Presumed idiopathic outer lamellar defects of the fovea and chronic solar retinopathy: an OCT and fundus autofluorescence study

Aim: To examine fundus autofluorescence (FAF) findings in eyes with presumed idiopathic outer lamellar defects (OLD) at the fovea and to discuss their pathogenesis. Methods: Prospective observational case series of five eyes of four patients presenting with OLD at the fovea defined as discrete lesions of 50-100 mm in size located at the level of the outer retina on biomicroscopy and imaged on optical coherence tomography (OCT) as cylindrical, well-demarcated interruption of hyper-reflective bands corresponding to the inner/outer segments junction of photoreceptors and to the complex retinal pigment epithelium-choriocapillaris; none of the enrolled patients had any positive history for direct sungazing, welding-arc or sunbed exposure, whiplash injury, ocular trauma, macular oedema/detachment or evidence of vitreomacular traction. The corresponding FAF images were evaluated. Results: In eyes with OLD, the neuroretina in the foveal region appeared to be thinner than in fellow, unaffected eyes. FAF revealed well-demarcated, hypoautofluorescent areas (corresponding in location to the OLD observed clinically and on OCT), surrounded by an irregular halo of relatively increased autofluorescence in the context of the greater hypoautofluorescent macular region. Conclusion: Biomicroscopy, OCT and FAF findings of presumed idiopathic OLD of the fovea strongly resemble those observed in association with chronic solar retinopathy. In association with OCT, FAF might represent a useful technique with which to detect subtle solar-induced injuries of the retina.