Identification of amblyogenic risk factors with the Brückner reflex test using the low-cost Arclight direct ophthalmoscope.

Background/objectives: The Arclight is a novel, low-cost, solar-powered direct ophthalmoscope developed for low resource settings as an alternative to more expensive, conventional devices. The Brückner reflex test (BRT) is a quick and effective means to screen for eye disease and amblyogenic risk factors. This test is however rarely performed in low resource settings due to the lack of access to ophthalmoscopes and trained health care workers. Our aim was to establish the sensitivity and specificity of the BRT when performed by a non-expert using an Arclight and compare to an expert as well as the results of a full clinic workup.

Subjects/methods: In this prospective, blinded study, 64 patients referred to a paediatric ophthalmology clinic had the BRT performed by a 'non-expert' observer (medical student) then an 'expert' observer (consultant ophthalmologist). These results were then compared against the 'gold standard' outcomes of a full clinical workup.

Results: BRT screening by the expert observer led to a sensitivity of 75.0% [95% CI: 57.9-86.8%] and a specificity of 90.6% [95% CI: 75.8-96.8%] in picking up media opacity, strabismus, refractive error or a combination of the above. For the non-expert, the sensitivity and specificity were 71.9% [95% CI: 54.6-84.4%] and 84.4% [95% CI: 68.3-93.1%], respectively.

Conclusions: The Arclight can be effectively used to perform the BRT and identify eye disease and common amblyogenic risk factors. Even when performed by a non-expert the results are highly specific and moderately sensitive. This study consequently offers support for the use of this low-cost ophthalmoscope in the expansion of eye screening by health care workers in low resource settings.