Paracentral Acute Middle Maculopathy following Surgically Induced Branch Retinal Artery Occlusion During Vitrectomy

Paracentral acute middle maculopathy (PAMM) is a spectral-domain OCT finding of a thickened hyperreflective band at the level of the intermediate layers of the inner retina, attributed to the acute phase of intermediate capillary ischemia. The purpose of this paper is to report a case of PAMM deriving from a surgically induced branch retinal artery occlusion (BRAO) during vitrectomy for vitreous hemorrhage. A 70-year-old female referred to the posterior segment office with a 1-month history of visual loss in her right eye. Best-corrected visual acuity (BCVA) was "counting-fingers" (CF) due to a dense vitreous hemorrhage. She underwent a standard 23-gauge vitrectomy with a relatively close to the optic disc endodiathermy application to an avulsed vessel. Follow-up examination revealed a well-demarcated retinal whitening involving the inferior macula. SD OCT showed a surgically induced branch retinal artery occlusion exhibiting both a cotton wool spot and a PAMM lesion. Our case affords an insight into those pathological processes involved with PAMM, providing angiographic evidence of the retinal ischemic changes responsible for its development, by angiographically proving that branch retinal artery occlusion leads to a prompt formation of both a cotton wool spot and a PAMM lesion. Our aim is to raise awareness of this potential complication of vitrectomy surgery, especially when involving multiple traumatic manipulations onto the retinal surface.