Subtypes of Primary Angle Closure Disease Based on Age-independent Anterior Segment Optical Coherence Tomography Parameters

Overview

Journal Eye (Lond)

Date 2025 Feb 7

PMID 39920346

Authors

Ruthra Umapathi

Marco Yu

Ching-Yu Cheng

Raymond P Najjar

Rahat Husain

Ching Lin Ho

Tina T Wong

Pui Yi Boey

Shamira Perera

Eranga N Vithana

Tin Aung

Monisha E Nongpiur

Affiliations

Soon will be listed here.

Abstract

Objective: To identify subgroups of angle closure disease by considering age-independent anterior segment parameters.

Methods: Anterior-segment optical coherence tomography (ASOCT) was performed in primary angle closure suspect (PACS) and primary angle closure glaucoma (PACG) patients. Clustering analysis using age-independent parameters, anterior chamber width (ACW), anterior vault (AV), posterior corneal arc length (PCAL), and iris area was performed. The optimum number of subgroups was determined using Bayesian Information Criterion and subjects were classified into subgroups by Gaussian Mixture Model methods.

Results: A total of 650 PACS and 411 PACG were analysed. The optimal number of subgroups of the combined PACS and PACG dataset was 3. Subgroup 1 (n = 186, 29.3%) has the largest anterior chamber dimension with large AV and total anterior chamber area, subgroup 2 (n = 16, 2.5%) has the widest ACW and shallowest anterior chamber depth (ACD), and subgroup 3 (n = 432; 68.1%) has large iris area with the smallest anterior chamber dimensions, characterised by a small ACW, AV, and PCAL. Subgroup 3 comprised a significantly greater proportion of PACG compared to PACS (74.2% vs 64.6%, p = 0.04) while subgroup 1 had the greatest proportion of PACS ≥ 70 years old, yet to have progressed to PACG.

Conclusion: We identified 3 subgroups of angle closure eyes, each characterised by distinct structural components based on ASOCT. A greater proportion of older PACS yet to have progressed to PACG belonging to the subgroup with the largest anterior chamber dimensions suggests that a more spacious anterior chamber may be associated with PACS that remains stable.

References

George R, Panda S, Vijaya L . Blindness in glaucoma: primary open-angle glaucoma versus primary angle-closure glaucoma-a meta-analysis. Eye (Lond). 2021; 36(11):2099-2105. PMC: 9582001. DOI: 10.1038/s41433-021-01802-9. View

Quigley H, Broman A . The number of people with glaucoma worldwide in 2010 and 2020. Br J Ophthalmol. 2006; 90(3):262-7. PMC: 1856963. DOI: 10.1136/bjo.2005.081224. View

He M, Jiang Y, Huang S, Chang D, Munoz B, Aung T . Laser peripheral iridotomy for the prevention of angle closure: a single-centre, randomised controlled trial. Lancet. 2019; 393(10181):1609-1618. DOI: 10.1016/S0140-6736(18)32607-2. View

Baskaran M, Kumar R, Friedman D, Lu Q, Wong H, Chew P . The Singapore Asymptomatic Narrow Angles Laser Iridotomy Study: Five-Year Results of a Randomized Controlled Trial. Ophthalmology. 2021; 129(2):147-158. DOI: 10.1016/j.ophtha.2021.08.017. View

Nongpiur M, Gong T, Lee H, Perera S, Cheng L, Foo L . Subgrouping of primary angle-closure suspects based on anterior segment optical coherence tomography parameters. Ophthalmology. 2013; 120(12):2525-2531. DOI: 10.1016/j.ophtha.2013.05.028. View

Nongpiur M, Atalay E, Gong T, Loh M, Lee H, He M . Anterior segment imaging-based subdivision of subjects with primary angle-closure glaucoma. Eye (Lond). 2016; 31(4):572-577. PMC: 5395994. DOI: 10.1038/eye.2016.267. View

Moghimi S, Torkashvand A, Mohammadi M, Yaseri M, Saunders L, Lin S . Classification of primary angle closure spectrum with hierarchical cluster analysis. PLoS One. 2018; 13(7):e0199157. PMC: 6056027. DOI: 10.1371/journal.pone.0199157. View

Li M, Chen Y, Chen X, Zhu W, Chen X, Wang X . Differences between fellow eyes of acute and chronic primary angle closure (glaucoma): An ultrasound biomicroscopy quantitative study. PLoS One. 2018; 13(2):e0193006. PMC: 5814014. DOI: 10.1371/journal.pone.0193006. View

Foster P, Buhrmann R, Quigley H, Johnson G . The definition and classification of glaucoma in prevalence surveys. Br J Ophthalmol. 2002; 86(2):238-42. PMC: 1771026. DOI: 10.1136/bjo.86.2.238. View

10.

Console J, Sakata L, Aung T, Friedman D, He M . Quantitative analysis of anterior segment optical coherence tomography images: the Zhongshan Angle Assessment Program. Br J Ophthalmol. 2008; 92(12):1612-6. DOI: 10.1136/bjo.2007.129932. View

11.

Nongpiur M, Sakata L, Friedman D, He M, Chan Y, Lavanya R . Novel association of smaller anterior chamber width with angle closure in Singaporeans. Ophthalmology. 2010; 117(10):1967-73. DOI: 10.1016/j.ophtha.2010.02.007. View

12.

Nongpiur M, He M, Amerasinghe N, Friedman D, Tay W, Baskaran M . Lens vault, thickness, and position in Chinese subjects with angle closure. Ophthalmology. 2010; 118(3):474-9. DOI: 10.1016/j.ophtha.2010.07.025. View

13.

Wu R, Nongpiur M, He M, Sakata L, Friedman D, Chan Y . Association of narrow angles with anterior chamber area and volume measured with anterior-segment optical coherence tomography. Arch Ophthalmol. 2011; 129(5):569-74. DOI: 10.1001/archophthalmol.2011.68. View

14.

Wang B, Sakata L, Friedman D, Chan Y, He M, Lavanya R . Quantitative iris parameters and association with narrow angles. Ophthalmology. 2009; 117(1):11-7. DOI: 10.1016/j.ophtha.2009.06.017. View

15.

Kruppa J, Liu Y, Diener H, Holste T, Weimar C, Konig I . Probability estimation with machine learning methods for dichotomous and multicategory outcome: applications. Biom J. 2014; 56(4):564-83. DOI: 10.1002/bimj.201300077. View

16.

How A, Baskaran M, Kumar R, He M, Foster P, Lavanya R . Changes in anterior segment morphology after laser peripheral iridotomy: an anterior segment optical coherence tomography study. Ophthalmology. 2012; 119(7):1383-7. DOI: 10.1016/j.ophtha.2012.01.019. View

17.

Ang B, Nongpiur M, Aung T, Mizoguchi T, Ozaki M . Changes in Japanese eyes after laser peripheral iridotomy: an anterior segment optical coherence tomography study. Clin Exp Ophthalmol. 2015; 44(3):159-65. DOI: 10.1111/ceo.12673. View

18.

Chen X, Wang X, Tang Y, Sun X, Chen Y . Optical coherence tomography analysis of anterior segment parameters before and after laser peripheral iridotomy in primary angle-closure suspects by using CASIA2. BMC Ophthalmol. 2022; 22(1):144. PMC: 8962180. DOI: 10.1186/s12886-022-02366-2. View

19.

Xu B, Friedman D, Foster P, Jiang Y, Porporato N, Pardeshi A . Ocular Biometric Risk Factors for Progression of Primary Angle Closure Disease: The Zhongshan Angle Closure Prevention Trial. Ophthalmology. 2021; 129(3):267-275. PMC: 8863620. DOI: 10.1016/j.ophtha.2021.10.003. View

20.

Weinreb R, Aung T, Medeiros F . The pathophysiology and treatment of glaucoma: a review. JAMA. 2014; 311(18):1901-11. PMC: 4523637. DOI: 10.1001/jama.2014.3192. View