Donor Site Evaluation Using Multispectral Optoacoustic Tomography in Patients with Head and Neck Cancer Who Require Free Flap Transplant Surgery

Head and neck cancer surgery requires autologous tissue transplants to reconstruct resection defects. The outcome of reconstructive surgery is often limited by perfusion-associated complications. To improve patient outcome, innovative approaches to detect perfusion deficits are essential for selecting the optimal free flap transplant donor site. Methods: A clinical pilot study was conducted that included 16 patients with head and neck cancer who were undergoing surgery and 10 healthy controls. Multispectral optoacoustic tomography (MSOT) was performed before surgery at the most common donor sites (radial forearm, latissimus dorsi, anterolateral thigh, and distal fibula). The biomarker of oxygen saturation in muscle and in the dermal layer was compared between healthy controls and patients and was correlated with clinical postsurgical outcomes. Results: MSOT examinations caused no adverse reactions and integrated smoothly into the clinical workflow. MSOT-derived muscle oxygen saturation showed significant differences between patients and healthy controls at all donor sites. These disparities became more pronounced under muscle provocation, revealing perfusion deficits that were previously not detected. Furthermore, exercise revealed side-to-side differences in hemoglobin saturation that exceeded 20%. Patients experiencing postoperative complications exhibited substantially reduced preoperative perfusion levels. Conclusion: In this clinical study, we demonstrated the feasibility of MSOT for donor site evaluation in autologous transplant surgery. Our findings highlight the potential of MSOT-derived hemoglobin metrics as functional imaging biomarkers for detection of perfusion deficits.