Hypoplastic Facial Artery and Allotransplantation of the Lower Two-Thirds of the Face

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Sir:FigurePartial facial allotransplantation allows reconstruction, in a single surgical procedure, of complex midfacial injuries with massive tissue loss. Currently, a bipedicled flap based on the facial arteries and facial veins is proposed for allotransplantation of the lower two-thirds of the face. We report the case of a cadaveric specimen with bilateral hypoplastic facial arteries, compensated with a more developed transverse facial artery on both sides (Fig. 1).Fig. 1: Angiogram obtained from a cadaveric specimen of both transverse facial arteries performed after the harvest of the flap. TFA, transverse facial artery; FA, facial artery; LNA, lateral nasal artery; ILA, inferior labial artery; SLA, superior labial artery.We realized a dynamic subtraction angiography and dye injections on a flap of the lower two-thirds of the face. Only the chin and the lower lip were stained during the injections of both facial arteries, whereas the injections of both transverse facial arteries stained the majority of the lower two-thirds of the face. To evaluate the frequency of this anatomical variation, we studied 400 facial arteries from 200 patients who had undergone computed tomographic angiography (Fig. 2).Fig. 2: Computed tomographic angiogram of a 23-year-old man with a unilateral variation. TFA, transverse facial artery; FA, facial artery; FV, facial vein.Of the 200 patients, 120 were male and 80 were female, with a mean age of 55.7 years (range, 17 to 90 years). None of them had undergone any surgery involving the head and neck area. We found this bilateral abnormality in one patient (0.5 percent). In five other patients, it was a unilateral abnormality (2.5 percent). Hypoplastic facial artery is a known variation1 with a frequency varying between 0 and 9 percent in the data reported in the literature. When the facial artery is hypoplastic, the face is supplied either by a more developed contralateral facial artery or by the transverse facial artery and infraorbital artery of the ipsilateral side.2 Computed tomographic angiography can be used in the preoperative assessment of facial donor vessels in transplantation. It is a rapid and noninvasive study, with wider availability. Computed tomographic scanning has the ability to analyze the facial skeleton, which is necessary to optimize donor/recipient matching in case of composite facial transplantation, including bones. The ability to display the vascular structures in three dimensions makes interpretation easy for surgeons. Moreover, many countries require confirmation of the clinical diagnosis of brain death by a paraclinical examination. During this examination, facial vessels can be assessed, as can the whole body, allowing the detection of any anatomical variant of organs for potential organ harvesting. Devauchelle et al.,3 Meningaud et al.,4 and Pomahac et al.5 reported complete revascularization from a single facial pedicle when they performed a partial facial graft of the lower two-thirds of the face. However, in all of these cases, anastomoses were carried out on both sides. We think that, in case of a unilateral variation, the revascularization of the entire flap could be accomplished with the contralateral facial artery. If a second arterial anastomosis must be performed, our study demonstrates that the anastomosis of the transverse facial artery would be safer than the anastomosis of the hypoplastic facial artery. If the donor presents a bilateral variation, the transverse facial artery can be used as an alternative arterial pedicle to assume the blood supply of the lower two-thirds of the face. This variation is rare, but success of the face transplant is so important that a simple preoperative examination seems necessary to detect this anatomical variation and allow the surgeon to use the transverse facial artery as an alternative arterial pedicle. Mathieu Bondaz Department of Oral and Maxillofacial Surgery, Centre Hospitalier Universitaire, and, Department of Anatomy, Université Bordeaux 2 Anne-Sophie Ricard, M.D. Department of Oral and Maxillofacial Surgery Jerome Berge, M.D. Department of Diagnostic and Interventional Neuroradiology, Centre Hospitalier Universitaire Philippe Caix, M.D., Ph.D. Mathieu Laurentjoye, M.D. Department of Oral and Maxillofacial Surgery, Centre Hospitalier Universitaire, and, Department of Anatomy, Université Bordeaux 2, Bordeaux, France DISCLOSURE The authors have no commercial associations or financial disclosures that might pose or create a conflict of interest with information presented in this article.

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