Background: Postoperative free flap monitoring is a critical part of reconstructive microsurgery. Postoperative clinical assessments rely heavily on specialty-trained staff. Therefore, in regions with limited specialist availability, the feasibility of performing microsurgery is restricted. This study aimed to apply artificial intelligence in postoperative free flap monitoring and validate the ability of machine learning in predicting and differentiating types of postoperative free flap circulation. Methods: Postoperative data from 176 patients who received free flap surgery were prospectively collected, including free flap photographs and clinical evaluation measures. Flap circulation outcome variables included normal, arterial insufficiency, and venous insufficiency. The Synthetic Minority Oversampling Technique plus Tomek Links (SMOTE-Tomek) was applied for data balance. Data were divided into 80%:20% for model training and validation. Shapley Additive Explanations were used for prediction interpretations of the model. Results: Of 805 total included flaps, 555 (69%) were normal, 97 (12%) had arterial insufficiency, and 153 (19%) had venous insufficiency. The most effective prediction model was developed based on random forest, with an accuracy of 98.4%. Temperature and color differences between the flap and the surrounding skin were the most significant contributing factors to predict a vascular compromised flap. Conclusions: This study demonstrated the reliability of a machine-learning model in differentiating various types of postoperative flap circulation. This novel technique may reduce the burden of free flap monitoring and encourage the broader use of reconstructive microsurgery in regions with a limited number of staff specialists.

Necrotizing fasciitis (NF) is uncommon but potentially lethal when it is associated with systemic disorders. We report a case of odontogenic NF in a patient with uncontrolled diabetes mellitus. The patient was referred on day 10 since the onset of odontogenic NF. Protective tracheostomy, local facial-cervical fasciotomy were conducted and broadspectrum antibiotics were given, subsequent serial surgical drainage and debridement were performed in theater. Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumonia were isolated. Five staged debridements were performed to the targeted anatomic regions thus reducing surgical time and blood loss. The patient survived the acute infection and received subsequent reconstruction. Cervical NF with descending mediastinitis and periorbital NF is associated with high mortality rates. This is the only known report of an adult who survived NF affecting entire scalp, periorbital, cervical, and thoracic region. Early diagnosis and staged surgical planning minimize morbidity and mortality from NF.

Background: The medial sural artery perforator flap is a versatile option in reconstructive microsurgery. However, most reports of this flap have been limited by sample size. This study reviews the experience of a single large-volume center using the medial sural artery perforator flap and its variants for a variety of reconstructive purposes. Methods: A retrospective review of all patients who received the medial sural artery perforator flap reconstruction between March of 2006 and July of 2014 was performed. Results: Two-hundred medial sural artery perforator flaps were used at three anatomical regions: head and neck (n = 129), upper extremity (n = 47), and lower extremity (n = 24). Flaps were transferred as free (n = 189) and pedicled (n = 11). Overall flap survival was 96 percent. Flap variants used included chimeric flap (n = 11) and dual skin paddle (n = 2). Plantaris tendon and saphenous/sural nerve graft were harvested in conjunction in 20 and seven patients, respectively. In 5 percent of the cases harvested in the conventional manner, a reliable perforator could not be found. Conclusions: The medial sural artery perforator flap is a reliable, alternative workhorse flap for nearly any small- to medium-size defect. It can be harvested as free or pedicled and the option to include multiple tissue components further expands its versatility. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Background: The challenge of modern hand reconstruction goes beyond simple coverage. Thanks to the advances of microsurgery, there are ever-improving standards of functional and esthetic outcomes in hand reconstruction. The versatile donor site of the medial sural artery perforator flap can fulfill this purpose. Materials: Between June 2006 and October 2008, we used free medial sural artery perforator flaps for hand reconstruction in 14 cases. The sites of reconstruction included digits (n = 7), dorsal hand (n = 3), palmar hand (n = 2), and wrist (n = 2). Associated tendon and nerve defects were found in five patients. The plantaris tendon (n = 4), split Achilles tendon (n = 1), saphenous nerve (n = 1), and sural nerve (n = 1) were harvested for reconstructive purpose from the same donor site in this series. Results: The proximal perforator of the medial sural artery emerged 8 cm to 13 cm from the midpoint of the popliteal crease, correlating with the axis of the medial sural artery. Twelve flaps were raised with a single perforator. One flap failed because of perioperative vasospasm. The donor defect could be closed without skin grafts when the flap width was <6 cm. Conclusion: The free medial sural artery perforator flap transfer is appropriate for small- to medium-sized hand defect reconstruction. The donor site not only supplies a thin fasciocutaneous flap but also provides the option to harvest a segment of tendon or nerve graft through the same incision for composite tissue reconstruction in a single stage.