Purpose:
To describe the near-infrared autofluorescence (NIA) findings in reticular pseudodrusen (RPD) and to characterize the lesions using a point-by-point comparison of the lesions on optical coherence tomography (OCT), infrared reflectance imaging (IR), blue wavelength fundus autofluorescence (FAF) and NIA.
Methods:
We conducted a retrospective review of all cases with the diagnosis of RPD, who presented to Doheny Retina Institute from 9/2007 to 11/2009. Patients were identified based on the imaging characteristics of RPD on IR as defined by Smith et al.1 Patients underwent OCT, IR, FAF, and NIA imaging (HRA2, Heidelberg Engineering Inc, Dossenheim, Germany). Registered IR and OCT images were studied to correlate the pattern and location of pathology in RPD.
Results:
There were a total of 46 patients identified with the diagnosis of RPD. The lesions showed some variability in the different imaging modalities. The lesions demonstrated hypoautofluorescence patterns on both FAF and NIA. The OCT in all patients revealed undulating alterations of the inner retinal pigment epithelial (RPE) layer. This pattern extended from the photoreceptor-RPE junction to the photoreceptor inner/outer segment (IS/OS) junction. The lesions as identified and correlated on FAF, NIA, and IR, did not show a one-to-one correlation with sub-RPE, or sub-retinal deposits.
Conclusions:
Although it is difficult to identify individual isolated drusen in RPD, point-to-point comparison of registered images in IR and OCT suggest that the RPD abnormalities lie at the inner aspect of the RPE. The hypoautofluorescent patterns seen on both FAF and NIA can differentiate lesions of RPD from the typical drusen seen with macular degeneration. The imaging pattern seen can shed light on the pathology of RPD lesions and their effect on lipofuscin and melano-lipofuscin granules of the RPE.1. Smith RT, Sohrab MA, Busuioc M, Barile G. Reticular macular disease. Am J Ophthalmol 2009;148(5):733-43 e2.
Keywords: drusen • imaging/image analysis: clinical • age-related macular degeneration