Defining "occludable" angles in population surveys: drainage angle width, peripheral anterior synechiae, and glaucomatous optic neuropathy in east Asian people

Foster, Paul J.; Aung, Tin; Nolan, Winifred; Machin, David; Baasanhu, Jamyanjav; Khaw, PT; Alsbirk, P-H; Lee, P S; Seah, S.K.W.; Johnson, Gordon J.

doi:10.1136/bjo.2003.020016

Cited by 118 publications

(89 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Narrower angles are more likely to close than wider angles. 16 The likelihood of satisfactorily controlling IOP is inversely related to the circumference of trabecular meshwork affected by peripheral anterior synechiae (PAS). 17,18 Categorizing the stage of disease does not identify the mechanism causing the angle to close.…”

Section: Definition and Classificationmentioning

confidence: 99%

“…[45][46][47] These gonioscopic grades provide an index of the likelihood of closure. 16 A dichotomous classification of drainage angle width (and perceived risk of closure) is used in epidemiological research. Angles have been termed 'occludable' or 'not occludable' based on the visibility of the posterior trabecular meshwork in the static gonioscopy.…”

Section: Gonioscopymentioning

confidence: 99%

See 1 more Smart Citation

Angle-closure glaucoma in East Asian and European people. Different diseases?

Foster

Johnson

et al. 2005

Eye

Self Cite

177

102

View full text Add to dashboard Cite

In contrast to the pattern of disease in Europeans, primary angle closure has a higher prevalence and tends to be asymptomatic in East Asians. The higher prevalence is attributed to differences in anterior chamber and angle anatomy. Several studies suggest that central anterior chamber depth is shallower in East Asians than in Europeans, although this is not universally accepted. It is debated whether pupil block is the predominant mechanism of angle closure in Asian people. Meaningful comparison between studies is currently hindered by differences in patient selection, examination technique, and case definition; however, the major scientific deficiency is the paucity of prospective followup data to give an insight into natural history of the disease. This review examines the data on prevalence, risk factors, and mechanism of angle closure. Special consideration is given to limitations of methodology in research to date, with the intention of developing more robust data in future studies.

show abstract

Section: Definition and Classificationmentioning

confidence: 99%

Section: Gonioscopymentioning

confidence: 99%

Angle-closure glaucoma in East Asian and European people. Different diseases?

Foster

Johnson

et al. 2005

Eye

Self Cite

177

102

View full text Add to dashboard Cite

show abstract

“…No patient developed any of the complications previously reported with surgical goniosynechialysis. 1,7 The authors suggest that the possible mechanism of action of VGP is stretching and breaking PAS thereby widening of the angle recess and flattening of the angle. Undoubtedly, the patients in this study had a mix of phacomorphic and synaechial closure, which can be difficult to differentiate in ACAG eyes.…”

Section: Discussionmentioning

confidence: 99%

“…In some cases, permanent peripheral anterior synechiae (PAS) develop and, when greater than 1801 of the angle is closed, the IOP rises despite medical therapy or patent PI. 1 Various glaucoma operations 2 have been advocated to open the angle in such patients with refractory ACAG. However, these interventions can be associated with serious side effects resulting in long-term visual deterioration.…”

Section: Introductionmentioning

confidence: 99%

Viscogonioplasty: an effective procedure for lowering intraocular pressure in primary angle closure glaucoma

Varma

Baylis

Wride

et al. 2006

Eye

View full text Add to dashboard Cite

Purpose To evaluate the safety and intraocular pressure (IOP) lowering effect of combined phacoemulsification and viscogonioplasty (Phaco-VGP) in managing primary acute closed-angle glaucoma (ACAG) unresponsive to conventional therapy (patent PI). Patient and Methods In all, 15 consecutive eyes of patients with refractory ACAG and greater than 2701 peripheral anterior synechiae (PAS) underwent VGP. The technique of VGP involved routine phacoemulsification with intraocular lens implantation (Phaco/IOL) under topical anaesthetic. Following IOL implantation a heavy viscoelastic was used to deepen the anterior chamber and then injected near the angle for 3601 (without touching the trabecular meshwork) to break the PAS. No surgical instrument was used to physically break the PAS. Upon completion of VGP, automated irrigation with balanced salt solution to remove the viscoelastic was performed. Results Mean IOP reduced from 52.1 to 14.1 mmHg by Phaco-VGP at 6-months review. 14/15 patients were free of glaucoma medications at 6-month review. All angles showed exposure of the trabecular meshwork over 3601 postoperatively without evidence of residual synechiae. No untoward complications were observed in any patient. Conclusion VGP may have a role in controlling IOP effectively and safely in patients with refractory ACAG. It produces a large drop in the IOP and opening of the angle. It is a relatively simple technique to learn and we would recommend its use in the eyes of all patients who have had ACAG and are undergoing cataract extraction.

show abstract

“…3 The ultimate challenge will be to assimilate the static features that Spaeth highlights into a comprehensive, dynamic model of the determinants of iridotrabecular contact, which is validated in longitudinal studies of incident angle-closure and glaucomatous optic neuropathy. The articles by Halberstadt et al, 1 Taner et al, 2 and Loukovaara et al 3 illustrate systemic errors in statistical analysis. They use two-sample t-tests or analysis of variance (ANOVA), but ignore their shortcomings.…”

mentioning

confidence: 99%

Angle-closure glaucoma in East Asian and European people. Different diseases?

Spaeth¹

2006

Eye

View full text Add to dashboard Cite

Defining "occludable" angles in population surveys: drainage angle width, peripheral anterior synechiae, and glaucomatous optic neuropathy in east Asian people

Cited by 118 publications

References 12 publications

Angle-closure glaucoma in East Asian and European people. Different diseases?

Angle-closure glaucoma in East Asian and European people. Different diseases?

Viscogonioplasty: an effective procedure for lowering intraocular pressure in primary angle closure glaucoma

Angle-closure glaucoma in East Asian and European people. Different diseases?

Contact Info

Product

Resources

About