Paracentral Acute Middle Maculopathy and the Ischemic Cascade: Toward Interventional Management

Purpose: To present select cases of paracentral acute middle maculopathy (PAMM) demonstrating progressive vascular occlusion and the ischemic cascade and illustrate scenarios in which therapeutic intervention may be considered.

Design: Perspective.

Methods: Review and interpretation of selected literature, with perspective on the evaluation and management of patients with PAMM lesions. Multimodal imaging of 3 illustrative cases of PAMM are presented, including cross-sectional and en face optical coherence tomography (OCT), with progressive vascular occlusion and evidence of the ischemic cascade noted in 2 of the cases.

Results: All 3 cases showed evidence of PAMM at baseline, including perivenular PAMM in 2 cases. Progression from a mild central retinal vein occlusion (CRVO) to a more severe CRVO was noted in the first case, while the second case progressed from an incomplete to complete central retinal artery occlusion (CRAO). In the third case, there was resolution of PAMM lesions associated with partial CRAO after the patient began taking aspirin.

Conclusions: Perivenular PAMM can be the only presenting sign of retinal vascular occlusion. In such cases, it is important to differentiate between partial CRVO and incomplete CRAO as the underlying cause. We provide guidance on making this important distinction, which plays a critical role in directing the nature and urgency of the systemic work-up. In patients with PAMM caused by partial retinal arterial occlusion, a benign empirical approach, such as low-dose aspirin (81 mg), may be reasonable to reduce the likelihood of subsequent vision loss from progression to complete arterial occlusion. A clinical trial, however, is necessary to support such a strategy.