No abstract

Background Success of free tissue transfer depends on standardized intraoperative flap design, microsurgical technique, and postoperative monitoring. We sought to investigate whether laser speckle imaging (LSI) is suitable for optimization of intraoperative flap design and postoperative monitoring of free flaps with skin paddles. Methods Skin perfusion was assessed with LSI in 27 free flaps after dissection at the donor site, after anastomosis at the recipient site, after inset and on postoperative days (POD) 1, 5, and 10. Skin perfusion of the whole flap (ROI [region of interest]-1) and the area over the pedicle (ROI-2) were compared between patients with and without postoperative complications (POC+ and POC − , respectively). A receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff for perfusion during LSI-guided microsurgery. Results In flaps without or only minor POC, intraoperatively measured perfusion over ROI-2 was significantly higher compared with ROI-1, whereas no significant differences were found for flaps with major POC. Perfusion of ROI-1 and 2 intraoperatively and on POD 1 was significantly lower in the POC+ compared with the POC− group (p < 0.05). ROC analysis yielded a threshold of 107 perfusion units (PU) at ROI-2 with an area under the curve (AUC) of > 0.8 for identification of flaps with major POC. Conclusion LSI is an easy to use, noninvasive technique for identification of malperfused areas in free flaps, thus allowing for intraoperative decision-making on flap dimensions and postoperative monitoring. LSI therefore is a valuable tool for perfusion assessment with a high potential to become an established part of microsurgical practice.

Background Free adipocutaneous anterolateral thigh (ALT) flaps have evolved as workhorse flaps to reconstruct complex, multicompound defects. While coverage is safely achieved, flaps may remain bulky. As a standard of care, flaps are refined with liposuction, partial excision, or combination of both. Cryolipolysis is widely used for fat reduction in esthetic medicine. This pilot comparative study analyses whether cryolipolysis may serve as a safe alternative method to effectively reduce volume in fasciocutaneous flaps. Moreover, patients' satisfaction with the procedure is evaluated. Methods In this single-center, retrospective, interventional comparative cohort study, 10 patients with free subfascial ALT flaps for distal extremity reconstruction underwent cryolipolysis (60 minutes, −9°C). Circumference of the extremities and subcutaneous fat thickness were determined before (T1) and 12 weeks (T2) after cryolipolysis. Patient satisfaction was evaluated with a questionnaire of Likert's scale questions. Duration of hospital stay, intervention time, costs, and possible complications were analyzed and compared with surgical flap contouring (n = 12). Results All patients undergoing cryolipolysis were male, with a median age of 52 years without arterial disease-like state or deep vein thrombosis (DVT). At T2, a significant reduction of circumference of 1.8 ± 0.9 cm (p < 0.001) and subcutaneous fat layer of 7.7 ± 3.0 mm (p < 0.0001) was recorded. Overall, 90% of the patients were satisfied with the result. Cryolipolysis was well tolerated. One patient developed a second-degree frostbite which healed without further intervention. Cryolipolysis proofed to be as safe as surgical flap contouring. Hospital stay was significantly shorter (p < 0.01) and personal resources were spared when flap contouring was performed with cryolipolysis. Conclusion This is a novel application of evolving body-contouring cryolipolysis from esthetic medicine into optimizing outcomes in reconstructive surgery. Cryolipolysis has been shown to be relatively safe and effective to reduce ALT's volume with high patients' satisfaction. This successful pilot study encourages further investigation with a prospective randomized control trial.