The pattern dystrophies of the retinal pigment epithelium (RPE) include a group of disorders: Butterfly-type pattern dystrophy (Figs. 17.1, 17.2, 17.3, 17.4 and 17.5) Adult-onset foveomacular vitelliform dystrophy Sjögren's reticular-type pattern dystrophy Fundus pulverulentus.

Pseudoxanthoma elasticum (PXE) is a rare autosomal recessive disorder caused by mutations in the ABCC6 gene, resulting in various retinal lesions, among other systemic manifestations. Visual loss may occur in PXE, most commonly caused by choroidal neovascularization and macular atrophy, but little is known about the consequences of fundus pulverulentus (FP) in PXE. The aim of this study was to evaluate ophthalmic outcomes in patients with FP associated with PXE in a large series of PXE patients. In a retrospective observational study, ophthalmic outcomes were compared between two groups of age-matched patients with genetically and pathologically confirmed PXE: one group with FP versus one without FP. All included patients underwent thorough clinical examination. Further investigation (optical coherence tomography (OCT), Cirrhus, Zeiss Germany, and/or fluorescein/indocyanin green angiography) was performed in cases of suspected choroidal neovascularization (CNV). The study included 13 PXE patients with FP (group 1: 8 men and 5 women, aged 45-65 years) and 47 age-matched PXE patients without FP (group 2: 19 men and 28 women). Mean patient follow-up was 63 months (range 0-132 months). Subretinal fibrosis (SRF) was more frequently associated with FP (9/26 eyes, 34.6%), compared to absence of FP (4/94, 4.2%) (p = 0.0001). Independently of SRF, FP can evolve into deep macular atrophy and/or CNV with dramatic consequences for central vision. Fundus pulverulentus may occur in PXE and is most commonly associated with subretinal fibrosis in the posterior pole and visual loss by macular atrophy even in the absence of CNV.