Malignant glaucoma: a review of the modern literature.

Malignant glaucoma is a rare form of glaucoma that typically follows surgery in patients with primary angle closure and primary angle-closure glaucoma. In this paper, the clinical features, classification, pathogenesis, and principles of management are discussed. Despite a high prevalence of primary angle closure glaucoma in South-East Asia, the vast majority of cases of malignant glaucoma are reported in White populations. This may reflect differing mechanisms of angle closure in White and Asian patients, which somehow reduces the likelihood of an aberrant relationship developing between the lens, ciliary body, anterior hyaloid, and vitreous structures within the eye. Although the exact underlying pathogenic mechanism remains unclear, the prognosis is good with modern medical, laser, and surgical treatment modalities.

Trends in rates of trabeculectomy in England.

AIMS: Rates of glaucoma surgery have declined in North America and continental Europe in recent years. The aim of this study was to examine trends over time and regional variation in rates of trabeculectomy in England. METHODS: The hospital in-patient enquiry (HIPE), hospital episode statistics (HES), and the Oxford record linkage study (ORLS) were analysed for annual trabeculectomy admissions between 1976 and 2004. RESULTS: Annual rates of admission for trabeculectomy rose 10-fold from 1976 to 1995: from 3.7 (95% confidence intervals 3.5-3.9) admissions per 100,000 population in 1976 to a peak of 38.7 (38.1-39.3) in 1995. Admission rates then declined sharply and have begun to reach a plateau at around 10.6 (10.3-10.9) in 2004. The highest surgical rates during the period 1997-2004 were found in the 80- to 84-year-old age group. Geographical analysis showed wide variation across local authority areas in annual rates of trabeculectomy, from 4 (2.3-5.2) to 33 (29.0-36.5) people per 100,000 population in 1998-2004. The rate of surgery by local authority showed little or no association with the level of social deprivation in each area. CONCLUSIONS: The rate of patients undergoing trabeculectomy increased substantially over 20 years. This was followed by a profound reduction in rates of trabeculectomy from 1995, which coincides with the introduction of new topical medications to reduce intraocular pressure. Wide regional variation in rates of trabulectomy was found, but there was no evidence of reduced access to glaucoma surgery in deprived areas.

The role of scanning laser polarimetry using the GDx variable corneal compensator in the management of glaucoma suspects.

AIM: To determine the role of scanning laser polarimetry using the GDx variable corneal compensator (VCC) in the management of glaucoma suspects. METHODS: Over a 12-month period, 43 of 447 (9.6%) patients referred to a glaucoma screening clinic were classified as "glaucoma suspects" when it was not possible to categorise the optic disc appearance and visual fields as definitely glaucomatous or definitely normal. Of these patients, 39 underwent a full ophthalmic review, including assessment of the visual fields and analysis of the retinal nerve fibre layer with the GDx VCC. RESULTS: After the review, 17 of 39 (43.6%) patients were discharged because of normal GDx VCC results. The remaining 22 of 39 (56.4%) were considered to be at risk of developing progressive glaucoma, and further follow-up in the hospital eye service was recommended. 3 (7.7%) patients received treatment. Of the 22 patients, 12 were considered to have pre-perimetric normal tension glaucoma, 7 normal tension glaucoma and 1 primary open-angle glaucoma (POAG). In 19 of these patients, abnormal GDx VCC results were found, particularly inter-eye asymmetry in the nerve fibre layer thickness. However, in 2 of 39 (5.1%) patients the GDx VCC was normal, despite the presence of a neuroretinal rim defect in the optic disc with corresponding visual field loss, and in 1 patient with POAG. CONCLUSIONS: Scanning laser polarimetry using the GDx VCC is an important tool in defining the management strategies of glaucoma suspects. In screening for glaucoma, however, GDx VCC results should not be used in isolation, but in conjunction with conventional methods of optic disc and visual field assessment.

Direct costs of glaucoma and severity of the disease: a multinational long term study of resource utilisation in Europe.

BACKGROUND: Resource utilisation and direct costs associated with glaucoma progression in Europe are unknown. As population progressively ages, the economic impact of the disease will increase. METHODS: From a total of 1655 consecutive cases, the records of 194 patients were selected and stratified by disease severity. Record selection was based on diagnoses of primary open angle glaucoma, glaucoma suspect, ocular hypertension, or normal tension glaucoma; 5 years minimum follow up were required. Glaucoma severity was assessed using a six stage glaucoma staging system based on static threshold visual field parameters. Resource utilisation data were abstracted from the charts and unit costs were applied to estimate direct costs to the payer. Resource utilisation and estimated direct cost of treatment, per person year, were calculated. RESULTS: A statistically significant increasing linear trend (p = 0.018) in direct cost as disease severity worsened was demonstrated. The direct cost of treatment increased by an estimated 86 for each incremental step ranging from 455 euro per person year for stage 0 to 969 euro per person year for stage 4 disease. Medication costs ranged from 42% to 56% of total direct cost for all stages of disease. CONCLUSIONS: These results demonstrate for the first time in Europe that resource utilisation and direct medical costs of glaucoma management increase with worsening disease severity. Based on these findings, managing glaucoma and effectively delaying disease progression would be expected to significantly reduce the economic burden of this disease. These data are relevant to general practitioners and healthcare administrators who have a direct influence on the distribution of resources.

Outcomes of referrals by community optometrists to a hospital glaucoma service.

AIM: To determine the outcomes resulting from optometric referrals to a specialist glaucoma screening clinic over a 10 year period. METHODS: Details of the initial clinical assessment of all new patients referred to the adult glaucoma screening clinic at Oxford Eye Hospital were collected prospectively from July 1994 to June 2004. RESULTS: Optometrists working in community practice initiated 2505 referrals. Of these, glaucoma was confirmed in 510 patients (20.4%), including 160 with normal intraocular pressure (IOP). A diagnosis of ocular hypertension was made in 747 patients (29.8% of referrals) and 125 (5.0%) were categorised as glaucoma suspects. There was no evidence of a diagnostic trend over the period of data collection. Treatment to lower IOP was commenced in 458 patients (18.3%). Nearly half of those referred, 1148 (45.8%), were discharged from ophthalmological review at the first visit. CONCLUSION: In this survey, the largest of its nature, only one in five subjects had glaucoma and nearly half were discharged from hospital ophthalmological review. The findings provide a baseline against which the effectiveness of any future system of glaucoma detection in the United Kingdom can be compared.

Normal tension glaucoma is not associated with the common apolipoprotein E gene polymorphisms.

BACKGROUND: /aims: In normal tension glaucoma (NTG) factors other than raised intraocular pressure have a role in the pathogenesis of the optic neuropathy. Because particular apolipoprotein E (ApoE) gene polymorphisms have been associated with cell death and survival in neurological degenerative diseases, the purpose of this study was to determine the ApoE allele frequencies in patients with normal tension glaucoma. METHODS: The apolipoprotein E genotype of 155 patients with normal tension glaucoma was compared to that of 349 non-affected, control subjects from the same geographical area. A similar comparison was made between 53 patients with normal tension glaucoma who demonstrated progressive visual field loss, and control subjects. The frequencies of genotypes was compared with the chi(2) test and Mantel-Haenszel coefficent. RESULTS: There was no significant difference in the frequency of ApoE alleles or genotypes in the normal tension glaucoma population compared to the control group. The ApoE alleles and genotypes in NTG patients with progressive disease were not different from the control group. CONCLUSION: ApoE gene polymorphisms are not linked to normal tension glaucoma, suggesting that this gene does not have a role in the pathogenesis of optic neuropathy in this disease.

Long term effect on intraocular pressure of phacotrabeculectomy compared to trabeculectomy.

AIM: To compare the long term mean intraocular pressure (IOP) reduction after non-augmented single site phacotrabeculectomy with that after trabeculectomy and to determine the relation between preoperative IOP and IOP reduction. METHODS: A group of 44 consecutive patients with chronic open angle glaucoma who underwent phacotrabeculectomy were matched to a trabeculectomy control group and the results of surgery were compared. Linear regression analysis of preoperative IOP and IOP reduction was undertaken. RESULTS: The mean IOP reduction was significantly less in the phacotrabeculectomy group (6.7 (SD 2.1) mm Hg) than in the trabeculectomy group (11.0 (1.4) mm Hg) (p=0.0017). There was a significant difference in surgical success between the groups. The preoperative IOP was significantly related to the postoperative reduction in IOP in both groups (p<0.001). CONCLUSIONS: In elderly white patients with chronic open angle glaucoma, phacotrabeculectomy is not as effective as trabeculectomy in reducing IOP. In both procedures the magnitude of IOP reduction is proportional to the preoperative IOP.

The National Survey of Trabeculectomy. III. Early and late complications.

PURPOSE: There is a considerable body of literature relating to trabeculectomy, however there are no data representative of the national experience of trabeculectomy in the United Kingdom (UK). The Department of Health funded a national survey of trabeculectomy to establish current practice patterns and the outcome of trabeculectomy in the National Health Service (NHS). In this paper we present the reported complications of first-time trabeculectomy from a nationally representative cohort of patients with chronic open angle glaucoma. METHODS: Cross-sectional study of consultant ophthalmologists performing trabeculectomy in the NHS. Participants recruited their four most recent consecutive first-time trabeculectomy cases with chronic open angle glaucoma according to study eligibility criteria and data were collected by self-administered questionnaire. FOLLOW-UP: one year post-trabeculectomy. MAIN OUTCOME MEASURES: occurrence of early and late complications. RESULTS: Clinical outcome data were available for 1240 (85.3%) of cases. Early complications were reported in 578 (46.6%) cases and late complications in 512 (42.3%) cases. Some cases had more than one complication. The most frequent early complications were hyphaema (n = 304, 24.6%), shallow anterior chamber (n = 296, 23.9%), hypotony (n = 296, 24.3%), wound leak (n = 216, 17.8%) and choroidal detachment (n = 175, 14.1%). The most frequent late complications were cataract (n = 251, 20.2%), visual loss (n = 230, 18.8%) and encapsulated bleb (n = 42, 3.4%). The occurrence of most complications was not associated with a consultant's specialist interest, level of activity, type of hospital or region. Encapsulated bleb was reported more frequently in a university hospital setting. CONCLUSIONS: The complication rates reported in this paper represent the national experience of first-time trabeculectomy for open angle glaucoma in the UK. These are similar to previous published studies and highlight in particular, the impact of trabeculectomy on visual acuity in the first year following surgery. This survey provides valid and clinically relevant data on the complications of trabeculectomy for the production of guidelines and standards for audit at regional, local and individual level.

Periorbital dermatitis as a side effect of topical dorzolamide.

AIM: To report periorbital dermatitis as a late side effect of topical dorzolamide hydrochloride (Trusopt), a drug used to reduce intraocular pressure. METHODS: A retrospective study of 14 patients who developed periorbital dermatitis while using topical dorzolamide hydrochloride was undertaken. Six patients underwent patch testing for sensitivity to Trusopt, dorzolamide hydrochloride, and the preservative benzalkonium chloride. RESULTS: The periorbital dermatitis occurred after a mean period of 20.4 weeks of commencing dorzolamide hydrochloride therapy. 13 patients had used preserved topical beta blocker treatment for a mean period of 34.2 months without complication before the introduction of dorzolamide. In eight (57.1%) the dermatitis resolved completely after discontinuing dorzolamide but in six (42.9%) resolution of the dermatitis did not occur until the concomitant preserved beta blocker was stopped and substituted with preservative free drops. Patch testing for sensitivity to Trusopt, dorzolamide hydrochloride, and benzalkonium chloride was negative. CONCLUSION: These findings suggest that dorzolamide can cause severe periorbital dermatitis. Although the dermatitis may resolve when dorzolamide is discontinued, this does not always occur and in some patients all topical medication containing benzalkonium chloride needs to be stopped.

Combined surgery in the treatment of patients with cataract and primary open-angle glaucoma.

The literature on combined surgery in the treatment of patients with cataract and primary open-angle glaucoma was comprehensively studied, and all aspects and variations of the combined procedure were assessed. Phacoemulsification has improved the success rate and reduced the complication rate previously associated with extracapsular cataract extraction combined with trabeculectomy. A mean reduction in intraocular pressure (IOP) of 5 to 8 mm Hg can be achieved. One- and 2-site techniques appear to be similarly effective. Phacotrabeculectomy augmented with mitomycin-C achieves a lower IOP than phacotrabeculectomy alone but has a higher complication rate. The use of 5-fluorouracil is not as effective as mitomycin-C and has a variable influence on the results. The development of new techniques that combine nonpenetrating glaucoma surgery with phacoemulsification offers interesting surgical alternatives, but no long-term results have been reported.

Long term results and complications of trabeculectomy augmented with low dose mitomycin C in patients at risk for filtration failure.

AIM: To determine the results and complications up to 5 years after trabeculectomy with 0.02% mitomycin C (MMC) in glaucoma patients at risk for failure of filtration surgery. METHODS: A consecutive series of 21 eyes from 20 patients who underwent trabeculectomy with MMC 0.02%, with an exposure time of 2 minutes, was retrospectively analysed and the results were compared with previously published data. RESULTS: The mean preoperative intraocular pressure (IOP) was 28 mm Hg on an average of 2.8 glaucoma medications, and the mean postoperative IOP after 3 years was 14 mm Hg on an average of 0.4 medications. Three years after trabeculectomy, 17 of 21 (80.9%) eyes had an IOP of less than 21 mm Hg without medical treatment. Using Kaplan-Meier life table analysis the 5 year probability of an IOP less than 21 mm Hg without medication was 67% and with medication was 90%. Two patients required further glaucoma surgery during the first postoperative year, and another developed hypotonous maculopathy which was reversed after bleb revision. Seven patients developed visually significant cataract as a late consequence of the surgery. There were no bleb related infections. CONCLUSION: In the long term MMC 0.02% used for 2 minutes intraoperatively is an effective adjunctive treatment in glaucoma patients at risk for bleb failure and in this dose is associated with few complications.

Trabeculectomy with mitomycin C in the treatment of post-traumatic angle recession glaucoma.

AIM: The presence of traumatic angle recession is a risk factor for failure of glaucoma filtration surgery and a previous study has suggested that antimetabolite treatment should be used in these patients. This study was undertaken to determine for the first time the mid term results of trabeculectomy with intraoperative application of mitomycin C in patients with post-traumatic angle recession glaucoma. METHODS: A retrospective analysis was made of 43 consecutive trabeculectomy procedures in 41 young black/mixed race patients followed for a mean period of 25 months (range 2-66 months). Mitomycin C 0.02% was applied between the sclera and conjunctiva for 1-5 minutes at the time of surgery. The intraocular pressure and visual acuity were measured postoperatively. The success of this technique was analysed by using a Kaplan-Meier cumulative survival curve. RESULTS: The intraocular pressure was successfully controlled at last follow up without topical treatment in 77% (33/43 eyes) and the visual acuity was the same or better in 81% (35/43 eyes). Cumulative probability of success was 85% at 1 year follow up, 81% at 2 years, and 66% at 3 years and thereafter. Hypotonous maculopathy occurred in one patient and no cases of late bleb infection were found. CONCLUSIONS: In medically uncontrolled post-traumatic angle recession glaucoma trabeculectomy with mitomycin C is an effective surgical procedure with an acceptable complication rate. Good intraocular pressure control and preservation of vision can be expected in most patients.

The National Survey of Trabeculectomy. II. Variations in operative technique and outcome.

PURPOSE: There is a considerable body of literature relating to trabeculectomy; however, there are no data representative of the national experience of trabeculectomy in the United Kingdom (UK). The Department of Health funded a national survey of trabeculectomy to establish current practice patterns and the outcome of trabeculectomy in the National Health Service (NHS). In this paper we report variations in surgical technique and the national success rate of trabeculectomy. METHODS: A cross-sectional survey was carried out of consultant ophthalmologists performing trabeculectomy in the NHS. Participants recruited their four most recent consecutive first-time trabeculectomy cases according to study eligibility criteria and data were collected by self-administered questionnaire. FOLLOW-UP: 1 year post-trabeculectomy. Main outcome measure of success: final intraocular pressure (IOP) less than two-thirds the pre-operative IOP. Secondary outcome measures of success: final IOP less than 21 mmHg and visual field stability. Success was further defined as unqualified (excluding patients on anti-glaucoma medications at final follow-up) or qualified (including patients on anti-glaucoma medications at final follow-up). The relationship between variables characterising consultants' practice and main outcome measure was examined by chi-square test. RESULTS: Clinical outcome data were available for 1240 (85.3%) cases. There were wide variations in operative technique. The mean post-operative IOP was 14.4 mmHg (95% CI 14.2-14.7), which is a mean reduction of 11.8 mmHg (95% CI 11.4-12.2). An unqualified success, in terms of the main outcome measure, was achieved in 66.6% of patients and a qualified success in 71.0% of cases. An unqualified success, in terms of a final IOP less than 21 mmHg, was achieved in 84.0% of cases and a qualified success in 92.0%. Visual fields were stable in 84.2%. Outcome was not related to consultants' specialist interest, level of activity, type of hospital or region. CONCLUSIONS: The success rates reported in this paper represent the national experience of first-time trabeculectomy for open angle glaucoma in the UK. The national success rate at 1 year compares favourably with many studies in the literature. This survey provides valid and clinically relevant measures of success for the production of guidelines and standards for audit at regional, local and individual level and a baseline for the comparison of new therapies.

Anterior uveitis as a side effect of topical brimonidine.

PURPOSE: To report anterior uveitis as a late side-effect of topical brimonidine tartrate 0.2% (Alphagan; Allergan Inc., Irvine, California). METHODS: Four patients aged 79 to 91 (mean, 83) years, who developed acute anterior uveitis while using topical brimonidine for chronic glaucoma, were clinically evaluated for causes of uveitis. When the inflammation had completely cleared, topical brimonidine was recommenced in one eye only to determine causality. RESULTS: All four patients developed acute granulomatous anterior uveitis, which resolved rapidly on stopping brimonidine and receiving treatment with topical corticosteroids. The uveitis occurred 11 to 15 (mean, 13.8) months after commencement of brimonidine 0.2% twice daily. None of the patients had a previous history of uveitis, and no other identifiable cause of uveitis was found. In all patients, on rechallenge with brimonidine instilled twice daily to one eye, uveitis recurred within 3 weeks in that eye only. CONCLUSIONS: These findings suggest that brimonidine can cause anterior uveitis as a late side effect. The inflammation settles rapidly on stopping the medication and on using topical corticosteroids and recurs on rechallenge with brimonidine.