Expanding the Use of the Comaneci Neck-Bridging Device for Endovascular Treatment of Complex Renal Artery Aneurysms

Abstract

Background: Renal artery aneurysms (RAA) carry significant rupture risks, yet wide-neck variants challenge conventional endovascular techniques. Purpose: We report the successful exclusion of a wide-neck RAA using the Comaneci neck-bridging devide in a patient with renal fibromuscular dysplasia (FMD), highlighting its utility and limitations. Research design: Single-case report. Study sample: A 50-year-old hypertensive female with renal FMD presenting with a 27-mm saccular, wide-neck RAA. Data collection: Following multidiscplinary discussion favoring renal parenchyma preservation, endovascular coiling using the Comaneci device was performed via brachial access. The device stabilized the aneurysm neck during sequential coil (Hydroframe, Cosmos, Complex) placement. Posprocedural and 24-month follow-up imaging assesed occlusion, renal perfusion, and complication. Results: Postprocedural imaging confirmed complete aneurysm occlusion, preserved renal perfusion, and the abscense of complications, which was sustained at the 24-month follow-up. Conclusion: This case demonstrated the Comaneci device's safety and efficacy for excluding anatomically complex RAAs, particularly in FMD-associated vessels where permanent stents risk endothelial injury. Technical challenges include device sizing limitations in larger visceral arteries and the need for dual microcatheter strategies, underscoring operator expertise importance. Critical gaps identified are the lack of standarized protocols for visceral applications and insufficient long-term coil stability data. Findings advocate for device modifications for non-cerebral anatomies and prospective trials compating outcomes with balloon-assisted coiling or flow diversion. While highlighting the Comaneci's niche role in RAA management, cautious adoption is urged pending robust evidence.