, and visual field loss. It may also hold true for subgroups of patients with primary open-angle glaucoma, secondary chronic open-angle glaucoma, and normal-pressure glaucoma, because the results did not vary significantly between the three types of glaucoma included in this study. If one takes into account that flame-shaped hemorrhages at the optic disc border, in the absence of a hemorrhagic retinopathy, are strongly connected with glaucomatous optic neuropathy, and if one assumes that disc hemorrhages are indicative for progression of glaucomatous optic nerve damage, one may suggest that the mechanism leading to the unilaterally observed disc hemorrhage may be present in both eyes of the same individual and that it leads to a disc bleeding ophthalmoscopically detected just in one eye at the time of examination. In view of the association of disc hemorrhages with progression of glaucomatous optic nerve damage, one may consequently infer that, clinically, in patients with bilateral open-angle glaucoma and unilateral disc hemorrhage, both eyes need a more intensive antiglau-

20.94 ⫾ 5.48 18.65 ⫾ 4.05 17.81 ⫾ 4.02 16.87 ⫾ 3.33 16.18 ⫾ 3.60 12.08 ⫾ 2.84 13.25 ⫾ 2.63 13.63 ⫾ 2.46 14.46 ⫾ 2.93 14.91 ⫾ 3.33 ⫺0.47 ⫾ 2.05 45/54 7.26 ⫾ 6.22 34.16 ⫾ 34.87

comatous treatment to prevent progression of glaucomatous optic nerve damage in both eyes. There are limitations to the study. Because of the study composition, only white patients were included, so that the results may primarily be valid only for white patients with bilateral chronic open-angle glaucoma. Because inter-eye differences were evaluated, the results cannot be interpreted in a manner that the development of disc hemorrhages is or is not dependent on the appearance of the optic nerve head, intraocular pressure, or degree of visual field loss in general. The inter-eye differences in the study were not markedly large, so that a clinical significance might have been hidden in a statistical nonsignificance. The statistical power analysis revealed, however, that at the given sample size and a significance level of 0.05, inter-eye differences of approximately 0.3 standard deviations and proportions of 0.36 respectively 0.64 of positive/negative inter-eye differences would have been detected. Another limitation of the study is that the contralateral eye without detected disc hemorrhage at the time of inclusion into this study may have developed optic disc bleeding before inclusion into the study, or it may have shown an optic disc hemorrhage some time later than the time when the optic disc photograph was taken. This limitation of the study may, however, only serve to underline the conclusion that in a patient in whom a unilateral optic disc hemorrhage is detected, the antiglaucomatous treatment may be intensified for both eyes. In conclusion, in patients with bilateral chronic openangle glaucoma, the occurrence of detected optic disc hemorrhages is not associated with marked side differences in

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Ophthalmology Volume 109, Number 11, November 2002 Table 2. Pairwise Comparison between Eyes with or without Optic Disc Hemorrhages. Name

Difference

Standard Deviation

ⴞ

Skewness

KolmogorovSmirnov

Test

P Value

Optic disc area Vertical/horizontal disc diameter Minimal/maximal disc diameter Rim area, total Rim area, temporal Rim area, superior temporal Rim area, inferior temporal Rim area, nasal Optic cup depth Alpha zone, total Alpha zone, temporal Alpha zone, inferior temporal Alpha zone, superior temporal Alpha zone, nasal Beta zone, total Beta zone, temporal Beta zone, inferior temporal Beta zone, superior temporal Beta zone, nasal Artery diameter inferior temporal Artery diameter superior temporal Artery diameter, superior nasal Artery diameter, inferior nasal Vein diameter, inferior temporal Vein diameter, superior temporal Vein diameter, superior nasal Vein diameter, inferior nasal IOP, maximal value 1 IOP, maximal value 2 IOP, maximal value 3 IOP, maximal value 4 IOP, maximal value 5 IOP, minimal value 1 IOP, minimal value 2 IOP, minimal value 3 IOP, minimal value 4 IOP, minimal value 5 Refractive error Mean perimetric loss Perimetric loss variance

0.047 ⫺0.0069 ⫺0.022 0.014 0.027 0.0015 ⫺0.016 0.0015 0.096 ⫺0.13 ⫺0.038 ⫺0.0037 ⫺0.015 ⫺0.057 0.094 0.034 0.029 ⫺0.0029 ⫺0.021 ⫺0.029

0.48 0.085 0.071 0.42 0.11 0.12 0.15 0.16 0.63 0.76 0.26 0.22 0.18 0.34 0.78 0.25 0.28 0.24 0.51 0.30

50/49 47/52 54/44 47/51 52/35 51/44 42/50 48/43 12/8 34/41 35/44 40/40 37/42 21/28 44/32 46/27 45/31 38/28 25/16 44/47

⫺0.4 ⫺1.3 ⫺2.6 ⫺0.1 0.9 ⫺0.6 0.1 0.2 1.0 ⫺0.9 ⫺0.3 ⫺1.0 ⫺0.7 ⫺0.8 ⫺0.05 0.1 ⫺1.0 ⫺1.6 ⫺3.4 ⫺9.0

9 10 16 7 15 7 6 8 40 13 11 14 16 27 15 17 14 22 35 41

t-test Sign Sign t-test Wilcoxon t-test t-test t-test Wilcoxon Wilcoxon Wilcoxon Wilcoxon Wilcoxon Wilcoxon Wilcoxon Wilcoxon Wilcoxon Sign Sign Sign

0.33 0.69 0.36 0.73 0.050 0.90 0.29 0.93 0.18 0.22 0.16 0.71 0.58 0.12 0.11 0.14 0.11 0.27 0.21 0.83

⫺0.0053

0.039

43/49

⫺0.3

10

t-test

0.20

⫺0.029 0.030 ⫺0.042 ⫺0.0072 0.0010 ⫺0.017 0.65 0.53 0.39 0.48 0.51 0.22 0.11 0.22 0.16 0.24 0.048 ⫺0.059 3.63

0.29 0.28 0.41 0.18 0.051 0.17 4.8 4.0 3.8 3.4 3.3 2.1 2.6 2.3 2.4 2.5 0.49 11.6 36.4

37/27 34/34 48/46 47/47 31/35 34/35 31/19 25/24 21/29 24/24 26/21 24/24 22/27 24/19 28/27 30/25 20/11 36/37 38/32

⫺7.5 7.1 ⫺9.4 1.6 ⫺0.4 ⫺6.9 2.4 5.3 5.2 4.7 4.0 3.6 2.8 3.6 2.5 2.0 ⫺0.2 ⫺0.9 ⫺0.2

41 39 41 29 15 29 23 27 27 25 27 25 24 23 17 16 35 20 19

Sign Sign Sign Sign Wilcoxon Sign Sign Sign Sign Sign Sign Sign Sign Sign Sign Sign Wilcoxon Wilcoxon Wilcoxon

0.26 1.0 0.92 1.0 0.98 1.0 0.12 1.0 0.32 1.0 0.56 1.0 0.57 0.54 1.0 0.59 0.22 0.93 0.52

IOP ⫽ Intraocular pressure. The fourth column with the ⫾ description gives the number of eyes with a disc hemorrhage, in which the value of the parameter was larger (“⫹”) or smaller (“⫺”) than in the contralateral eyes without disc bleeding. The fifth column gives the skewness. If the value was larger than ⫹1 or smaller than ⫺1, the sign test was applied. The sixth column (“K-S”) gives the Kolmogorov-Smirnov test with the maximal absolute deviation from the normal distribution function. If the skewness was between ⫺1 and ⫹1, and if the deviation from the normal distribution was larger than 10%, the Wilcoxon Test was applied. If the skewness was between ⫺1 and ⫹1, and if the deviation from the normal distribution curve was equal to or less than 10%, the t test was used. The seventh column describes the test that was used, according to the results given in the fifth and sixth columns.

the morphology of the optic nerve head such as size of the optic disc and neuroretinal rim and occurrence of parapapillary atrophy. It may suggest that the mechanism leading to disc hemorrhages is equally distributed or effective in both eyes of patients with bilateral chronic open-angle glaucoma, independently of whether it is primary open-angle glaucoma, secondary chronic open-angle glaucoma, or normalpressure glaucoma. It may suggest that in a patient in whom a unilateral optic disc hemorrhage is detected, the chance of the contralateral eye to develop an optic disc bleeding may be as high as the chance was for the affected eye to develop an optic disc bleeding. Because such a hemorrhage may be

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a sign of progression of glaucoma, both eyes of patients with unilateral optic disc hemorrhage should get intensive antiglaucomatous treatment.

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