Paracentral acute middle maculopathy following internal carotid artery stenting

Area of Science:

• Ophthalmology
• Vascular Neurology
• Interventional Cardiology

Background:

• Internal carotid artery stenting (ICAS) is a common procedure for high-grade stenosis.
• Embolic protection devices (EPDs) are used during ICAS to minimize distal embolization.
• Paracentral acute middle maculopathy (PAMM) is a retinal condition affecting the macula.

Observation:

• A 74-year-old male developed PAMM one week post-ICAS despite using a filter-type EPD.
• Ocular examination revealed a parafoveal gray lesion, confirmed by OCT as a hyperreflective band in the inner nuclear layer.
• The patient was asymptomatic, and the PAMM lesion resolved within 10 weeks.

Findings:

• PAMM occurred despite the use of a filter-type EPD during ICAS.
• Potential causes include embolic debris passing through the filter or debris released during filter deployment/retraction.
• The observed PAMM lesion was asymptomatic and fully resolved.

Implications:

• This case suggests that current filter-type EPDs may not completely prevent embolic events leading to PAMM.
• Further research into EPD efficacy and PAMM pathogenesis after ICAS is warranted.
• Ophthalmologists should consider ICAS as a potential trigger for PAMM in relevant patient populations.