Purpose: To determine the specific location of the initial lesion in acute retinal pigment epitheliitis.
Methods: Four patients diagnosed with acute retinal pigment epitheliitis were studied. Fundus photographs, fluorescein angiography and indocyanine green angiography, and spectral-domain optical coherence tomography findings were reviewed.
Results: Four healthy young patients presented with acute onset of unilateral decreased vision. Ophthalmoscopy showed macular pigment mottling with surrounding yellow hypopigmented areas at the level of the retinal pigment epithelium (RPE). Fluorescein angiography revealed transmission hyperfluorescence. Early-phase and midphase indocyanine green angiography images showed a patchy macular hyperfluorescence. At late phase of indocyanine green angiography, a hyperfluorescent halo with a cockadelike appearance of the macular area was observed. Spectral-domain optical coherence tomography showed a disruption of the photoreceptors' inner segment and outer segment interface associated with a wider disruption of the RPE inner band. These disrupted lines were replaced by a dome-shaped highly reflective lesion involving the RPE inner layer, the photoreceptors' inner segment and outer segment layers, and, in two cases, the outer nuclear layer. With time, indocyanine green angiography showed resolution of the observed lesions. Spectral-domain optical coherence tomography showed restored and continuous inner segment and outer segment layers and RPE inner band.
Conclusion: Spectral-domain optical coherence tomography findings suggest that the initial lesion in acute retinal pigment epitheliitis is located at the junction between the photoreceptor outer segments and the apical side of the RPE cells. Indocyanine green angiography and spectral-domain optical coherence tomography show that the RPE appears to be more widely involved than the neurosensory retina.