Laser iridectomy in the management of chronic angle-closure glaucoma

Nineteen eyes of 16 patients (12 men and four women ranging in age from 41 to 75 years) underwent laser peripheral iridectomy for treatment of uncontrolled chronic angle-closure glaucoma (25 to 62 mm Hg). Five of eight eyes (62.5%) with glaucomatous cupping but full visual fields attained postiridectomy intraocular pressures of less than 22 mm Hg with medical therapy. Seven of nine eyes (77.7%) that had both glaucomatous optic disk damage and visual field loss before iridectomy had controlled intraocular pressures with medical therapy after iridectomy. Because laser iridectomy is safer than trabeculectomy, we recommend that it be the initial procedure in the treatment of chronic angle-closure glaucoma.     

Progressive Low-tension Glaucoma: Treatment to Stop Glaucomatous Cupping and Field Loss When These Progress Despite Normal Intraocular Pressure

Our thesis, inspired by the experience and teaching of Paul A. Chandler, is that after the optic discs have developed cupping and atrophy from elevated intraocular pressure they tend to become abnormally vulnerable and, in some cases, may continue to deteriorate even if the intraocular pressure is brought to the teens. At this stage they behave the same as in eyes with so-called low-tension glaucoma, which have developed progressive cupping and atrophy with pressures always in the teens. In either case, we find that the progression of cupping and field loss can be stopped by reducing the intraocular pressure to lower levels, preferably to 10 mm Hg or less. We have found that such low pressures are most reliably attained by surgery, using a special technique we call the shell tamponade filtration procedure, which involves the use of a glaucoma shell in conjunction with standard (full-thickness sclerostomy) filtration operations and certain specific operative and perioperative maneuvers. We present nine case reports illustrating our thesis. Glaucomatous cupping and loss of visual field were progressing relentlessly at normal pressures in each case. This progressive deterioration was shown to be arrested by reduction of the pressure to less than 12 mm Hg in 13 eyes.     

Optic disk and visual field correlations in primary open-angle and low-tension glaucoma

If the amount of visual field loss is less than expected from the amount of optic disk cupping in low-tension glaucoma compared with primary open-angle glaucoma, it might imply a difference between the two conditions in the type of optic nerve lesion produced. To test this hypothesis, three observers independently examined, in a masked fashion, optic disk stereoscopic photographs of 127 eyes with primary open-angle glaucoma and 71 eyes with low-tension glaucoma. For each stereoscopic photograph the observer predicted whether the visual field loss would be mild, moderate, or severe. The visual field were then classified, according to the number of sectors defective on the Goldmann perimeter chart, as having mild (1 to 15 sectors), moderate (16 to 30 sectors), or severe (more than 30 sectors) visual field loss. For no observer did the frequency of underpredictions or overpredictions in the two conditions differ significantly. The results of this study, thus, did not support the theory that the optic disk damage in primary open-angle glaucoma differs from that in low-tension glaucoma.     

Comparison of visual field defects in the low-tension glaucomas with those in the high-tension glaucomas

We compared the visual fields of 79 eyes (48 patients) with low-tension glaucoma (intraocular pressure less than 21 mm Hg) to the visual fields of 106 eyes (74 patients) with high-tension glaucoma (intraocular pressure greater than 30 mm Hg). Both groups had similar amounts of total field loss as determined by computerized threshold perimetry. Scotomas in the low-tension group had a steeper slope (P less than .001), were significantly closer to fixation (P less than .001), and had greater depth (P less than .001) than those in the high-tension group. These findings suggested that more than one causative factor is important in the production of optic nerve damage in glaucoma.     

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.     

Progressive optic nerve cupping and neural rim decrease in a patient with bilateral autosomal dominant optic nerve colobomas

PURPOSE: To document progressive optic nerve cupping and neural rim decrease in a patient with normal intraocular pressures and bilateral autosomal dominant optic nerve colobomas. METHODS: The ophthalmology records, stereoscopic fundus photographs, and visual fields of a 27-year-old woman with familial (autosomal dominant) optic nerve colobomas were reviewed. The appearance of the optic nerves was documented over a 13-year period (1985 to 1998). RESULTS: Despite repeatedly normal intraocular pressures, the patient showed progressive optic nerve cupping and neural rim decrease in both eyes. Visual field testing was available over a 5-year period (1993 to 1998) and was abnormal, but no progression was seen. CONCLUSIONS: This case of progressive cupping and neural rim decrease in a patient with autosomal dominant optic nerve coloboma in both eyes may provide insight into the optic nerve cupping associated with normal tension glaucoma. Careful follow-up of patients with optic disk colobomas or patients is indicated to detect possible optic nerve changes or field loss.     

Pattern-reversal electroretinograms from normotensive, hypertensive and glaucomatous eyes

Pattern-reversal electroretinograms (PERG) were recorded from 67 subjects, age 55-77 years, with normotensive (n = 19), hypertensive (n = 37) or glaucomatous (n = 11) eyes. The pathological intraocular pressure (IOP) ranged from 23 to 29 mm Hg in 21 eyes and from 30 to 43 mm Hg in 16 eyes. In 11 eyes (11 patients) manifest glaucoma was present (excavated optic disk, visual field defect). All examined subjects had normal visual acuity and clear optic media. The amplitude of the positive component of the PERG was measured. The mean PERG amplitude was 2.8 +/- 1.2 microV in the eyes with normal IOP (19 +/- 3 mm Hg), 2.2 +/- 1.0 microV in the eyes with moderately elevated IOP (26 +/- 2 mm Hg), 2.0 +/- 0.9 microV in the eyes with IOP above 30 mm Hg (33 +/- 4 mm Hg) and 1.1 +/- 0.6 microV in the glaucomatous eyes. Regression lines of PERG amplitudes versus age were calculated in all groups and showed a decrease in amplitude with increasing age. However, the correlation coefficients were not statistically significant. The decline with age was similar in all groups. The results indicate that the PERG amplitude is reduced in glaucomatous eyes and may be reduced also in ocular hypertension as well as with increasing age.     

Optic disk evaluation and utility of high-tech devices in the assessment of glaucoma.

BACKGROUND: Every clinician has at one time or another examined a patient who was misdiagnosed as having glaucoma or whose diagnosis of glaucoma was missed. Although glaucoma can exist with normal intraocular pressures, clinicians often rely on the presence of visual-field defects and the degree of optic disk cupping to direct care. However, assessment of cupping is but one small part of optic disk evaluation in glaucoma, and other features of the optic nerve head and retinal nerve fiber layer must be closely inspected to help diagnose borderline cases. In addition, glaucoma can exist without visual-field loss. High-tech devices offer an added dimension in the objective assessment of structure when subjective tests of function and/or ophthalmoscopic observations are equivocal. METHODS: This article details the various parameters of optic disk and retinal nerve fiber layer evaluation and their significance in the assessment of glaucoma. In addition, the role of four high-tech devices is evaluated for their utility in the assessment and progression of glaucomatous damage. CONCLUSIONS: When one attempts to classify a patient as having glaucoma, the degree of cupping and the presence or absence of visual field loss can be misleading. Prior to definitive diagnosis, a thorough evaluation of the optic disk and retinal nerve fiber layer, and appropriate use of high-tech devices, should help reduce the under-diagnosis and overdiagnosis of this disease.     

Optic disk size in chronic glaucoma: the Beijing eye study

PURPOSE: To evaluate whether eyes with chronic glaucoma have a larger or smaller optic disk than normal eyes. DESIGN: Population-based, cross-sectional cohort study. METHODS: The study included 4439 subjects out of 5324 subjects invited to participate with an age of 40+ years. Color optic disk photographs (45 degrees ) were morphometrically examined. RESULTS: After exclusion of aphakic eyes, pseudophakic eyes, and highly myopic eyes, data of 3989 subjects entered the statistical analysis. The mean optic disk area did not vary significantly (P > .05) between the nonglaucomatous group (2.61 +/- 0.50 mm(2)), eyes with glaucomatous appearance of the optic disk (2.69 +/- 0.63 mm(2)), eyes with glaucomatous optic disks and visual field defects (2.66 +/- 0.70 mm(2)), and eyes with elevated intraocular pressure (2.63 +/- 0.49 mm(2)). CONCLUSIONS: In adult Chinese, optic disk size may not markedly differ between normal eyes and eyes with chronic glaucoma.     

Combined use of frequency doubling perimetry and polarimetric measurements of retinal nerve fiber layer in glaucoma detection

PURPOSE: The aim of this study was to evaluate the diagnostic usefulness of the combined use of frequency-doubling technology (FDT) perimetry and polarimetry of the retinal nerve fiber layer. DESIGN: Cross-sectional study. METHODS: Seventy ocular hypertensive patients (normal optic disk and standard perimetry, elevated intraocular pressure [>21 mm Hg]), 59 patients with "preperimetric" open-angle glaucoma (glaucomatous optic disk atrophy, elevated intraocular pressure [>21 mm Hg], no visual field defect in standard perimetry), 105 patients with "perimetric" open-angle glaucoma (glaucomatous optic disk atrophy and clearly marked visual field defect), and 73 control subjects had FDT screening (protocol: C-20-5) and polarimetric measurements (GDx). Criteria for exclusion: optic disks larger than 4 mm(2), media opacities, patients younger than 33 years or older than 66 years. None of the subjects had earlier FDT perimetry. One eye of each patient and control subject entered the statistical evaluation. Database and statistical software were used for case-wise recalculation of all missed localized probability levels to create a FDT screening score. RESULTS: At a predefined specificity of 94.5% in control eyes, discrimination between "perimetric" glaucoma and normal subjects is superior using the FDT perimetry (sensitivity = 84.8%) in comparison to polarimetry (sensitivity = 63.8%), whereas sensitivity is similar with both methods in "preperimetric" patients (GDx, FDT: 25.4%). In several cases, patients classified as glaucomatous by the GDx are not the same patients as identified by the FDT perimetry. Therefore, a two-dimensional discrimination analysis can increase correct positive classification. Using a linear combination of the present FDT screening score and polarimetry ("the number"), 92.4% of "perimetric" glaucoma eyes and 44.1% of "preperimetric" glaucoma eyes have been classified as glaucomatous. CONCLUSION: Joint usage of polarimetry and FDT perimetry indicate that a combination of different techniques which can uncover different glaucoma properties, might be helpful in early glaucoma detection.     

Patterns of early visual field loss in open-angle glaucoma

We examined two groups of patients with primary open-angle glaucoma with distinctly different patterns of early visual field loss using two visual field indices: mean defect and loss variance. Patients were selected on the basis of visual field criteria only. Eight patients were selected for diffuse depression of the differential light sensitivity without localized scotomas (mean defect greater than 3.0 decibels, loss variance less than 10.0 decibels). Seven patients were selected for localized scotomas without diffuse depression of the differential light sensitivity (mean defect less than or equal to 3.0 decibels, loss variance greater than or equal to 20.0 decibels). Patients with diffuse depression manifested intraocular pressures that were higher (mean peak pressure +/- S.E.M., 27.6 +/- 1.2 mm Hg) than those with localized defects (22.4 +/- 1.4 mm Hg). The optic disk rim area of the localized loss group (mean +/- S.E.M., 1.02 +/- 0.15 mm2) was significantly smaller (P less than .05) than the disk rim area of the diffuse loss group (1.33 +/- 0.07 mm2). This difference was largely because of thinner temporal disk rims in the localized loss group. Different patterns of visual field loss may be caused by different mechanisms of glaucomatous optic nerve damage.     

Intraocular pressure response to topical dexamethasone as a predictor for the development of primary open-angle glaucoma

In a retrospective study we reviewed the records of 788 subjects who had been corticosteroid tested with 0.1% dexamethasone four times daily to one eye for six weeks. All subjects had normal kinetic visual fields and optic nerve heads in both eyes at the time of testing and were followed up for a minimum of five years. Some subjects had normal baseline intraocular pressures whereas others were considered to have ocular hypertension. Of 276 individuals who were high corticosteroid responders (intraocular pressure greater than 31 mm Hg during dexamethasone administration), 36 (13.0%) developed glaucomatous visual field loss during the follow-up period. Only nine of 261 individuals (3.4%) who were intermediate responders (intraocular pressure 20 to 31 mm Hg during dexamethasone administration) and none of 251 individuals who were low responders (intraocular pressure less than 20 mm Hg during dexamethasone administration) developed glaucomatous visual field loss. However, the ability of the intraocular pressure response to dexamethasone to predict the development of glaucomatous visual field loss was not as good as the predictive power of a multivariate model that included patient age, race, baseline intraocular pressure, baseline outflow facility, baseline cup/disk ratio, and systemic hypertension.     

正常眼压性青光眼诊断中存在的问题

患者具有典型的青光眼视盘损害、视野缺损、前房角开放、眼压正常，并排除眼部或全身性疾病引起的视神经病变，即可诊断为正常眼压性青光眼。准确的眼压测量、两次以上24小时眼压曲线描记以及对眼部和全身可能原发疾病的排除在诊断过程中至关重要。     

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.     

Diurnal fluctuation and concordance of intraocular pressure in glaucoma suspects and normal tension glaucoma patients

PURPOSE: The study objective was to determine the concordance of intraocular pressure (IOP) in glaucoma suspects (GS) and normal tension glaucoma (NTG) patients. METHODS: This was a retrospective review of diurnal curves of untreated GS and NTG patients. No subject had IOP greater than 21 mm Hg. We defined GS patients as having suspicious optic nerves with normal visual fields, and NTG patients as having glaucomatous optic nerves with associated visual field loss. Goldmann applanation tonometry was performed at 10:00, 13:00, 16:00, 19:00, 22:00, and 07:00. Linear association of OD and OS IOP was estimated using Pearson correlation coefficient (r). The diurnal period was divided into 7 time intervals of 3, 6, 9, 12, 15, 18, and 21 hours, and the absolute difference in change in IOP between fellow eyes and probability that it was within 3 mm Hg were calculated. RESULTS: The study included 68 GS and 95 NTG subjects. The diurnal curves of the OD and OS showed a parallel course in both groups. The average correlations (r) of OD and OS IOP over the 6 time points were 0.78 and 0.81 for GS and NTG, respectively. The mean absolute difference in IOP change between OD and OS over the 6 time intervals ranged between 1.4 and 1.9 mm Hg for GS, and 1.3 and 1.5 mm Hg for NTG subjects. The probability that this difference was within 3 mm Hg ranged between 87% and 94% for GS, and 86% and 93% for NTG subjects. CONCLUSIONS: The diurnal variation in IOP between the 2 eyes in GS and NTG is largely concordant in approximately 90% of the time.     

Bilateral visual field defects with optic disc drusen and secondary open angle glaucoma with PEX--clinical correlation with the HRA

BACKGROUND: Arcuate visual field defects are a typical sign of glaucomatous damage. Elevated intraocular pressure in combination with pseudoexfoliation syndrome (PSX) manifests the diagnosis glaucoma. Beyond this state, in microdiscs with optic disc drusen, the exact classification of the visual field defects is crucial. CASE REPORT: A 57-year-old male with pseudoexfoliation glaucoma was referred because of progressive glaucomatous visual field defects. The visual acuity was right 20/40 and left 20/25. Maximum intraocular pressure was 36 mm Hg. A simple optic nerve atrophy was diagnosed superonasally. The optic disc size was OD 2.24 mm(2) and OS 1.89 mm(2) (HRT I). An Ultrasound B-mode scan demonstrated the diagnosis of optic disc drusen. Over a follow-up of 1 year, a growth tendency was observed, especially in the superonasal quadrant. The mulberry-shaped surface of the drusen was visualized with infrared reflection images (HRA II, 830 nm). Confocal scanning laser ophthalmoscopy (HRA II, excitation 488 nm, 500 nm notch filter) showed an increased intrapapapillary autofluorescence (> 50 % papillary area: OD 1.67 mm(2), OS 1.26 mm(2)). This technique could detect drusen in areas that looked normal in classical retinoscopy. CONCLUSION: The differential diagnosis of arcuate scotomas includes simple optic nerve atrophy and glaucomatous optic nerve atrophy. Optic disc drusen in glaucoma eyes can obscure the main cause of progressive visual field loss. Superficial optic disc drusen can be measured planimetrically over the years. An adequate reduction of intraocular pressure should be realized in these eyes.     

Can frequency-doubling technology and short-wavelength automated perimetries detect visual field defects before standard automated perimetry in patients with preperimetric glaucoma?

PURPOSE: To assess the ability of frequency-doubling technology (FDT) perimetry and short-wavelength automated perimetry (SWAP) to detect glaucomatous damage in preperimetric glaucoma subjects. PARTICIPANTS: Two hundred seventy-eight eyes of 278 subjects categorized as normal eyes [n=98; intraocular pressure <20 mm Hg, normal optic disc appearance, and standard automated perimetry (SAP)]; preperimetric glaucoma eyes (n=109; normal SAP and retinal nerve fiber layer defects or localized optic disc notching and thinning); and glaucoma patients (n=71; intraocular pressure >21 mm Hg, optic disc compatible with glaucoma, and abnormal SAP). METHODS: The preperimetric glaucoma group underwent at least 2 reliable full-threshold 24-2 Humphrey SAPs, full-threshold C-20 FDT, full-threshold 24-2 SWAP, optic disc topography using the Heidelberg Retina Tomograph II, laser polarimetry using the GDx VCC, and Optical Coherence Tomography (Zeiss Stratus OCT 3000). Receiver operating characteristic curves were plotted for the main Heidelberg Retina Tomograph, Optical Coherence Tomography, and GDx VCC parameters for the normal and glaucoma patients. The area under the receiver operating characteristic curve was used to determine the parameters indicating glaucomatous damage in the optic disc or retinal nerve fiber layer, which were used to establish additional subgroups of patients with preperimetric glaucoma. FDT and SWAP sensitivities were calculated for the patient subsets with structural damage and normal SAP. RESULTS: At least 20% of the patients with preperimetric glaucoma demonstrated functional losses in FDT and SWAP. The more severe the structural damage, the greater the sensitivity for detecting glaucomatous visual field losses. CONCLUSIONS: FDT and SWAP detect functional losses in cases of suspected glaucoma before glaucomatous losses detected by SAP.     

Primary open angle glaucoma in cornea plana masked by false normal applanation tonometry (Goldman) - a case report

BACKGROUND: Cornea plana is a rare syndrome, which leads to a flat corneal curvature due to a reduced sclero-corneal angle. Depending on the regularity of the corneal astigmatism the frequently resulting hyperopia may be difficult to compensate for. Because of the flatness of the cornea the anterior chamber is also flat, the anterior chamber angle can be restricted, and the applanatory intraocular pressures (IOPs) are measured too low. A primary open angle glaucoma is therefore not diagnosed for a long time, until changes of the optic nerve head occur.Patient and methods We report on a 66-year-old male with cornea plana. Although his intraocular pressure (IOP), measured with an applanation tonometer (Goldmann), had always been normal (< 21 mm Hg), he suffered from an increasing glaucomatous atrophy of the optic disc. We carried out a complete ophthalmological investigation, including keratometry and corneal topography analysis (TMS-1, Tomey). Furthermore, visual field was determined (G1, Octopus) and the optic nerve heads were documented and analysed by papillometry. A 48-hour tension profile was worked out for both eyes including applanation and Schi?tz tonometry.Results The central refractive power of the cornea was 31 diopters and the cornea seemed to be flattened on slit lamp evaluation. The glaucomatous atrophy of the optic disc was more pronounced in the OD than in the OS (OD=neuroretinal rim loss in the upper part, at the bottom and in the lateral part of the optic disc, OS=laterally distinct neuroretinal rim loss). While the anterior parts of the eye were shortened (depth of the anterior chamber was OD/OS=1.9 mm), a macrophthalmus posterior was stated (axial length OD=25.78 mm, OS=25.72 mm). However, the IOPs were measured below 21 mm Hg by applanation during the entire tension analysis, comparable values measured with the Schi?tz tonometer showed values above 21 mm Hg. We converted the applanatory IOP values according to the flat corneal power, as described in literature (addition of 1 mm Hg to the applanatory values per 3 diopters decreased corneal power). The tension analysis now showed increased values, as expected after observation of the glaucomatous excavated optic nerve head.Conclusion In patients with cornea plana applanatory IOPs are measured too low. Therefore in case of very flat corneas a mathematical correction of the applanatory IOP should be carried out, in order to diagnose a primary open angle glaucoma early enough.     

Visual field change in low-tension glaucoma over a five-year follow-up

There is some evidence that the nature and progression of disease in low-tension glaucoma may be distinct from other open-angle glaucomas. The authors assessed visual field change by retrospective case review of all patients treated for low-tension glaucoma by the Glaucoma Service, Wills Eye Hospital, for at least 5 years. Sixty-two glaucomatous eyes of 36 patients were identified. All eyes were treated medically and 40 (65%) underwent at least one surgical procedure. Twenty-eight eyes (47%) had initial field loss confined to a single hemi-field and in the remainder both hemi-fields were involved. Thirty of 57 eyes (53%) showed progression at 3 years and 38 (62%) of 57 had progressed by 5 years. A dense scotoma extending from the nasal periphery toward fixation was the most common visual field defect. The rate of field change in this population is significantly greater than in a cohort of primary open-angle glaucoma patients also seen at Wills Eye Hospital, but who had elevated intraocular pressures. Patterns of field loss and rate of progression in this low-tension glaucoma population suggest that the natural history of low-tension glaucoma differs from high-tension open-angle glaucoma.     

Optic Disc Cupping in Arteritic Anterior Ischemic Optic Neuropathy Resembles Glaucomatous Cupping

Five cases of anterior ischemic optic neuropathy secondary to biopsy-proven giant cell arteritis are presented. In each case, cupping of the optic disc, which closely resembled glaucomatous cupping, was observed in the affected eye. The presence of glaucoma was ruled out on the basis of normal intraocular pressures and normal tonographic measurements of facility of outflow. These cases indicate that arteritic ischemic optic neuropathy can result in optic disc cupping, which closely resembles glaucomatous cupping. The similarities in the appearance of cupping of these discs with that seen in eyes with glaucoma suggest that the pathogenesis of cupping in glaucoma and in arteritic ischemic optic neuropathy may share some common mechanisms.