A Unique Presentation of Focal Auricular Arteriovenous Malformation: from Embryology to Angiosome Theory.

Background: Auricular arteriovenous malformations (AVMs) are rare vascular anomalies, being the second most prevalent after cheek AVMs. Their management presents challenges. Objective: We aim to explore the clinical presentation of ear AVMs, highlighting a unique pattern of focal auricular AVM. Methods: A retrospective review was conducted over 7 years, focusing on patients diagnosed with focal auricular AVMs. Exclusions included non-AVM diagnosis, adjacent anatomical site extensions, and lack of patient information or photos. Results: Twenty-two patients with auricular AVMs were identified, 13/22 with isolated focal AVMs, 8/13 females, 5/13 males, 5/13 with right ear involvement, and 8/13 with left ear involvement. A consistent presentation involving the upper 2/3 of the pinna while sparing the root of the helix/tragus/antitragus/concha and lobule was noticed. Conclusion: This study focuses on focal auricular AVMs, revealing a uniform pattern while sparing specific structures. Embryological evaluation, vascular supply analysis, and angiosome theory shed light on potential tissue layers as the nidus in those cases.