Study Articulates Ocular Biometrics that Signify Risk of Early-onset Angle Closure, Glaucoma

Possible mechanisms for primary angle closure in young patients may be pseudoplateau iris configuration, plateau iris configuration, relative pupillary block and exaggerated lens vault, in that order. Photo: Howell Findley, OD. Click image to enlarge. Primarily, eye doctors, and physicians in general, don’t associate glaucoma with younger patients. However, early-onset primary angle closure disease (EOPACD) affects, by definition, individuals under the age of 40 and, since it is a more unusual condition for the age, prompt detection is paramount to get these patients proper treatment. This is especially important since some evidence has found angle closure glaucoma in such patients can have no overt ocular anomalies.A newly published study, appearing in the journal Eye, attempted to identify which possible biometric associations may exist in those with early-onset angle closure and their relevant cutoffs to properly distinguish glaucomatous eyes from suspects. Included in the investigation were 190 eyes with EOPACD (128 patients) aged 20 to 40; mean age was 34.2 years. Three groups were stratified from such patients: early-onset primary angle closure suspect (EOPACS), early-onset primary angle closure (EOPAC) and early-onset primary angle closure glaucoma (EOPACG).After conducting gonioscopy, ultrasound biomicroscopy, anterior segment OCT and optical biometry, the study researchers found that axial length was the shortest, while anterior chamber depth (ACD), anterior chamber area and angle parameters on OCT were narrowest in glaucomatous eyes when compared with suspects and EOPAC. Glaucomatous eyes also exhibited the highest measurements for lens vault and lens thickness. Even further, analysis revealed that ACD possessed the highest predictive ability, followed by lens thickness and anterior chamber area for angle closure glaucoma. The fourth strongest biometric risk factor was lens vault, and axial length was found to be a poor predictor.With ACD, a measurement of ≤2.73mm represented a ~4.5 times greater risk to eyes for developing glaucoma, and a progressively shallower anterior chamber was seen with increased severity of disease. As the authors explain, this observation was similar to previous reports showing that late-onset PACG eyes had shallow ACD linked with heightened angle closure glaucoma risk.Anterior chamber area was also found to be smaller in eyes that already developed glaucoma, with a cutoff of <17.24mm2 possessing the highest sensitivity for identifying at-risk eyes. What’s more, anterior chamber width in eyes with angle closure glaucoma was smaller than in the other two study groups—this difference was statistically significant when comparing glaucoma with suspects. Thus, the authors argue, “anterior chamber crowding is the single-most important determinant for association with glaucoma, irrespective of age and ethnicity.”The second highest predictive ability was lens thickness, with an anteriorly positioned, thickened lens seen in younger patients that is also seen with late-onset PACD. Specifically, a lens thickness of ≥4.22mm represented a ~4 times higher risk, and a lens vault ≥0.65mm mapped onto a 2.3 times higher risk for having glaucoma. Prior studies have reported that other than thicker lenses, anteriorly placed ones are also a predisposing factor for early-onset angle-closure disease. The authors of the current study concur that this makes sense, adding that a higher lens vault and anteriorly placed lens are linked to more anterior chamber crowding and anterior iris displacement, resulting in increased irido-lenticular contact. Due to these reasons, the authors believe “these findings indicate lens-based surgical methods as possible therapeutic procedures for IOP control, even in EOPACD eyes.”Click here for the journal source. Gupta S, Yadav SK, Panigrahi A, et al. Risk factor stratification in early-onset primary angle closure disease. Eye (Lond). July 18, 2025. [Epub ahead of print]. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.