Purpose: To describe macular lesions in patients with deferoxamine (DFO) retinopathy, and to follow their clinical course using multimodal imaging.
Methods: The authors retrospectively reviewed charts and multimodal imaging of 20 patients with β-thalassemia diagnosed with DFO retinopathy (40 eyes) after a minimum of 10 years of DFO treatment. Imaging included fundus photography, near-infrared reflectance and fundus autofluorescence imaging on confocal laser scanning ophthalmoscope, and spectral domain optical coherence tomography.
Results: Mean age of the 20 patients was 45 years, and mean duration of subcutaneous DFO therapy was 32 years (range, 20-52 years). Ten patients (50%) showed different types of pattern dystrophy-like fundus changes, including butterfly shaped-like (n = 3), fundus flavimaculatus-like (n = 3), fundus pulverulentus-like (n = 3), and vitelliform-like (n = 1) changes. Ten patients (50%) presented only minimal changes in the macula; these patients were significantly younger than patients presenting other patterns (P = 0.023). Confocal laser scanning ophthalmoscope and spectral domain optical coherence tomography showed that these abnormalities were more diverse and widespread than expected by ophthalmoscopy. Abnormal fundus autofluorescence and/or near-infrared reflectance signals corresponded to accumulation of material located within the outer retina or in the Bruch membrane-retinal pigment epithelium (RPE) complex on spectral domain optical coherence tomography. Follow-up examinations during a 40-month period revealed progressive development of RPE atrophy in areas of pattern dystrophy-like changes.
Conclusion: DFO retinopathy included a variety of pattern dystrophy-like changes or minimal changes affecting the RPE-Bruch membrane-photoreceptor complex. Multimodal imaging demonstrated that fundus changes were more diverse and widespread than expected from ophthalmoscopy. Consistently with previous histologic description of DFO retinopathy, multimodal imaging confirmed that photoreceptor outer-derived retinoids, various fluorophores, and RPE displacement or clumping are involved in DFO retinopathy, finally leading to frank RPE atrophy in most cases of pattern dystrophy-like changes.