New aspects in free flap surgery: Mini-perforator flaps and extracorporeal flap perfusion

Background: The scope of microvascular tissue transfer in the Head and Neck reaches from coverage of simple soft tissue defects to complex 3-D reconstructions using multiple or chimeric flaps. This paper summarises the presentation given at the Congress of the French Society of Oral and Maxillofacial Surgery in Marseille 2017. It was the aim of our work to add further elements to this wide spectrum of reconstructive possibilities.

Methods: For patients with small intraoral soft tissue defects in whom the use of a radial forearm flap would not be justified because of its donor site morbidity, but who nevertheless would take a benefit from a small free flap, we used mini-perforator flaps from the lower leg. These flaps were raised with negligible morbidity. Moreover, for patients necessarily needing a free flap, but having vessel depleted, irradiated necks, we have developed a first idea of extracorporeal flap perfusion to make microvascular anastomoses unnecessary.

Results: Using donor sites from the lower leg, mini-soleus and medial sural perforator flaps were raised to cover defects of 2×3 to 2×4cm at the anterior floor of the mouth or lateral tongue. The success rate was 91%, and despite their small size, the flaps helped to maintain the mobility of the tongue. The donor site morbidity was minimal. After extensive experimental work on small animals and human tissue, four flaps could successfully be transferred so far by means of extracorporeal perfusion. In these patients, autonomisation took place between 5 and 12 days.

Conclusions: Although microvascular tissue transfer already allows for reconstruction in almost any possible defect constellation, mini-perforator flaps and machine-perfused transplants seem to represent new aspects of free flap surgery, being useful extensions of the reconstructive surgeon's armament.