Free tissue reconstruction in the "vessel-depleted" neck: A multi-institutional cohort study.

Objectives: Much of the literature on free tissue reconstruction in the "vessel-depleted" neck is focused on identification of vessels outside the pretreated field and data on free flap outcomes when infield microvascular anastomosis is performed remain scarce. We aim to report on free flap outcomes and recipient vessel choice in a large cohort of patients with prior radiation and neck dissection (RTND) to the ipsilateral side of vessel anastomosis.

Methods: A retrospective review was performed including patients who received head and neck free tissue transfer following prior RTND to the ipsilateral side of vessel anastomosis. Pretreatment data, free flap type, defect site, and recipient vessel choice were reported. Recipient vessel choice was stratified according to neck dissection level and prior free flap. Primary outcome was free flap survival (total failure, partial failure, success) within 30 days after surgery.

Results: This study included 72 free flap cases in 68 patients. Free flap success was 94.4%; one case (1.4%) resulted in total flap loss and three cases (4%) had partial flap loss. The facial (35%), external carotid (ECA) (25%), and superior thyroid arteries (16%) were the most common recipient arteries. The external jugular (EJV) (38%), facial (30%), and internal jugular veins (IJV) (15%) were the most common recipient veins. The superior thyroid artery was used less frequently with a prior level 2-3/4 neck dissection compared to a prior level 1-3/4 neck dissection (6% vs. 17%, p = 0.83). The facial artery (7% vs. 67%, p < 0.01) and vein (13% vs. 46%, p = 0.04) were used less frequently when a prior free flap with ipsilateral anastomosis was performed. The superior thyroid, ECA, IJV, and EJV were more commonly used in this subgroup.

Conclusion: Free tissue transfer with infield microvascular anastomosis in a neck with prior RTND can be safely done with comparable outcomes to surgically naïve, non-irradiated necks.