Amsler grid sensitivity levels in the diagnosis of neovascular age-related macular degeneration (AMD) are approximately 67% — lower than is typically recommended for detecting disease progression, according to a study recently published in JAMA Ophthalmology. Researchers suggest that patients continue to be seen in ophthalmology offices, regardless of the results of home Amsler grid testing.
The researchers conducted systematic review and meta-analysis of the diagnostic test accuracy (sensitivity and specificity) of the Amsler grid in the diagnosis of neovascular AMD. The team conducted a systematic literature search for relevant publication from database inception until May 7, 2022 and included studies with groups defined as having neovascular AMD and either healthy eyes or eyes with non-neovascular AMD. The index test was the Amsler grid, and the reference standard was ophthalmic examination.
The researchers identified 10 studies into Amsler grid sensitivity and diagnostic accuracy that met the inclusion criteria. These studies included a total of 1890 eyes (range of mean participant age, 62–83 years).
The team found the Amsler grid sensitivity and specificity to diagnose neovascular AMD were 67% (95% confidence interval [CI], 51-79) and 99% (95% CI, 85-100), respectively, when the comparator population were healthy control participants and 71% (95% CI, 60-80) and 63% (95% CI, 49-51), respectively, when the comparator population were patients with non-neovascular AMD.
“In conclusion, our findings suggest that the Amsler grid test should be used with caution for detecting neovascular AMD in eyes with an a priori risk of neovascular AMD,” concluded the researchers. “Thus, physicians recommending the Amsler grid self-assessment should also encourage patients to undergo ophthalmic examination regularly, regardless of Amsler grid results.”
The researchers also refer to a post hoc analysis that shows Amsler grid sensitivity is higher for classic choroidal neovascularization (CNV) than occult CNV, speculating that the finding could indicate the sensitivity for nonexudative CNV is likely similar to that of occult CNV.
Limitations of the study included the retrospective design, widespread adoption of OCT in clinical practice during the study period, performance of a supervised Amsler grid test, and different distributions of CNV subtypes across studies.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Bjerager J, Schneider M, Potapenko I, et al. Diagnostic accuracy of the Amsler grid test for detecting neovascular age-related macular degeneration: a systematic review and meta-analysis. JAMA Ophthalmol. Published online February 16, 2023. doi:10.1001/jamaophthalmol.2022.6396