Performance characteristics of multicolor versus blue light and infrared imaging in the identification of reticular pseudodrusen

Abstract

AbstractPurpose To describe the appearance of reticular pseudodrusen (RPD) on multicolor imaging (MC) and to evaluate its diagnostic accuracy as compared with the two modalities considered the current reference standard, blue light (BL) and infrared (IR).Methods A retrospective study reviewing all multicolor images of a series of consecutive patients. Inclusion criteria involved the presence of > 1 RPD on a 30º x 30º image centered on the fovea as seen with the BL channel derived from the multicolor imaging of the Spectralis HRA+OCT ®. The diagnosis of RPD was confirmed by the identification of subretinal debris on a tracking‐assisted SD OCT Heidelberg. A 3.0 mm diameter circle divided in 4 fields (S, N, I and T) was overlaid on each image and manually centered on the foveola. Three experienced observers, masked to their own results with other imaging modalities, independently classified the number of RPD in each field in each image with each modality, according to this classification: Category 0: 0‐5 RPD ; 1: 6‐20; 2: 21‐35; 3: 36‐49; and 4: >50. Friedman and Wilcoxon tests were used for the comparison between different imaging modalities per field by the same observer. The kappa (K) coefficient was used to measure interobserver agreementResults MC and IR modalities showed higher sensitivity and interobserver agreement in RPD detection than BL. No clinically significant differences were found between multicolor and IR.Conclusion Multicolor imaging modality (the new index test) can play an important role in the identification, quantification and categorization of RPD when compared to the reference standard test (images of BL and IR), a result which is still the subject of much debate.