Combined structure–function analysis in glaucoma screening

Abstract

AimTo assess the applicability of a structure–function (S-F) analysis combining spectral-domain optical coherence tomography (SD-OCT) and standard automated perimetry (SAP) in glaucoma screening in a middle-aged population.MethodsA randomised sample of 3001 Caucasian participants aged 45–49 years of the Northern Finland Birth Cohort Eye Study was examined. We performed an eye examination, including 24–2 SAP, optic nerve head (ONH) and retinal nerve fibre layer (RNFL) photography and SD-OCT of the peripapillary RNFL. The S-F report was generated by Forum Glaucoma Workplace software. OCT, SAP and the S-F analysis were evaluated against clinical glaucoma diagnosis, that is, the positive ‘2 out of 3’ rule based on the clinician’s evaluation of ONH and RNFL photographs and visual fields (VFs).ResultsAt a specificity of 97.5%, the sensitivity for glaucomatous damage was 26% for abnormal OCT, 35% for SAP and 44% for S-F analysis. Estimated areas under the curve were 0.74, 0.85 and 0.76, and the corresponding positive predictive values were 8 %, 10% and 12%, respectively. By applying a classification tree approach combining OCT, SAP and defect localisation data, a sensitivity of 77% was achieved at 90% specificity. In a localisation analysis of glaucomatous structural and functional defects, the correlation with glaucoma increased significantly if the abnormal VF test points were located on borderline or abnormal OCT zones.ConclusionSAP performs slightly better than OCT in glaucoma screening of middle-aged population. However, the diagnostic capability can be improved by S-F analysis.

Morphology of the optic nerve head and factors affecting it in the Northern Finland birth cohort

“…To our knowledge, our study is the first to explore potential factors affecting the six RNFL zones used in the S–F analysis. Identifying factors that affect the zones could improve the performance of the S–F analysis that has been shown to produce variable results in screening and diagnosing glaucoma (Karvonen et al, 2021; Nilforushan et al, 2012; Wu et al, 2015).…”

“…Automatically generated structure-function analysis (S-F analysis) can be used for glaucoma diagnostics and follow-up. Karvonen et al studied this as a potential method for systematic glaucoma screening (Karvonen et al, 2021). However, the potential factors affecting the six peripapillary RNFL zones used in the S-F analysis are what is not yet known (Figure 1).…”

The Finnish current care guideline for open‐angle glaucoma

“…give different results in glaucoma diagnostics and progression analysis (Azuara-Blanco et al, 2016;Caprioli et al, 1996;Karvonen et al, 2022;Leaney et al, 2012;Quigley et al, 1992) Caprioli et al, 1996;Girkin, 2000;Katz et al, 1997;Leaney et al, 2012;Quigley et al, 1992).…”

“…• During follow-up, structural and functional defects typically occur and progress at different rates. The delay from structural to functional damage can be up to several years (Karvonen et al, 2022;Leaney et al, 2012;Quigley et al, 1992).…”

“…￮ Also, there may be a high risk of bias in the published studies. Caprioli et al, 1996;Karvonen et al, 2022;Zhu et al, 2010). • The following evidence is available regarding the application of different test methods and the need for method combining: ￮ No single parameter of the optic disc (e.g.…”