Multimodal imaging of autosomal dominant drusen

Background: Malattia Leventinese (ML) is a dominantly inherited macular dystrophy characterized by a radial pattern of drusen in the macular area and on the nasal edge of the optic disc. This case series describes the morphological features of drusen associated with ML using multimodal imaging.

History and signs: Three patients (two of the same family but only one with the ML phenotype) were analyzed by multimodal imaging including spectral domain optical coherence tomography (SD OCT) and genetic testing. In two patients multiple drusen in the macular region and around the optic nerve head were observed bilaterally. A radial pattern was only seen in one patient. These drusenoid deposits showed early hyperfluorescence in fluorescein angiography (FA) and intense staining in indocyanine green angiography similar to cuticular drusen (basal laminar drusen). The corresponding SD OCT scan revealed two types of deposits. The first, more prominent type, were focal nodular sub-retinal pigment epithelium (RPE) deposits. The second type of deposit appears to be localized on the anterior part of the RPE comparable to subretinal drusenoid deposits (SDD; reticular pseudodrusen).

Therapy and outcome: A single nucleotide variation c.1033C>T (p.R345 W) in the EFEMP1 gene was found in case 1 (classic ML), but could not be detected in case 2 and 3. So far our patients have not suffered from any visual complaints and have not developed choroidal neovascularization. They will be followed up regularly.

Discussion: Multimodal imaging including SD OCT provided new information about the appearance of drusen in eyes with ML/early onset drusen. In addition to the sub-RPE deposits some deposits appear above the RPE, however have different characteristic findings on FA/ICG, autofluorescence, near infrared reflectance and blue light imaging than SDD observed in patients with age-related macular degeneration. SD OCT alone might not be sufficient to characterize these type of drusen in ML.