ABSTRACT
We aim to present a case with bilateral sequential paracentral acute middle maculopathy (PAMM). A 57-year-old man presented with paracentral scotoma in the left eye. The patient’s multimodal imaging findings were consistent with PAMM in the left eye. Extensive systemic work-up revealed hypertension and a history of cerebrovascular event. One year after initial presentation, the patient had a subsequent decrease in visual acuity in the right eye and developed optical coherence tomography findings consistent with PAMM, whereas the left eye showed resolved PAMM findings. Although rare, PAMM can occur bilaterally. Clinicians should monitor unilateral PAMM patients with systemic vasculopathy for involvement in the fellow eye.
Introduction
Paracentral acute middle maculopathy (PAMM) is a recently defined retinal entity characterized by a hyperreflective parafoveal band at the level of the inner nuclear layer (INL) on spectral-domain optical coherence tomography (SD-OCT) corresponding to ischemia in the deep retinal capillary plexus.1
PAMM can be isolated or associated with several retinovascular and systemic diseases such as retinal artery or vein occlusion (RVO), diabetic retinopathy, Purtscher retinopathy, and sickle-cell retinopathy.2,3,4 Despite the substantial number of unilateral PAMM cases in the literature, there is little information on the bilateral involvement of PAMM. Herein, we aim to report a patient who presented with acute PAMM in one eye and subsequently developed PAMM in the fellow eye during follow-up.
Discussion
Herein, we document a patient with a history of hypertension and cerebrovascular event who presented with PAMM in one eye and later developed PAMM in the fellow eye. Initially, the first eye showed characteristic acute PAMM findings, then had signs of chronic (resolved) PAMM in the form of INL thinning associated with outer plexiform layer disruption/elevation. The subsequent development of INL thinning corresponding to the original PAMM lesion suggests that ischemia of the intermediate and deep capillary plexuses may be the primary etiology.
Though PAMM has been associated with various ocular and systemic conditions, a recent study reported that the condition may occur even in asymptomatic patients with unknown systemic disease.5 In a recent study, chronic PAMM lesions were detected in 89.9% of hypertensive patients and 16.7% of healthy individuals.5 Moreover, the likelihood of developing chronic PAMM lesions was significantly higher in patients with mild hypertension, which may suggest that these lesions are the earliest changes in retinal microcirculation before changes in OCTA parameters become apparent. In another study, the prevalence of resolved PAMM lesions in the fellow eyes of patients with unilateral RVO was found to be as high as 71.2%, whereas 19.3% of age-matched healthy individuals displayed similar findings.6
In conclusion, patients with systemic vascular pathologies are at risk for developing bilateral PAMM, which may occur sequentially. These patients should be monitored closely for involvement of the fellow eye.
