Final dominant venous outflow patterns and intraoperative pedicle management in submental island flap reconstruction: a retrospective descriptive study of 20 patients

The venous anatomy of the submental island flap is variable, and the first venous confluence may not represent the final dominant venous outflow route considered important for maintaining venous drainage during flap transfer. This study retrospectively described the final dominant venous outflow patterns observed in this cohort, distinguished the first venous confluence from final dominant outflow, and summarized their technical relevance to intraoperative venous preservation and pedicle management. Twenty consecutive patients who underwent tumor resection followed by immediate submental island flap reconstruction between February 2017 and February 2019 were included. Final dominant venous outflow was identified and documented intraoperatively by the operating surgeon through direct dissection and tracing of the venous pathway. Given the small sample and sparse outcome events, analyses were descriptive. Thirteen flaps were antegrade, five were perforator-based, and two were reverse-flow. Final dominant outflow entered the external jugular system in 12 patients and the internal jugular system in eight. All three pedicle configurations occurred with both outflow patterns. Mean pedicle length was 6.7 ± 0.3 cm (range, 6.2–7.4 cm). All 20 flaps survived completely. Transient venous congestion occurred in three patients, with no partial necrosis, total flap loss, or reoperation for vascular compromise. In this cohort, final dominant venous outflow did not correspond to a specific pedicle configuration. Intraoperative identification of the final outflow route may help identify the vein considered important to preserve and prompt assessment of pedicle tension, kinking, twisting, and compression after transfer. These findings are descriptive technical observations and should not be interpreted as causal or definitive criteria for pedicle selection. The two reverse-flow cases are insufficient to support broad conclusions regarding safety or general applicability.