Abstract
Purpose :
We performed a clinical prospective observational study to evaluate the visualization of different types of drusen and subretinal drusenoid deposits (SDD) by multimodal imaging and to assess sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of retromode imaging and color fundus images
Methods :
38 eyes of 31 consecutive patients, mean age 78.8 (SD 7.0), with different types of drusen or subretinal drusenoid deposits, were examined by Nidek Mirante (Nidek, Gamagori, Japan), a prototype confocal scanning laser ophthalmoscope. Presence of atrophy or choroidal neovascularization were considered as exclusion criteria.
Retromode imaging uses a laterally deviated confocal aperture with a central stop instead of a conventional confocal aperture, that allows to obtain pseudo-three-dimensional images of deeper retinal layers. Two different retromode images per eye were obtained via two confocal apertures, which were deviated to the right (“DR” mode) or left sides (“DL” mode).
All patients underwent a complete multimodal imaging assessment, including infrared reflectance, fundus autofluorescence, real confocal color fundus image (RCC), retromode imaging (DR and DL) and optical coherence tomography.
Two masked retinal graders independently evaluated each image in random fashion classifying drusen as soft drusen, cuticular drusen, ribbon SDD and dot SDD.
Results :
We found soft drusen in 76.3% of the eyes, cuticular drusen in 84.2%, ribbon SDD in 44.7% and dot SDD in 63.2%.
Sensitivity, specificity, PPV, NPV and accuracy for each modality are shown in table 1.
In DR mode, cuticular and soft drusen appear as tiny and wide depression, respectively. In DL mode, they appear as mounds of different size.
Ribbon SDD are well identified with both modalities and show classic reticular pattern.
Although DR mode appears to barely differentiate dot SDD to cuticular drusen, DL modality shows a more precise identification of both entities.
In conclusion, RCC seems to be more meticulous in detecting soft drusen and ribbon SDD.
Conclusions :
Retromode imaging is a non-invasive diagnostic technique which is useful in identifying different types of drusen and subretinal drusenoid deposits. Alongside current imaging modalities, retromode imaging may serve as a useful supplementary tool in a multimodal imaging approach.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.