For patients with early or intermediate AMD, retromode imaging deviated to the right and left may be a potential supplementary tool to detect very small drusen, a study in Ophthalmology Retina suggests. The team of researchers also report near-infrared reflectance and green fundus autofluorescence did well in classifying dot subretinal drusenoid deposits, while confocal pseudocolor was optimal in characterizing ribbon subretinal drusenoid deposits.

The study enrolled 100 eyes of patients with early or intermediate AMD who underwent a complete multimodal imaging assessment with a confocal scanning laser ophthalmoscope, including near-infrared reflectance, green fundus autofluorescence, confocal pseudocolor and retromode imaging deviated to the right and left. The researchers topographically divided drusen as small and medium (≤125μ diameter) and large (>125μ diameter), and subretinal drusen deposits were divided into dot and ribbon phenotypes.

For each imaging modality, the reliability ranged between 0.81 and 0.98 between two readers.

Overall, the study found large drusen were better identified with confocal pseudocolor imaging (96.6% sensitivity; 77.8% specificity), while smaller drusen were better detected with retromode modalities either deviated to the right or left (92% sensitivity; 85.2% specificity, and 58.3% sensitivity; 83.3% specificity, respectively). Color imaging best detected ribbon subretinal drusenoid deposits (80.5% sensitivity; 98.4% specificity). Dot subretinal drusenoid deposits were well identified with near-infrared reflectance (83.1% sensitivity; 91.4% specificity) and green fundus autofluorescence (83.1% sensitivity; 91.4% specificity).

Cozzi M, Monteduro D, Parruli S, et al. Sensitivity and specificity of multimodal imaging in characterizing drusen. Ophthalmology Retina. April 23, 2020. [Epub ahead of print].