Iris colour, optic disc dimensions, degree and progression of glaucomatous optic nerve damage

PURPOSE: To evaluate whether iris colour influences size and shape of the optic nerve head and risk for glaucoma progression. METHODS: The hospital-based observational study included 1973 eyes of 1012 Caucasian subjects with ocular hypertension or chronic open-angle glaucoma. For all patients, colour stereo optic disc photographs were evaluated, and corneal pachymetry and achromatic perimetry were performed. Main outcome measures were optic nerve head parameters, the development or progression of visual field defects and iris colour. RESULTS: In most of the study groups, size of the optic disc, neuroretinal rim, alpha zone and beta zone of parapapillary atrophy, retinal vessel diameter and central corneal thickness did not differ significantly between eyes with blue, green, brown and mixed iris colour. In the normal-pressure glaucoma group, neuroretinal rim area was smallest in the population with mixed-coloured eyes and largest in the group of eyes with brown irides (P = 0.001 after correction for inter-eye dependency and multiple testing). For the ocular hypertensive subjects and glaucoma patients with follow-up examinations, the rate of development or progression of glaucomatous visual field loss was not significantly associated with iris colour (P = 0.060). CONCLUSIONS: In Caucasian subjects, iris colour does not have a major association with the size of the optic nerve head structures, central corneal thickness and retinal arterial diameter. In Caucasian patients with ocular hypertension or chronic open-angle glaucoma, an influence of iris colour on the risk for development or progression of glaucomatous visual field defects could not be confirmed.     

Optic disc area in different types of glaucoma

AIM: To evaluate the possible relationship of optic disc area with retina nerve fiber layer in different glaucoma subtypes. METHODS: One eye each was chosen from 45 patients with ocular hypertension, 45 patients with primary open angle glaucoma, 45 patients with pseudoexfoliation glaucoma and 45 healthy controls followed in our hospital. The records of the patients were reviewed retrospectively. Optic disc area and circumpapillary retina nerve fiber layer measurements were obtained using optical coherence tomography. Central corneal thickness was measured by ultrasound pachymetry. RESULTS: The median disc area in the patients with primary open angle glaucoma was significantly higher than the patients with ocular hypertension (2.19 vs 1.90 mm2, P=0.030). The median retina nerve fiber layer was thinner in the patients with primary open angle glaucoma and pseudoexfoliation glaucoma than the patients with ocular hypertension for superior, inferior and temporal quadrants. After adjustment for age, no difference in central corneal thickness was found between the groups. Greater disc area was associated with thicker retinal nerve fiber layer for superior, inferior and nasal quadrants in the patients with primary open angle glaucoma. There was no correlation between disc area and central corneal thickness measurements of the groups. CONCLUSION: Disc size affects the retinal nerve fiber layer thickness in eyes with primary open angle glaucoma and is a possible risk factor for glaucomatous optic nerve damage.     

Central corneal thickness in low-tension glaucoma

BACKGROUND: It is possible that the intraocular pressure (IOP) is underestimated in eyes whose central cornea is thinner than normal. The objective of this study was to determine and establish the significance of central corneal thickness in patients with low-tension (normal-tension) glaucoma compared with those with chronic open-angle glaucoma (COAG) or ocular hypertension and healthy eyes. METHODS: The study was carried out from February 1998 to May 1999. Central corneal thickness was measured by ultrasonic pachymetry and IOP was measured by Goldmann applanation tonometry in 25 patients with low-tension glaucoma (untreated IOP less than 21 mm Hg with evidence of optic nerve head damage and corresponding visual field loss on automated perimetry), 80 patients with COAG (untreated IOP 21 mm Hg or greater with evidence of optic nerve head damage and corresponding visual field loss on automated perimetry), 16 patients with ocular hypertension (untreated IOP 21 mm Hg or greater, with normal optic nerve head and no history of glaucoma or elevated IOP, and normal visual field on automated perimetry) and 50 control subjects (untreated IOP less than 21 mm Hg with normal optic nerve head and no history of glaucoma or elevated IOP). Analysis with Pearson's product-moment correlation was performed to determine the correlation of IOP and central corneal thickness, and one-way analysis of variance was used to compare corneal thickness between groups. RESULTS: The central cornea was significantly thinner in the low-tension glaucoma group (mean 513.2 mu [standard deviation (SD) 26.1 mu]) than in the COAG group (mean 548.2 mu [SD 35.0 mu]) and the control group (mean 556.7 mu [SD 35.9 mu]) (p < 0.001). No significant difference in corneal thickness was found between the COAG and control groups. The ocular hypertension group had significantly thicker corneas (mean 597.5 mu [SD 23.6 mu]) than the three other groups (p < 0.001). INTERPRETATION: Patients with low-tension glaucoma may have thinner corneas than patients with COAG and healthy subjects. This results in underestimation of their IOP. Corneal thickness should be taken into account when managing these patients to avoid undertreatment.     

Keratometry, optic disc dimensions, and degree and progression of glaucomatous optic nerve damage

PURPOSE: To evaluate whether keratometric readings as a measure of corneal shape are associated with optic disc dimensions and with the degree and rate of perimetric progression of chronic open-angle glaucoma or ocular hypertension. METHODS: The hospital-based observational study included 1826 eyes of 936 patients with ocular hypertension, patients with chronic open-angle glaucoma, or normal individuals. For 733 ocular hypertensive or glaucomatous eyes, follow-up examinations were performed with a mean follow-up time of 58.0+/-34.7 months. Observation procedures were keratometry, morphometric optic disc analysis, tonometry, and perimetry. RESULTS: In the normal study group, area of the neuroretinal rim, alpha zone and beta zone of parapapillary atrophy, and retinal vessel diameter were not significantly associated with keratometric readings. In the entire study population, the optic disc area was significantly (P<0.001; r=-0.27) correlated with low keratometric readings as expressed in diopters. Keratometric readings were significantly (P<0.001 adjusted for age, intraocular pressure, baseline damage, and corneal asphericity) smaller in the normal-pressure glaucoma group than in the normal study group and in the groups with ocular hypertension or primary and secondary open-angle glaucoma. Rate of perimetric progression was not significantly associated with low keratometric readings, either in simple or in multiple Cox regression analysis, controlling for baseline damage, ocular hypertension, age, corneal asphericity, and intraocular pressure. CONCLUSIONS: Large optic disc area is statistically significantly, but clinically weakly, correlated with low keratometric readings (diopters). In Caucasian individuals with ocular hypertension and patients with chronic open-angle glaucoma, the rate of development or progression of glaucomatous visual field defects is not significantly associated with keratometric readings.     

Predictive factors of the optic nerve head for development or progression of glaucomatous visual field loss

PURPOSE: To evaluate which morphologic features of the optic disc are predictive factors for the development or progression of visual field loss in chronic open-angle glaucoma. METHODS: The prospective observational clinical study included 763 eyes of 416 white subjects with ocular hypertension and chronic open-angle glaucoma. During the follow-up time (mean, 67.4 months; median, 65.1; range, 6.2-104.5), all patients underwent repeated qualitative and morphometric evaluation of color stereo optic disc photographs and white-on-white visual field examination. Progression of glaucomatous visual field damage was defined by point-wise regression analysis for each of the 59 locations in the visual field. Outcome measures were qualitative and quantitative morphologic optic nerve head parameters. RESULTS: Development or progression of glaucomatous visual field defects was detected in 106 (13.9%) eyes. At baseline of the study, neuroretinal rim area was significantly (P < 0.002) smaller, the beta zone of parapapillary atrophy (P < 0.003, nasal sector) was significantly larger, and age was significantly higher (P < 0.003) in the progressive study group than in the nonprogressive study group. Both study groups did not vary significantly in size of the optic disc and the alpha zone of parapapillary atrophy. Cox proportional hazard regression analysis revealed that the progression of glaucomatous visual field loss depended significantly on the area of the neuroretinal rim (P < 0.001) and age (P < 0.001), but was independent of diameter of the retinal arterioles and veins. CONCLUSIONS: Morphologic predictive factors for development or progression of glaucomatous visual field defects in whites are small neuroretinal rim area and large beta zone of parapapillary atrophy. Age is an additional nonmorphologic parameter. Progression of glaucomatous optic nerve head changes is independent of the size of the optic disc and alpha-zone of parapapillary atrophy and retinal vessel diameter.     

应用SD-OCT纵向比较正常人群和青光眼进展及非进展人群的RNFL厚度

目的：应用频域光学相干断层扫描（ spectral－domain optical coherence tomography ,SD－OCT）纵向比较正常人群、青光眼进展及非进展人群的视网膜神经纤维层（ retinal nerve fiber layer ,RNFL）厚度。方法：应用SD－OCT对36例POAG患者和24例正常人监测RNFL厚度。受试者行视盘OCT、眼底照相及视野检查,每6mo一次,随访2a,至少有4次可信的OCT检查结果。根据视野及眼底照相结果将POAG患者划分为进展组和非进展组。分析各组RNFL厚度变化差异,同视野参数变化值做相关性分析。结果：平均随访2．1±0．3 a。17例被确定为POAG进展组。POAG进展组平均RNFL厚度损失速率明显高于POAG非进展组（2．46μm／a vs 1．21μm／a,P＜0．001）。下方RNFL厚度变化同视野平均偏差（ mean deviation ,MD）变化相关性最佳（r＝0．423,P＝0．03）。结论：应用SD－OCT纵向监测RNFL厚度, POAG进展者RNFL厚度丢失速率明显增高,下方RNFL厚度参数变化可能在监测中意义较大。     

Comparison of optical coherence tomography and scanning laser polarimetry in glaucoma, ocular hypertension, and suspected glaucoma.

BACKGROUND AND OBJECTIVE: To compare the performance of the newest generation optical coherence topography (OCT) and scanning laser polarimetry with variable corneal compensation (SLP-VCC) in eyes with glaucoma, ocular hypertension, and suspected glaucoma. PATIENTS AND METHODS: One eye each of 84 patients (30 with glaucoma, 26 with suspected glaucoma, and 28 with ocular hypertension) was included in the study. Retinal nerve fiber layer (RNFL) thickness was measured with both technologies and thickness parameters were compared in the three groups of eyes. The correspondence of RNFL thickness measurements with visual field function was also studied. RESULTS: Average OCT-RNFL thickness was found to have a statistically significant difference between patients with glaucoma and either suspected glaucoma or ocular hypertension. A statistically significant correlation between the average RNFL thicknesses measured by the two different technologies was shown only in the glaucoma group. A significant correlation with visual field mean deviation was found for superior average RNFL thickness as measured by SLP and for nerve fiber indicator and average and inferior average RNFL thickness as measured by OCT in glaucomatous eyes. Regression analysis indicated nerve fiber indicator to be the most valuable factor in predicting mean deviation. CONCLUSION: RNFL thickness measurements obtained with OCT and SLP-VCC correlate well only in eyes with more advanced glaucomatous damage. The nerve fiber indicator parameter derived by SLP correlated best with mean deviation.     

Corneal thickness measurements and visual function abnormalities in ocular hypertensive patients

PURPOSE: It has been suggested that a considerable subset of patients currently classified as having ocular hypertension may have thicker than average corneas that result in an overestimation of the true intraocular pressure (IOP). As a consequence, ocular hypertension patients with greater corneal thickness may be at a lower risk for functional damage, such as that detected by short-wavelength automated perimetry (SWAP). The purpose of this study was to evaluate the frequency of SWAP deficits in ocular hypertension patients and to correlate these findings with corneal thickness measurements in the same patients. DESIGN: Cross-sectional observational study. METHODS: Sixty-eight ocular hypertension patients with normal optic disks and 63 normal subjects were included in the study. All participants underwent standard automated perimetry (SAP), SWAP, and central corneal thickness measurements using ultrasound pachymeter. Central corneal thickness measurements in ocular hypertension patients with abnormal visual field test results were compared with central corneal thickness measurements in ocular hypertension patients with normal visual field results. In addition, central corneal thickness measurements in ocular hypertension patients were compared with central corneal thickness measurements in normal subjects. RESULTS: Sixteen of 68 patients with ocular hypertension (24%) demonstrated SWAP abnormalities, whereas four of 68 (6%) showed a deficit on SAP. The mean central corneal thickness in ocular hypertension patients with abnormal SWAP results was significantly lower than the mean central corneal thickness in ocular hypertension patients with normal SWAP results (545 +/- 25 microm vs 572 +/- 35 microm; P =.006). The mean central corneal thickness in the normal group was 557 +/- 33 microm. The mean central corneal thickness in ocular hypertension patients with normal SWAP results was significantly higher than in normal subjects (P =.02). There was no significant difference between mean central corneal thickness in normal subjects and in ocular hypertension patients with abnormal SWAP results (P =.19). CONCLUSIONS: The patients classified as having ocular hypertension but with visual field loss detected by SWAP had significantly lower central corneal thickness measurements than the ocular hypertension patients with normal visual field results. These results suggest that central corneal thickness should be taken into account when assessing risk for the development of glaucomatous damage among ocular hypertension patients.     

Corneal thickness in congenital glaucoma

PURPOSE: To compare central corneal thickness between eyes with congenital glaucoma and normal controls and to correlate this parameter with corneal diameter and axial length. METHODS: Eyes of consecutive children with congenital glaucoma with previous glaucoma surgery and eyes of children with inadequacy of lacrimal drainage system with age less than 3 years old were examined under inhalatory general anesthesia. Complete ophthalmologic examination, central corneal thickness, axial length, and corneal diameter measurements were performed. All patients presented with intraocular pressure (IOP) less than 21 mm Hg and no clinical sign of corneal edema. RESULTS: Fifty-five eyes of 55 patients (30 congenital glaucoma and 25 controls) were examined (mean age = 16.6 +/- 10.6 months; 20 female/ 35 males). There was no significant difference in age and gender between glaucoma patients and normal subjects. Mean IOP was higher in glaucomatous eyes (P = 0.02). Corneal diameter and axial length between glaucomatous eyes and controls were significantly different (P < 0.0001 for both). Central corneal thickness was significantly thinner in glaucomatous eyes (P = 0.01). There was a significant correlation between corneal diameter and central corneal thickness and also between central corneal thickness and axial length (r2 = 0.32 and r2 = 0.18, respectively; P < 0.0001 for both). CONCLUSION: Central corneal thickness was significantly thinner in children with congenital glaucoma. This finding may be another confounding factor when measuring IOP in those patients. Pachymetry should be considered during their examination.     

Preperimetric glaucoma diagnosis by confocal scanning laser tomography of the optic disc

AIM: To evaluate the ability of confocal scanning laser tomography of the optic nerve head to detect glaucomatous optic nerve damage in ocular hypertensive eyes without visual field defects. METHODS: The study included 50 normal subjects, 61 glaucoma patients with glaucomatous changes in the optic disc and visual field, and 102 "preperimetric" patients with increased intraocular pressure, normal visual fields, and glaucomatous appearance of the optic disc as evaluated on colour stereo optic disc photographs. For all individuals, confocal scanning laser tomographs of the optic nerve head were taken using the Heidelberg retina tomograph (HRT; software 2.01). RESULTS: Almost all investigated HRT variables varied significantly (p < 0.05) between the normal eyes and preperimetric glaucoma eyes with pronounced overlap between the two study groups. Corresponding to the overlap, sensitivity and specificity values were relatively low when HRT variables were taken to differentiate between normal and preperimetric glaucoma eyes. At a given specificity of 95% highest sensitivities were found for the variables "rim area in the superior disc sector" (24.8%), "nerve fibre layer thickness in the inferior disc sector" (26.5%), and "rim volume in the superior disc sector" (25.5%). A multivariate approach increased sensitivity to 42.2% at a given specificity of 95%. For the glaucoma group highest sensitivity values were reached by rim volume in the superior disc sector (73.8%) and rim area (72.1%); the multivariate approach reached 83.6%. CONCLUSIONS: Owing to pronounced overlapping between the groups, confocal scanning laser tomography of the optic nerve head has relatively low diagnostic power to differentiate between normal eyes and preperimetric glaucoma eyes. One of the reasons may be the biological interindividual variability of quantitative optic disc variables.     

Polarimetric measurement of retinal nerve fiber layer thickness in glaucoma diagnosis

PURPOSE: To evaluate reliability and diagnostic value of polarimetric measurements of the retinal nerve fiber layer (RNFL) thickness in the diagnosis of glaucoma. METHODS: The study included 81 eyes with perimetric glaucoma with glaucomatous changes of the optic disc and visual field defects; 52 eyes with preperimetric glaucoma with glaucomatous optic disc abnormalities and normal achromatic visual fields; and 70 normal eyes. For determination of reliability, four examiners repeated polarimetric measurements five times in ten normal subjects. RESULTS: The polarimetric variables were significantly correlated with increasing mean visual field defect and decreasing neuroretinal rim area. In correlation analyses with visual field defects, correlation coefficients were highest for the variable "superior/nasal ratio" and "the Number," a variable calculated by the neural network of the device. In correlations with neuroretinal rim area, correlation coefficients were highest for measurements of the inferior nerve fiber layer thickness. The preperimetric glaucoma group and the control group differed significantly in the variables "superior/nasal ratio" and "the Number" and, to a smaller degree, in the variables "superior/temporal ratio" and "superior/inferior ratio." The Number variable had a sensitivity of 82% and 58% at a predefined specificity of 80% in separating perimetric glaucoma patients and preperimetric glaucoma patients, respectively, from control subjects. Reproducibility of the polarimetric measurements ranged between 70% and 89%. CONCLUSION: Polarimetric measurements of the RNFL thickness can detect glaucomatous optic nerve damage in patients with visual field loss, and in some patients with preperimetric glaucomatous optic nerve damage. Considering the fast performance, easy handling, and low maintenance costs, RNFL polarimetry may be helpful in glaucoma diagnosis.     

Monitoring glaucoma progression with visual evoked potentials of the blue-sensitive pathway

PURPOSE: To determine the value of visual evoked potentials with blue-on-yellow pattern stimulation in follow-up of glaucoma. METHODS: This prospective longitudinal concurrent study included a heterogeneous cohort of two groups, perimetric (n = 161) and preperimetric (n = 118), of patients with chronic open-angle glaucoma and 113 healthy control subjects. In the preperimetric glaucoma group, patients showed glaucomatous abnormalities of the optic disc, maximum intraocular pressure higher than 21 mm Hg, and unremarkable computerized visual field examination results. Patients underwent up to three VEP measurements with blue-on-yellow pattern stimulation, as well as qualitative and morphometric evaluation of color stereo optic disc photographs. Mean follow-up time between measurements was 24 months. VEP measurements were separately analyzed in preperimetric subjects, with and without progression of optic nerve damage. Progression of glaucoma was defined as increasing loss of neuroretinal rim. RESULTS: A separate analysis of VEP peak times in patients in the preperimetric group, with and without progression of glaucomatous optic nerve damage, showed no significant difference at baseline but a significant prolongation (P = 0.01) in patients with progressive disease, 2 years before morphologic changes were evident. VEPs in patients with nonprogressive disease were statistically unchanged during the observation period. The perimetric group and both preperimetric groups showed significantly prolonged VEP peak times in comparison with the control group (P < 0.001). CONCLUSIONS: In addition to photographic evaluation to detect glaucomatous disc atrophy, the blue-on-yellow VEP may be an objective electrophysiological tool for monitoring patients with glaucoma, because peak times are significantly associated with progression of optic nerve damage.     

Central corneal thickness and thickness of the lamina cribrosa in human eyes

PURPOSE: Since central corneal thickness may inversely influence the amount and rate of progression of glaucomatous optic nerve damage and because lamina cribrosa thickness may be of importance in susceptibility to glaucoma, it was the purpose of the present study to evaluate whether central corneal thickness is related to lamina cribrosa thickness. METHODS: The histomorphometric study included 111 enucleated nonglaucomatous eyes of 111 white subjects. On anterior-posterior histologic sections through the pupil and the central optic disc region, the thickness of the cornea, lamina cribrosa, and peripapillary sclera and the shortest distance between the intraocular space and the cerebrospinal fluid space were measured. Axial length ranged between 20 and 32 mm. RESULTS: Mean central corneal thickness (mean +/- SD: 616.6 +/- 108.3 microm) and mean central lamina cribrosa thickness (378.1 +/- 117.8 microm) were statistically independent of each other (P = 0.15; correlation coefficient, r = 0.14). In a similar manner, lamina cribrosa thickness at the optic disc border was statistically independent of central corneal thickness (P = 0.51; r = 0.06) and peripheral corneal thickness (P = 0.34; r = 0.09). In a parallel way, peripapillary scleral thickness (P = 0.84) and the shortest distance between the prelaminar space and cerebrospinal fluid space (P = 0.10) were statistically independent of central corneal thickness. CONCLUSIONS: In nonglaucomatous human globes, central corneal thickness may not correlate significantly with lamina cribrosa thickness, peripapillary scleral thickness, and shortest distance between intraocular space and cerebrospinal fluid space. Histologic artifact and sectioning methods could partially account for the lack of an association. The study results may suggest clinically that an assumed relationship between central corneal thickness and susceptibility to glaucoma cannot be explained by an anatomic correspondence between corneal thickness and histomorphometry of the optic nerve head.     

Evaluation of the glaucomatous damage on retinal nerve fiber layer thickness measured by optical coherence tomography

PURPOSE: To evaluate the relationship between visual field and retinal nerve fiber layer (RNFL) thickness measured by optical coherent tomography (OCT) and to assess the diagnostic ability of OCT to distinguish between early glaucomatous or glaucoma-suspect eyes from normal eyes. DESIGN: Retrospective, non-randomized, cross-sectional study. METHODS: A total of 160 eyes of 120 normal Japanese adults, 23 eyes of 16 patients with ocular hypertension, 38 eyes of 35 glaucoma-suspect patients, and 237 glaucomatous eyes of 140 glaucoma patients were enrolled in the study. The glaucoma group included 89 early glaucomatous eyes. Thickness of the RNFL around the optic disk was determined with three 3.4-mm diameter circle OCT scans. Average and segmental RNFL thickness values were compared among all groups. The correlation between mean deviation and RNFL thickness in glaucomatous eyes was also analyzed. Receiver operating characteristic (ROC) curve area was calculated to discriminate normal eyes from early glaucomatous or glaucoma-suspect eyes. RESULTS: A significant relationship existed between the mean deviation and RNFL thickness in all parameters excluding the 3-o'clock area. The average RNFL thickness had the strongest correlation in all parameters (r = -0.729, P <.001). Retinal nerve fiber layer thickness at the 7-o'clock inferotemporal segment had the widest areas under the ROC curves in all parameters for early glaucomatous eyes (0.873). CONCLUSIONS: Measurement of RNFL thickness by OCT is useful in detecting early RNFL damage. Furthermore, OCT measurements of RNFL thickness may provide clinically relevant information in monitoring glaucomatous changes.     

Correlation between intraocular pressure control and progressive glaucomatous damage in primary open-angle glaucoma

Fifty-five patients with primary open-angle glaucoma and early glaucomatous damage who had medical therapy and laser trabeculoplasty were followed up for four to 11 years or until progressive glaucomatous damage was documented. Factors associated with the stability or progression of glaucoma were evaluated. Eyes with mean intraocular pressure higher than 21 mm Hg during the follow-up period uniformly had progressive glaucomatous changes. Conversely, eyes with mean intraocular pressure less than 17 mm Hg remained stable, and approximately half of the eyes with mean intraocular pressure between 17 and 21 mm Hg had progressive glaucomatous changes. Patients who remained stable were slightly younger than those with progressive glaucomatous changes (P less than .05), but initial optic nerve head appearance, initial visual field findings, number of medicines used, medical history, and patient gender or race were not statistically associated with stability or progression of the glaucoma. These findings reinforce the importance of intraocular pressure control in primary open-angle glaucoma and the need to identify other markers that help determine the proper level of intraocular pressure for individual patients.     

Corneal thickness and axial length

PURPOSE: A thin central cornea has been reported to be a risk factor for developing primary open-angle glaucoma among ocular hypertensive eyes. A thin scleral bed of lamina cribrosa seen in deeply excavated optic nerves in glaucomatous eyes is a quintessential finding in advanced glaucomatous eyes. Association between thin cornea and weak sclera contributing to vulnerability of lamina cribrosa has been postulated. The purpose of this study is to determine whether there is an association between corneal thickness and axial length of human eyes in a clinical setting. DESIGN: This is an observational, retrospective cross-sectional study. METHODS: The ocular parameters of 1,084 consecutive eyes with both corneal thickness and axial length measurements were analyzed and compared by age, gender, and race. RESULTS: In the total patient study group, there was no statistically significant association between central corneal thickness and axial length. Subgroup analysis by age, gender, and race also failed to show an association. CONCLUSIONS: Central corneal thickness and axial length are independent occurrences. Thin corneas are not associated with longer eyes.     

Central corneal thickness and development of glaucomatous optic disk hemorrhages

PURPOSE: To evaluate whether central corneal thickness influences the development of optic disk hemorrhages in chronic open-angle glaucoma. DESIGN: Prospective observational clinical study. METHODS: The study included 390 eyes of 223 white subjects with chronic open-angle glaucoma observed during a mean follow-up time of 61.3 +/- 36.4 months. Central corneal thickness was measured by corneal pachymetry. RESULTS: The event of optic disk hemorrhages during follow-up was detected in 63 eyes (16.2%). Development of optic disk hemorrhages was, univariately (P = .73) as well as in a multiple Cox regression analysis, controlling for age, sex, normal tension glaucoma, intraocular pressure, neuroretinal rim area, and size of beta zone of peripapillary atrophy, statistically independent (P = .56) of central corneal thickness. CONCLUSIONS: Development of optic disk hemorrhages may not be markedly influenced by central corneal thickness.     

Follow up of focal narrowing of retinal arterioles in glaucoma

AIM: To evaluate whether focal narrowing of retinal arterioles increases with progressive glaucomatous optic neuropathy. METHODS: Focal narrowing of retinal arterioles and area of neuroretinal rim were morphometrically evaluated on colour stereo optic disc photographs of 59 patients with primary open angle glaucoma, 22 patients with normal pressure glaucoma, 11 patients with secondary open angle glaucoma, and 31 patients with ocular hypertension. Minimum follow up was 8 months. Focal arteriolar narrowing was quantified by calculating the ratio of the vessel width in the broadest to the narrowest vessel part. RESULTS: In the subgroup of patients with progressive glaucomatous optic nerve damage (n = 37), focal narrowing of retinal arterioles increased significantly (p < 0.005) with decreasing neuroretinal rim area. In the subgroup of patients with stable appearance of the optic disc (n = 86), focal narrowing of retinal arterioles did not change significantly (p = 0.79). The positive correlation between increasing focal thinning of retinal arterioles and progression of glaucomatous optic neuropathy was present, although not statistically significant, in all the glaucoma subtypes examined. The location of focal thinning of retinal arterioles did not change in the follow up. CONCLUSIONS: Focal narrowing of retinal arterioles increases significantly with progressive glaucomatous optic neuropathy, independent of the type of glaucoma. It is stable in patients with non-progressive glaucoma. The findings agree with previous reports on a higher degree of focal arteriole narrowing in eyes with pronounced optic nerve damage in comparison with those with moderate optic nerve atrophy or normal eyes. In the clinical management of patients with glaucoma, in some eyes, increasing focal arteriole narrowing may suggest progression of disease.     

Initial glaucomatous optic disk and retinal nerve fiber layer abnormalities and their progression

We attempted to identify the initial glaucomatous changes of the optic disk and retinal nerve fiber layer and to analyze how these changes subsequently progressed. Of 61 eyes of 61 patients with ocular hypertension, 23 (38%) developed glaucoma during ten years of follow-up (range, five to 15 years). The initial sign of glaucomatous damage was diffuse enlargement of the optic disk cup in ten of 23 eyes or generalized thinning of the nerve fiber layer without localized changes in 12 of 23 eyes. We found localized optic disk damage in ten of 23 patients and localized retinal nerve fiber layer damage in 11 of 23 patients alone or in combination with diffuse damage. In 13 of 23 eyes, the cupping ended up in diffuse enlargement with even more profound thinning of the neural rim in the upper and lower temporal disk margins. There seems to be great variability in the appearance and progression of the initial glaucomatous optic disk and nerve fiber layer abnormalities in patients with increased intraocular pressure.     

海德堡视网膜断层扫描仪在开角型青光眼视盘检测中的意义

目的 探讨海德堡视网膜断层扫描仪(HRT)检测开角型青光眼视盘参数与视野损害的关系。评价HRT在早期诊断青光眼中的意义。方法 正常人26例(41只眼)，高眼压11例(16只眼)、原发性开角型青光眼28例(38只眼)。采用Humphrey全自动视野计、HRT分别进行视野、视盘形态检测。比较正常组、高眼压组、青光眼组HRT视盘检测参数．分析青光眼组视野检测的平均缺损(MD)与HRT视盘检测参数的关系。结果 正常组、高眼压组、青光眼组视杯面积、杯／盘面积比、盘沿面积、视杯形态测量指数、视网膜神经纤维层厚度差异有显著性。青光眼组的盘沿面积、杯／盘面积比、视杯形成测量指数、视网膜神经纤维层厚度与视野检测的平均缺损有显著相关。结论 HRT能够反映青光眼视盘改变，为临床早期诊断青光眼提供更多的信息。