Glaucoma in a rural population of southern India: the Aravind comprehensive eye survey

PURPOSE: To determine the prevalence of glaucoma and risk factors for primary open-angle glaucoma in a rural population of southern India. DESIGN: A population-based cross-sectional study. PARTICIPANTS: A total of 5150 subjects aged 40 years and older from 50 clusters representative of three southern districts of Tamil Nadu in southern India. METHODS: All participants had a comprehensive eye examination at the base hospital, including visual acuity using logarithm of the minimum angle of resolution illiterate E charts and refraction, slit-lamp biomicroscopy, gonioscopy, applanation tonometry, dilated fundus examinations, and automated central 24-2 full-threshold perimetry. MAIN OUTCOME MEASURES: Definite primary open-angle glaucoma (POAG) was defined as angles open on gonioscopy and glaucomatous optic disc changes with matching visual field defects, whereas ocular hypertension was defined as intraocular pressure (IOP) greater than 21 mmHg without glaucomatous optic disc damage and visual field defects in the presence of an open angle. Manifest primary angle-closure glaucoma (PACG) was defined as glaucomatous optic disc damage or glaucomatous visual field defects with the anterior chamber angle partly or totally closed, appositional angle closure or synechiae in the angle, and absence of signs of secondary angle closure. Secondary glaucoma was defined as glaucomatous optic nerve damage and/or visual field abnormalities suggestive of glaucoma with ocular disorders that contribute to a secondary elevation in IOP. RESULTS: The prevalence (95% confidence interval) of any glaucoma was 2.6% (2.2, 3.0), of POAG it was 1.7% (1.3, 2.1), and if PACG it was 0.5% (0.3, 0.7), and secondary glaucoma excluding pseudoexfoliation was 0.3% (0.2,0.5). On multivariate analysis, increasing age, male gender, myopia greater than 1 diopter, and pseudoexfoliation were significantly associated with POAG. After best correction, 18 persons (20.9%) with POAG were blind in either eye because of glaucoma, including 6 who were bilaterally blind and an additional 12 persons with unilateral blindness because of glaucomatous optic neuropathy in that eye. Of those identified with POAG, 93.0% had not been previously diagnosed with POAG. CONCLUSIONS: The prevalence of glaucoma in this population is not lower than that reported for white populations elsewhere. A large proportion of those with POAG had not been previously diagnosed. One fifth of those with POAG had blindness in one or both eyes from glaucoma. Early detection of glaucoma in this population will reduce the burden of blindness in India.     

Prevalence of open-angle glaucoma and ocular hypertension in Latinos: the Los Angeles Latino Eye Study

OBJECTIVE: To estimate age- and gender-specific prevalences of ocular hypertension and open-angle glaucoma (OAG) in adult Latinos. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in Los Angeles, California. METHODS: The study cohort consisted of all self-identified Latinos of primarily Mexican ancestry 40 years and older residing in 6 census tracts in La Puente, California. All participants underwent a complete ophthalmologic examination, including measurement of intraocular pressure (IOP), visual field (VF) testing using an automated field analyzer, and simultaneous stereoscopic fundus photography of the optic disc. Ocular hypertension was defined as IOP of >21 mmHg and the absence of optic disc damage or abnormal VF test results. Open-angle glaucoma was defined as the presence of an open angle and various criteria that included a glaucomatous VF abnormality and/or evidence of glaucomatous optic disc damage in at least one eye. MAIN OUTCOME MEASURES: Prevalence of open-angle glaucoma and ocular hypertension. RESULTS: For the 6142 participants who underwent a complete ophthalmologic examination at the clinical center, the prevalence of OAG was 4.74% (95% confidence interval [CI], 4.22%-5.30%). The prevalence of ocular hypertension was 3.56% (95% CI, 3.12%-4.06%). The prevalences of OAG and ocular hypertension were higher in older Latinos than in younger Latinos (P<0.0001). No gender-related differences in prevalences of OAG and ocular hypertension were present. The mean IOP, mean deviation, and mean vertical cup-disc ratio in persons with OAG were 17 mmHg, -9.6 decibels, and 0.6, respectively. Seventy-five percent of Latinos with OAG and 75% of Latinos with ocular hypertension were previously undiagnosed. Further, 17% of Latinos with OAG and 23% of Latinos with ocular hypertension had received treatment for "glaucoma." CONCLUSION: Our data suggest that the prevalence of OAG is high among Latinos of Mexican ancestry. The higher prevalence of OAG in older Latinos emphasizes the public health importance of providing eye care services for the early diagnosis and management of this condition in Latinos.     

Intraocular pressure and prevalence of glaucoma in elderly people in Finland: a population-based study

The distribution of intraocular pressure (IOP) and the prevalence of glaucoma and their correlates were studied in a population-based study of inhabitants aged 70 years or older of three communities in the county of Oulu, Finland. 500 of the 560 eligible subjects (89%) were examined. IOP was measured using applanation tonometry. The diagnosis of glaucoma (or suspected glaucoma) was based on previous history and/or characteristic optic disc changes assessed first by ophthalmoscopy and later by photographic evaluation.No correlation existed between IOP level and age, but IOP was higher in women than in men. Glaucoma occurred in 12% of the participants (60 of 500 persons). In 42 of the 60 persons (8% of the participants) glaucoma had been diagnosed before this survey: non-exfoliative open-angle glaucoma in 15 persons (3.0%), bilateral or unilateral exfoliative open-angle glaucoma in 19 persons (3.8%), and congestive glaucoma in 8 persons (1.6%). In another 18 persons (4% of the participants) new open-angle glaucoma was detected, one third of these were exfoliative. In addition, 6% of the study population had suspected glaucomatous disc changes. In all new glaucoma cases and in all suspected cases the IOP was lower than 25 mmHg. Ocular hypertension (>25 mmHg) without disc changes was found in 2%.     

The amount of intraocular pressure rise during pharmacological pupillary dilatation is an indicator of the likelihood of future progression of glaucoma

AIM: To determine if there is a relationship between the amount of increase in IOP following dilatation with a cycloplegic agent and the future course of glaucoma. METHOD: A retrospective chart review of 100 eyes from 55 subjects with open-angle glaucoma who had had IOP measured before and after pharmacological pupillary dilatation was performed to establish the rate of progression of glaucoma, based on serial evaluation of the visual fields using the glaucoma staging system 2 (GSS 2), and optic discs using the disc damage likelihood scale (DDLS). Progressive visual field loss was defined as an increase of two or more stages with the GSS 2 and progressive deterioration of the disc was defined as an increase of two or more stages with the DDLS. Mean follow-up time was 7.2 years. RESULTS: A total of 26 eyes showed glaucomatous progression. The likelihood of progression of glaucoma was related to the amount of IOP increase after pharmacological pupillary dilatation. For every 1 mmHg increase in IOP, the odds of progression increased 24% (p = 0.008). The likelihood of progression of glaucoma, however, was not related to the baseline IOP, which was 20.63 mmHg (SD = 4.59 mmHg) in those showing deterioration of disc or field and 19.72 mmHg (SD = 5.32 mmHg) in those not worsening according to our definition. CONCLUSION: In patients with open-angle glaucoma, the amount of increase in IOP caused by pharmacological pupillary dilatation is related to the likelihood of future progression of glaucoma.     

Which patients are treated for glaucoma? An observational analysis

PURPOSE: More than one million patients in the United States are treated for glaucoma, although little is known about the typical clinical characteristics of this group of patients and the type of therapy they receive. This study was conducted to describe the demographic and diagnostic characteristics of patients beginning long-term drug therapy for glaucoma. METHODS: This cross-sectional study included 544 patients beginning topical glaucoma medication regimens who received care at a group model health-maintenance organization (HMO) located in central Massachusetts. The primary medical records of 544 patients beginning topical glaucoma medication between 1987 and 1990 were reviewed to ascertain the presence of three clinical findings: intraocular pressure (IOP) > or = 22 mmHg; optic disc changes including cup-to-disc ratio > or = 0.8, cup-to-disc asymmetry > or = 0.2, or morphologic disc changes consistent with glaucomatous optic neuropathy; and visual field defect consistent with glaucoma. RESULTS: A majority of the 544 patients (86%) were diagnosed as having primary open-angle glaucoma (POAG) by their physicians. Almost half (44.7%) of these patients had only an elevation in IOP without other clinical findings, and 9% met none of the above criteria for glaucoma according to information in the medical record. CONCLUSION: In this setting, most patients who were prescribed drug therapy for POAG were treated for an elevation in IOP alone in the absence of other ophthalmologic characteristics of glaucoma.     

Crete, Greece glaucoma study

PURPOSE: To investigate the prevalence of primary open-angle glaucoma (POAG) in a randomized sample of the inhabitants of the island of Crete. PATIENTS AND METHODS: In 18 different villages in all four prefectures of the island of Crete, patients were randomly selected from 1993 through 1998, and an in situ study was accomplished. The sampling fraction (covered by the 1991 census) in each village was approximately 5%. Patients were considered to have POAG when the morphologic aspect of a glaucomatous optic disc was present, and/or a nerve fiber layer defect and a visual field defect was present. The presence of Pseudoexfoliation syndrome (PEX) and pseudoexfoliative glaucoma (PEXG) was also investigated. RESULTS: The prevalence of glaucoma in Crete was 2.80%. Of those diagnosed with POAG, 9.67% had an intraocular pressure (IOP) under 21 mm Hg, and 25.80% had PEX. The prevalence of simple ocular hypertension without glaucoma was found in 6.58% of the patients. The ratio of subjects with hypertensive glaucoma to those with simple ocular hypertension was 1:2.6. CONCLUSION: The prevalence of POAG and exfoliation glaucoma appears to be quite high in Crete. Further research will be needed to set more accurate criteria for earlier diagnosis and to enable more efficient organization of the health care system.     

Exfoliation syndrome and exfoliation glaucoma

Exfoliation syndrome abnormal deposition in the anterior segment of the eye of an unknown substance thought to be related to elastic fibres and basement membrane components is associated with accelerated cataract progression. increased frequency of intraoperative and postoperative complications and increased risk for glaucoma and. therefore, is a clinically important finding. A clear association has been shown with age. The syndrome occurs worldwide but its prevalence seems to vary from country to country. The best-known sign of exfoliation syndrome is deposits of greyish-white material on the anterior lens surface. Sometimes exfoliation material can also be seen at the pupillary border, on the anterior iris surface, corneal endothelium, and on the anterior vitreous face. When clinically detected, exfoliation syndrome is somewhat more often unilateral than bilateral. According to recent investigations clinically unilateral exfoliation syndrome is probably never truly unilateral but rather asymmetric, because exfoliation material has been detected ultrastructurally and immunohistochemically around iris blood vessels of the nonexfoliative fellow eyes. Indeed, electron microscopy identifies in various organs of patients with exfoliation syndrome fibrils similar to those seen in intraocular exfoliation deposits. Other clinical signs associated with exfoliation syndrome are pigment dispersion, transillumination defects of the iris and reduced response to mydriatics. In unilateral exfoliation syndrome, intraocular pressure (IOP) of the exfoliative eye is approximately 2 mmHg higher than IOP of the nonexfoliative fellow eye. Whether elevated IOP, vascular changes or exfoliation syndrome itself is the main factor causing optic nerve head damage and conversion of an exfoliative eye to glaucomatous, is not known. Glaucoma in the exfoliation syndrome has been shown to have a more serious clinical course than in primary open-angle glaucoma (POAG). At the time of diagnosis, IOP and its diurnal variation are generally higher and visual field defects tend to be greater in exfoliation glaucoma than in POAG. Because the decrease in lOP variation and lowering of the mean IOP level has been shown to improve visual field prognosis more in exfoliation glaucoma than in POAG, the glaucomatous process is considered to be more pressure-related in exfoliation glaucoma. Furthermore, progression of optic disc damage has been shown to be similar in exfoliation glaucoma and POAG when lOPs are lowered to a comparable level by the treatment. However, vascular disturbances in the posterior segment of the eye might after all be of equal importance in these two types of glaucoma; optic disc haemorrhages and venous occlusions have been reported to be as frequent in exfoliation glaucoma as in POAG. Perhaps in exfoliation glaucoma circullatory disturbances combined with high IOP lead to a particularly relentlessly progressing form of the disease.     

High prevalence of glaucoma in patients with sleep apnea syndrome.

OBJECTIVE: To determine the prevalence of glaucoma in sleep apnea syndrome (SAS), an entity characterized by repetitive upper airway obstructions during sleep, inducing hypoxia and sleep disruption with the risk of cardiovascular and neurologic sequelae. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 114 white patients consecutively referred for polysomnographic evaluation of suspected SAS. INTERVENTION: Complete ophthalmologic examination, including computerized perimetry and simultaneous stereoscopic optic disc photographs. MAIN OUTCOME MEASURES: Spearman rank correlations between the respiratory disturbance index during night sleep (RDI), a value used to diagnose and grade SAS, and visual acuity, intraocular pressure (IOP), visual field indices, presence or absence of glaucomatous optic disc changes, and diagnosis of glaucoma. Each correlation was controlled for age and body mass index. To compare proportions of patients harboring glaucoma, the binomial test was used. RESULTS: Sixty-nine (60.5%) of the 114 patients had an RDI > or =10, which indicates SAS. Three patients had primary open-angle glaucoma, and two had normal-tension glaucoma. All patients with glaucoma had SAS. The observed prevalence of glaucoma in patients with SAS (5 of 69, 7.2%) was significantly higher than expected in a white population (2%) (P = 0.01). The RDI correlated positively with IOP (P = 0.025), visual field loss variance (P = 0.03), glaucomatous optic disc changes (P = 0.001), and diagnosis of glaucoma (P = 0.01). CONCLUSIONS: Patients with SAS constitute a high-risk population for glaucoma and should therefore be screened for glaucoma.     

Angle-closure glaucoma in an urban population in southern India. The Andhra Pradesh eye disease study

OBJECTIVE: To assess the prevalence and features of angle-closure glaucoma (ACG) in an urban population in southern India. DESIGN: A population-based, cross-sectional study. PARTICIPANTS: A total of 2522 (85.4% of those eligible) persons of all ages, including 1399 persons 30 years of age or older, from 24 clusters representative of the population of Hyderabad city. TESTING: The participants underwent an interview and detailed eye examination that included logarithm of minimum angle of resolution visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, and gonioscopy; pupil dilatation and stereoscopic fundus evaluation was performed if the risk of angle-closure as a result of dilatation was not believed to be imminent. Humphrey threshold 24-2 visual fields (Humphrey Instruments Inc., San Leandro, CA) were performed when indicated by standardized criteria for disc damage or if intraocular pressure (IOP) was 22 mmHg or more. MAIN OUTCOME MEASURES: An occludable angle was defined as pigmented posterior trabecular meshwork not visible by gonioscopy in three quarters or more of the angle circumference. Manifest primary angle-closure glaucoma (PACG) was defined as IOP of 22 mmHg or more or glaucomatous optic disc damage with visual field loss in the presence of an occludable angle. An IOP of 22 mmHg or more or glaucomatous optic disc damage in the presence of an occludable angle secondary to an obvious cause was defined as secondary ACG. RESULTS: Manifest PACG and occludable angles without ACG were present in 12 and 24 participants, respectively, with age- and gender-adjusted prevalence (95% confidence interval [CI]) of 0.71% (0.34%-1.31%) and 1.41% (0.73%-2.09%) in participants 30 years of age or older, and 1.08% (0.36%-1.80%) and 2.21% (1.15%-3.27%) in participants 40 years of age or older, respectively. With multivariate analysis, the prevalence of these two conditions considered together increased significantly with age (P < 0.001); although not statistically significant, these were more common in females (odds ratio 1.70; 95% CI, 0.82-3.54) and in those belonging to lower socioeconomic strata as compared with middle and upper strata (odds ratio, 1.82; 95% CI, 0.88-3.74). The odds of manifest PACG were higher in the presence of hyperopia of more than 2 diopters ([D]; odds ratio, 3.69; 95% CI, 0.89-15.2). Only four of 12 participants (33.3%) with manifest PACG had been previously diagnosed, and one of 12 (8.3%) had peripheral iridotomy performed previously. Manifest PACG had caused blindness in one or both eyes in five of these 12 participants (41.7%); best-corrected distance visual acuity less than 20/400 in one or both eyes in four patients, and acuity less than 20/200 in one eye in another patient. Most (83.3%) of those with manifest PACG could be classified as having chronic form of the disease. We may have underestimated manifest PACG because visual fields were per- formed only on those with clinical suspicion of optic disc damage. Secondary ACG was present in two participants. CONCLUSIONS: The prevalence of PACG in this urban population in southern India is close to that reported recently in a Mongolian population. A large proportion of the PACG in this population was undiagnosed and untreated. Because visual loss resulting from PACG is potentially preventable if peripheral iridotomy or iridectomy is performed in the early stage, strategies for early detection of PACG could reduce the high risk of blindness resulting from PACG seen in this urban population in India.     

原发性开角型青光眼HRT视盘结构参数与视野缺损相关性研究

目的探讨出现视野缺损与未出现视野缺损的原发性开角型青光眼视盘结构参数的异同及视盘参数与视野平均缺损（MD）的相关性。方法应用海德堡视网膜断层扫描仪（HRT-Ⅱ）和Octopus101视野G2程序对29例（50只眼）原发性开角型青光眼患者进行检查，对出现视野缺损与未出现视野缺损的原发性开角型青光眼视盘结构参数进行比较，检测结果进行t检验；对出现视野缺损的原发性开角型青光眼组的视盘各参数与视野平均缺损进行简单相关分析。结果视野出现缺损组与未出现缺损组的原发性开角型青光眼患者的视盘参数除视盘面积和轮廓线高度变化值外，其余各视盘参数间差异均有显著性（P〈0．01）；对出现视野缺损的原发性开角型青光眼患者HRT视盘各参数与MD进行相关分析显示，盘沿面积与MD间相关性最强（r=0．65，P=0．001）。结论HRT视盘参数能够较准确反映与视野损害相一致的青光眼性视盘改变，盘沿面积在HRT众多参数中最能反映青光眼的视野平均缺损程度。     

Prevalence of glaucoma. The Beaver Dam Eye Study.

PURPOSE: The purpose of this study is to determine the prevalence of glaucoma in the population participating in the Beaver Dam Eye Study (n = 4926). METHODS: All subjects were examined according to standard protocols, which included applanation tonometry, examination of the anterior chamber, perimetry, grading of fundus photographs of the optic disc, and a medical history interview. Visual field, cup-to-disc ratio, and intraocular pressure (IOP) criteria were used to define the presence of open-angle glaucoma. Definite open-angle glaucoma was defined by the presence of any two or all three of the following: abnormal visual field, large or asymmetric cup-to-disc ratio, high IOP. RESULTS: The overall prevalence of definite open-angle glaucoma was 2.1%. The prevalence increased with age from 0.9% in people 43 to 54 years of age to 4.7% in people 75 years of age or older. There was no significant effect of sex after adjusting for age. Of the 104 cases of definite open-angle glaucoma, 33 had IOPs less than 22 mmHg in the involved eye. Hemorrhage on the optic disc was found in 46 people; 2 of these had glaucoma. Narrow-angle glaucoma was rare, with two definite cases in the population. CONCLUSION: The prevalence of open-angle glaucoma in Beaver Dam is similar to that in other white populations. Findings from this study re-emphasize the notion that estimates of glaucoma prevalence should be based on assessing multiple risk indicators.     

Screening for glaucoma in a general population with the non-mydriatic fundus camera and the frequency doubling perimeter

PURPOSE: To evaluate the usefulness of non-mydriatic fundus camera (NMFu-camera) and frequency doubling perimeter (FDP) for detecting glaucoma in a general population. METHODS: This prospective observational multicenter study consisted in screening for glaucoma in the populations of three Belgian cities. Intraocular pressure (IOP) was measured with non-contact pneumo-tonometer (NCT) and applanation tonometry (AT) if NCT IOP was > or = 17 mmHg. Visual field was screened with FDP (C-20-5) and digitized optic disc photographs (ODPs) were taken with NMFu-camera. FDP was considered abnormal if at least one defective point was found. ODPs were graded as normal or glaucomatous by consensus of three glaucoma specialists. Optic disc and visual field results were matched per eye. Subjects with known ocular hypertension and/or treated primary open angle glaucoma were excluded from the analysis. RESULTS: A total of 1620 subjects were included in the study. Their mean age was 63.2 years. AT IOP was > 21 mmHg in 8.2%. A total of 98.1% of ODPs could be interpreted. Glaucomatous optic discs were detected in 3.5% of the subjects. In this group only 24% had an AT IOP > or = 22 mmHg. FDP was abnormal in 44.5%. The sensitivity and specificity of FDP to identify patients with an optic disc graded as glaucomatous were 58.6% and 64.3% respectively. CONCLUSIONS: The combined use of the NMFu-camera and the FDP is a feasible method for an initial glaucoma mass screening. NMFu-camera may be a useful and quick method to screen for glaucomatous damage in a community. FDP in screening strategy was revealed to be not sensitive enough when setting the cut-off value at one defective test location. IOP measurements were confirmed to be a poor tool to detect glaucomatous damage.     

Screening performance of functional and structural measurements of neural damage in open-angle glaucoma: a case-control study from the Baltimore Eye Survey

PURPOSE: To compare the sensitivity and specificity of four approaches to glaucoma screening. METHODS: Case patients were persons with possible, probable, or definite glaucomatous optic nerve damage, as judged by a glaucoma specialist using Humphrey 24-2 threshold findings and clinical assessment of disc and nerve fiber layer, identified in the population-based Baltimore Eye Survey Follow-up Study. Control patients were participants in the same study, frequency-matched for age, without evidence of glaucomatous optic nerve damage. Participants underwent optic disc photography (Topcon ImageNet), disc imaging (GlaucomaScope), scanning laser polarimetry (Nerve Fiber Analyzer), and suprathreshold field testing (Dicon). RESULTS: A total of 100 case patients with open-angle glaucoma and 149 control patients were included. Objective imaging had the best screening performance. For the GlaucomaScope, a criterion of cup-to-disc ratio of -0.68 had a sensitivity of 72% and specificity of 82% for detecting eyes with definite or probable glaucomatous optic nerve damage. For the nerve fiber layer, a criterion of The Number as > or = 20 had a sensitivity of 69% and specificity of 77% for detecting eyes with definite or probable glaucomatous optic nerve damage. Usable data could be obtained in 93% of participants with the Dicon and the Nerve Fiber Analyzer and in 82% and 87% of participants with the GlaucomaScope and Topcon instruments, respectively. CONCLUSIONS: Vertical cup-to-disc ratio, as measured by the GlaucomaScope or Topcon instruments, and the Nerve Fiber Layer neural network Number had the best combination of sensitivity and specificity among the instruments tested. The Nerve Fiber Analyzer had the highest percentage of participants with usable data.     

Prevalence of primary open-angle glaucoma in a Spanish population: the Segovia study

PURPOSE: To determine the prevalence of primary open-angle glaucoma (POAG) in Segovia, Spain. METHODS: We conducted a cross-sectional, population-based epidemiologic study, the target population of which was residents of Segovia, Spain, aged 40 to 79 years. A sample of 569 subjects was randomly selected in a stratified manner according to gender and age groups. All participants underwent a complete ophthalmic examination that included measurement of visual acuity and refraction, tonometry, anterior segment biomicroscopy, funduscopy, stereoscopic photographs of the optic nerve head, and automated white-on-white visual field testing. Two independent observers evaluated the optic nerve photographs and visual fields. The diagnosis of POAG was established when any eye had an open angle and a glaucomatous optic nerve and glaucomatous visual field. The prevalence of POAG in the population was estimated from the prevalence in the complete sample and the patients already diagnosed at the only glaucoma service in the city. RESULTS: The estimated prevalences (99% confidence interval) in the population were, respectively, 2.1% (1.9-2.3%), and 1.7% (1.6-1.8%) for POAG and ocular hypertension. The prevalence of POAG increased with age (P < 0.005) and tended to be greater (P = 0.054) in men (2.4%) than women (1.7%). CONCLUSION: The prevalence of POAG in this Segovia population is 2.1%, similar to that estimated in previous studies performed in predominantly Caucasian populations.     

Failure of medical therapy despite normal intraocular pressure

The disease glaucoma is now defined by characteristic optic disc and visual field change, without specific reference to the intraocular pressure (IOP). Success of treatment is no longer judged by the mere attainment of IOP less than 21 mmHg. Controversy remains, however, in deciding appropriate management where optic disc and/or visual field damage continues to progress despite a 'normal' IOP having been achieved with medical treatment. A panel of international glaucoma experts has provided management recommendations in four clinical scenarios--open-angle glaucoma, open-angle glaucoma in a myopic contact lens wearer, uveitic glaucoma and open-angle glaucoma in combination with visually significant cataract--where optic nerve and visual field progression has continued despite an IOP less than 21 mmHg on full medical treatment. Surgical intervention with mitomycin trabeculectomy is the most favoured further therapy.     

Absolute filling defects of the optic disc in fluorescein angiograms in glaucoma--a retrospective clinical study

BACKGROUND: Analysis of clinical importance of the size of filling defects in fluorescein angiograms in primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), ocular hypertension and subjects with physiological excavations in comparison to visual field loss, optic nerve head morphology and hemodynamics. PATIENTS AND METHODS: 75 patients (POAG, NTG, ocular hypertension) and 10 healthy subjects with physiological excavations were included in this study. In digitized video fluorescein angiograms (Scanning Laser Ophthalmoscope) the size of absolute filling defects of the optic disc was quantified in the early venous phase and expressed by percentage of the optic disc. Visual fields were obtained by conventional static perimetry (Humphrey 24-2) and graded in stages of glaucoma visual field defects (Aulhorn I-V). Optic disc excavations were evaluated as cup-to-disc-area-ratios. RESULTS: The filling defects correlated with the visual-field loss stages of Aulhorn and the visual field indices MD (mean deviation), PSD (pattern standard deviation) and CPSD (corrected pattern standard deviation). There was no correlation with the index SF (short-term fluctuation) and with systemic hemodynamics (blood pressure, perfusion pressure) or the IOP. Absolute filling defects correlated with the cup-to-disc-area-ratio in NTG. The absolute filling defects were larger in patients with glaucoma (POAG, NTG) in comparison to patients without glaucomatous visual field loss (ocular hypertension, glaucoma-like discs). No difference of filling defects was found in the glaucoma group (POAG, NTG). Patients with NTG had larger excavations and lower systolic blood pressures than patients with POAG. CONCLUSION: The size of fluorescein filling defects may be useful as a parameter for the evaluation of an ischemic lesion of the optic nerve head. Absolute filling defects may differentiate POAG from ocular hypertension and NTG from glaucoma-like discs without field defects. The results support the hypothesis that in POAG and NTG disturbances of the circulation result in similar filling defects of the optic disc and visual field loss.     

Morphology of the optic papilla in glaucoma. II. Secondary chronic open angle glaucoma

Previous studies have shown that the chronic open-angle glaucomas form a heterogeneous spectrum of diseases which have in common an open anterior chamber angle and glaucomatous optic nerve damage. Purpose of this study was to evaluate whether the appearance of the optic disc shows specific features among various types of secondary chronic open-angle glaucoma. METHODS: Clinical data and color-stereo optic disc photographs of 126 patients with pseudoexfoliative glaucoma and 47 patients with pigmentary glaucoma were compared with those of 501 patients with primary open-angle glaucoma (POAG) and of 481 normal subjects. The glaucoma groups did not differ in neuroretinal rim nor in perimetric mean defect. RESULTS: Mean optic disc area was significantly smaller in the pseudoexfoliative glaucoma eyes (2.54 +/- 0.51 mm2 vs. 2.71 +/- 0.63 mm2, p = 0.03) than in the primary open-angle glaucoma eyes. The pigmentary glaucoma group did not vary significantly from the primary open-angle glaucoma group in size of the optic disc. No significant differences were found for neuroretinal rim area, configuration of neuroretinal rim, depth of optic cup and diameters of the retinal arterioles and venules at the disc border between the secondary glaucoma groups and the POAG group respectively. Size of zone beta of the parapapillary atrophy was slightly, but not significantly smaller in the secondary glaucoma groups than in POAG. In the secondary glaucoma groups, the maximal intraocular pressure measurements were significantly (p < 0.001) higher than in the group with POAG. All glaucoma groups had a significantly smaller neuroretinal rim, significantly smaller retinal arterioles, and significantly larger parapapillary atrophy compared to the normal group. CONCLUSIONS: Except of a slightly smaller optic disc in eyes with pseudoexfoliative glaucoma, eyes with secondary glaucoma due to pseudoexfoliation or due to pigmentary dispersion do not vary significantly in their optic disc morphology compared to POAG and do not show pathognomonic features of the optic disc despite marked changes in the anterior segment of the eye.     

Associations between the deletion polymorphism of the angiotensin 1-converting enzyme gene and ocular signs of primary open-angle glaucoma

Background Primary open-angle glaucoma (POAG) is a leading cause of blindness. High intraocular pressure (IOP) has been shown to be a key risk factor for POAG. Topical application of angiotensin 1-converting enzyme (ACE) inhibitors has been shown to lower IOP, and angiotensin-induced increase in vascular tone has been implicated as a pathogenetic mechanism in glaucomatous cupping and damage to the optic nerve. The objective of this study was to investigate the association between the deletion polymorphism in the ACE gene and ocular signs of POAG.Methods Baseline data from the Rotterdam Study was used. The ACE genotype was determined in 6,462 subjects. We used univariate and multiple variable statistical techniques to examine associations between ACE genotype and each of ocular hypertension, glaucomatous optic neuropathy, glaucomatous visual field defects and POAG diagnosis.Results We found no consistent evidence between ACE genotype and ocular signs of POAG. We did, however, find evidence of an association between ACE genotype and optic disc area, subjects homozygous for the deletion allele tending to have fractionally smaller optic disc areas than those with a single deletion allele subjects, who in turn tended to have fractionally smaller optic discs than those with no deletion alleles (P=0.01)Conclusions The data provided little evidence of any association between ocular signs of POAG and the deletion polymorphism of ACE. There was, however, evidence that ACE may be associated with optic disc size—this was an unexpected finding.     

Impact of intraocular pressure after filtration surgery on visual field progression in primary open-angle glaucoma

PURPOSE: To compare visual field progression after trabeculectomy in eyes showing a postoperative intraocular pressure (IOP) less than or equal to 16 mmHg and eyes with an IOP of 17 to 21 mmHg. METHODS: A retrospective cohort study design was used. A total of 101 eyes of 101 consecutive patients undergoing trabeculectomy for primary open-angle glaucoma (POAG) with a postoperative IOP less than or equal to 21 mmHg were divided into two groups: Group 1 included eyes showing a postoperative IOP less than or equal to 16 mmHg at all visits and Group 2 included eyes with a postoperative IOP between 17 and 21 mmHg. In turn, each of these groups was divided into two subgroups according to whether treatment was required for IOP control. Glaucomatous visual field control during follow-up was compared between the subject groups. RESULTS: Kaplan-Meier analysis revealed glaucomatous visual field control in 98.53% of the eyes in Group 1 and 89.06% of those in Group 2 at 5 years, the difference between the groups being significant. CONCLUSIONS: Glaucomatous disease progression is less frequent when IOP is less than or equal to 16 mmHg in all the follow-up visits after trabeculectomy. The results indicate a definite benefit of low IOP in visual field control.     

Cup-to-disc ratio, intraocular pressure, and primary open-angle glaucoma in retinal venous occlusion

PURPOSE: To investigate the association of cup-to-disc ratio (CDR), intraocular pressure (IOP), and primary open-angle glaucoma (POAG) with the site of retinal venous occlusion (RVO) and optic nerve head swelling (ONHS). DESIGN: Prospective observational case series. PARTICIPANTS: Four hundred fifty consecutive cases from a single tertiary referral center. METHODS: Fundus photography of the retinopathy, 30 degrees stereo photography of the optic disc, and Goldmann applanation tonometry were the main parameters studied. The diagnosis of POAG was obtained from the referring ophthalmologist. MAIN OUTCOME MEASURES: The main outcome measures were the CDR, measured vertically through the center of the optic disc, and the site of RVO, identified as an arteriovenous (AV) crossing, optic cup, or optic nerve. Retinal venous occlusions occurring within the optic nerve were subdivided on the basis of the presence or absence of ONHS. RESULTS: There were poor correlations between CDR and IOP (r = 0.18; P = 0.000209) and CDR and age (r = 0.21; P = 0.000012). There were 197 AV crossing-sited RVOs (AV-RVOs) (43.8%) and 46 optic cup (OC)-sited RVOs (10.2%). The remainder occurred within the optic nerve; the ONHS group had 80 cases (17.8%) and the nonoptic nerve head swelling group (NONHS) had 127 cases (28.2%). The OC-RVO group tended to be the oldest of the four groups, whereas the ONHS group was the youngest (P < 0.000001). The mean CDR was significantly higher in the OC-RVO (0.65) compared with the rest of the groups (0.45-0.48). The proportion of cases with CDR > or = 0.7 was significantly higher in the OC-RVO group (39.1%) compared with the rest of the groups (0-6.3%). There was a trend (P = 0.000012) for IOP in the OC-RVO group (19.0 mmHg) and NONHS group (17.6 mmHg); the proportion of cases with IOP more than 21 mmHg was also higher in these cases (P = 0.00033). The prevalence of POAG was highest (P < 0.000001) in the OC-RVO group (39.1%) followed by the NONHS group (18.1%), ONHS group (8.8%), and AV-RVO (4.1%) group, respectively. CONCLUSIONS: Optic cup and optic nerve-sited RVO without ONHS are associated with raised IOP and may share a common management strategy aimed at controlling ocular pressure. Glaucomatous optic disc cupping, in contrast, seems to be important in the OC-sited RVO group only. Intraocular pressure, POAG, and glaucomatous optic disc cupping do not significantly seem to contribute to the development of RVO at an AV crossing or when the occlusion occurs within the optic nerve in association with ONHS.