Vein-protection-first strategy revolutionizes submental artery perforator flap harvest success: the A-B-C technique and training assessment

Submental artery perforator flaps (SMAPF) represent valuable reconstructive options for head and neck defects, yet traditional artery-first dissection approaches inadequately protect complex submental vein (SMV) drainage variations, contributing to compromised flap outcomes. We systematically analyzed SMV drainage patterns to establish a standardized vein-protection-first technique. We retrospectively analyzed venous drainage patterns in 408 successfully harvested SMAPF cases (December 2017-December 2022), identifying source and peripheral drainage systems. A clinical dissection-based A-B-C technique was developed: Point A (intersection of the facial nerve marginal mandibular branch and facial vein), Point B (confluence of SMV and facial vein), and Point C (confluence of facial vein with internal jugular vein/external jugular vein/anterior jugular vein). Following standardized training of twelve surgeons, we conducted a retrospective pre-post comparative study comparing the conventional surgery group (January 1, 2023, to January 1, 2024; n = 62) and the vein-optimized group (February 1, 2024, to February 1, 2025; n = 55). The primary endpoint was flap compromise. All 408 SMAPF cases carried source drainage systems; 29.2% carried peripheral drainage. A-B-C classification revealed A-B-single C (93.4%), A-B-double C (5.6%), and A-B-triple C (1.0%) configurations. Spatial analysis identified Type I inverted T-shaped (18.1%) and Type II Y-shaped (81.9%) patterns. The vein-optimized group demonstrated significantly reduced flap compromise rates (OR = 0.183, 95% CI:0.040–0.844, p = 0.029), representing 81.7% risk reduction. Harvest time decreased significantly (p = 0.008). Multivariable analysis confirmed A-B-C technique as an independent protective factor. This novel A-B-C vein-optimized technique significantly reduces flap compromise and decreases operative duration. The standardized approach mitigates experience-dependent variability, providing a theoretical and practical framework for SMAPF clinical implementation and surgical training protocols.