Deferoxamine retinopathy includes pattern dystrophy-like changes

This study used multimodal imaging to demonstrate that fundus changes in deferoxamine retinopathy were more diverse and widespread than expected from ophthalmoscopy.

The authors reviewed the charts and multimodal images of 20 patients with β-thalessemia and confirmed deferoxamine retinopathy after a minimum of 10 years of deferoxamine treatment.

The mean duration of subcutaneous deferoxamine therapy was 32.7 ± 8.7 years with a standard dose ranging from 1.5 g/day to 4.5 g/day. The mean follow-up was 19.7 months.

Ten patients had pattern dystrophy-like retinal pigment epithelium (RPE) changes in the macula corresponding to irregular patterns on fundus autofluorescence imaging (FAF) and/or near-infrared reflectance (NIR) on confocal laser scanning ophthalmoscope: three with butterfly-shaped changes, three with fundus flavimaculatus, three with fundus pulverlentus and one with vitelliform.

Abnormal FAF and NIR imaging corresponded to accumulation of material within the outer retina or the Bruch’s membrane-RPE complex on SD-OCT. The authors described progressive development of RPE atrophy in the areas of pattern dystrophy-like changes on follow up.

The remaining 10 patients with only minimal clinical macular changes were described to have hyper-autofluorescent dots on FAF and hyperreflective dots on NIR. These areas correlated with focal thickenings of the RPE on SD-OCT. These changes did not show progression into pattern-dystrophy like changes. These patients were on average eight years younger than the other group.

The authors conclude that deferoxamine retinopathy in β-thalessemia patients included phenotypes of varying degrees of pattern dystrophy-like changes affecting the Bruch’s membrane-RPE-photoreceptor complex. The pattern dystrophy-like changes lead to RPE atrophy over time.