Paracentral Acute Middle Maculopathy
Paracentral acute middle maculopathy (PAMM) refers to acute ischemic events that affect the deep macular capillary layers. It is best visualized as hyperreflective bands on SD-OCT. There are 2 variants: type 1 affects the superficial capillary plexus in the outer plexiform layer (OPL)/inner nuclear layer (INL) region, and type 2 affects the deep capillary plexus in the OPL/outer nuclear layer (ONL) region. Visual consequences vary; upon resolution, type 1 lesions produce INL thinning, and type 2 lesions cause disturbance of the ellipsoid or inner segment and outer segment line.
Sarraf D, Rahimy E, Fawzi AA, et al. Paracentral acute middle maculopathy: a new variant of acute macular neuroretinopathy associated with retinal capillary ischemia. JAMA Ophthalmol. 2013;131(10):1275–1287.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.