The fundus photo shows subtle grayish discoloration nasal to the fovea in the left eye. The fluorescein angiogram was unremarkable. The OCT reveals swelling nasal to the fovea with subtle hyper-reflectivity at the level of the inner plexiform, inner nuclear, and outer plexiform layers. These findings are consistent with a rare condition called paracentral acute middle maculopathy (PAMM). Patients with PAMM, as with our patient, typically experience a sudden loss of central vision or a paracentral scotoma, and associated photopsias have been reported. Prior reports have hypothesized an ischemic etiology, implicating caffeine, vasoconstrictors, or systemic diseases associated with vascular occlusions. Our patient, with diabetes and hypertension, was at risk of microvascular occlusive disease. PAMM should be distinguished from acute macular neuroretinopathy, which likely has an inflammatory of infectious etiology and typically presents with central or paracentral disruptions of the ellipsoid zone on OCT. The scotoma in patients with PAMM is usually permanent. Our patient was observed closely and not treated, and she has not experienced a visual change four months after her initial presentation.
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