RECONSTRUCTIVE Facial Transplantation: An Anatomic and Surgical Analysis of the Periorbital Functional Unit Dalibor Vasilic, M.D. Background: Complete loss of eyelid pair is associated with chronic discomfort, John H. Barker, M.D., Ph.D. corneal ulceration, and visual impairment. Contemporary reconstructive tech- Ross Blagg, M.S. niques rarely provide functionally acceptable results. Composite tissue allo- Iain Whitaker, M.D. transplantation may provide a viable alternative. This study reports on neuro- Moshe Kon, M.D., Ph.D. vascular anatomy and technical details of harvesting an isolated periorbital unit M. Douglas Gossman, M.D. and discusses its functional potential. Louisville, Ky.; and Utrecht, Methods: Twenty-four hemifaces (12 fresh cadavers) were dissected to study sur- The Netherlands gically relevant neurovascular structures and to develop an efficient harvest method. Angiographic analysis was performed in seven hemifaces following harvest. Results: The superficial temporal and facial vessels demonstrated consistent loca- tion and diameters. Anatomic variability was characterized by the absence of the frontal branch of the superficial temporal artery or facial-to-angular artery contin- uation, but never of both vessels in the same hemiface. Angiographic analysis demonstrated filling of the eyelid arcades, provided the anastomoses between the internal and external carotid branches were preserved. The facial nerve exhibited consistent planar arrangement and diameters in the intraparotid and proximal extraparotid regions, but less so in the distal nerve course. The inferior zygomatic and buccal branches frequently coinnervated the orbicularis oculi and lower facial muscles with an unpredictable intermuscular course. Based on the foregoing, an effective surgical harvest of the periorbital composite was developed. Conclusions: Surgical harvest of a functional periorbital allotransplant is techni- cally feasible. Revascularization of the isolated periorbital unit is influenced by variations in regional anatomy and cannot be guaranteed by a single vascular pedicle. The orbicularis oculi muscle and its innervation can be preserved, and recovery, albeit without the certainty of reflexive blinking, is expected. (Plast. Reconstr. Surg. 125: 125, 2010.) oss of an ipsilateral or bilateral eyelid pair is ment of original tissues1–3 or replacement with associated with chronic discomfort, corneal autologus grafts and flaps from remote sites.4,5 Lulceration, and visual loss. Current recon- Given the complex functional anatomy of the eye- structive methods include retrieval and reattach- lid unit, this injury presents a reconstructive chal- lenge that is typically associated with poor func- From the Department of Surgery and the Division of Plastic tional and aesthetic outcomes (Fig. 1). Revision and Reconstructive Surgery, University of Louisville, and surgery provides limited improvement and carries the Department of Plastic, Reconstructive, and Hand Sur- the burden of additional donor-site morbidity. gery, University of Utrecht. Composite tissue allotransplantation, intro- Received for publication March 16, 2009; accepted July 10, duced recently for facial reconstruction, could 2009. provide an alternative to current treatments. The Presented at the European Association of Plastic Surgeons Meet- cases performed so far have transplanted nasal ing, in Barcelona, Spain, May of 2009; in part at the British Association of Plastic, Reconstructive, and Aesthetic Surgery Summer Meeting, in Deauville, France, July of 2007; at Re- search!Louisville, in Louisville, Kentucky, October of 2007; and at the British Burn Association’s 40th Annual Scientific Disclosure: There are no financial conflicts of in- Meeting, in Swansea, United Kingdom, April of 2007. terests between any of the authors listed in this article Copyright ©2009 by the American Society of Plastic Surgeons and the work described in it. DOI: 10.1097/PRS.0b013e3181c2a5cc www.PRSJournal.com 125 Plastic and Reconstructive Surgery • January 2010 venous tributaries were studied from their proxi- mal origins to the orbicularis oculi. Facial nerve position, diameter, and branch patterns relevant to the orbicularis innervation were measured and mapped. Based on our anatomic observations and de- scriptions from the pertinent literature,6–28 differ- ent surgical planes of approach were evaluated. The resulting surgical sequences were designed to preserve essential functional constituents of the periorbital unit, while assuring perfusion and fa- cial nerve input during the entire harvest. Vascular integrity was evaluated angiographi- cally in seven harvested periorbital units. After the surgical protocol (see Periorbital Unit Harvest Fig. 1. Quadrilateral full-thickness eyelid loss was recon- Protocol in the Results section), each unit was structed with mucous membrane and skin grafts. Nearly total delicately dissected en-bloc, removed from the ca- tarsorrhaphy is required to prevent corneal desiccation. daver, and fixed to a radiolucent board for imag- ing. Each of the external carotid arterial branches and perioral tissues to treat midface and lower in five isolated periorbital units was identified, facial defects with encouraging preliminary cannulated, injected with radiopaque fluid [Ox- outcomes.6–8 Replacing damaged or missing peri- ilan 350 (Ioxilan), Guerbet Group, Bloomington, orbital tissues with a healthy periorbital unit allo- Ind.], and flushed with saline. Extravasation of graft is compelling; however, this methodology radiopaque fluid was minimized using cauteriza- has yet to be addressed. tion (bipolar coagulation) and ligation (monofil- In this article, we report our anatomic analysis ament nylon, 9.0 and 10.0). The periorbital allo- of myoneural and vascular constituents that are grafts were imaged in an angiographic suite essential to the function of a periorbital and eyelid (Innova 3100C, GE Healthcare, Waukesha, Wis.). pair allograft. Specifically, we studied location and The contribution of each arterial branch to per- constitution of vascular tributaries and facial nerve fusion of the eyelids and the orbital arcades branches relevant to this unique surgical under- was analyzed by observing radiopaque filling pat- taking. The resulting anatomic knowledge pro- terns. The venous system was assessed using the vided the foundation for preservational harvest of same angiographic technique in two isolated peri- a complete periorbital functional unit. To our orbital units. knowledge, this is the first study to analyze and describe the principal complexities of surgical re- RESULTS construction of the periorbital functional unit by allotransplantation of an eyelid pair. Vascular Anatomy Proximal superficial temporal and facial ves- sels demonstrated consistent anatomic location MATERIALS AND METHODS and diameter in all cadavers; however, their distal Twelve fresh cadavers (24 hemifaces, eight components demonstrated variability. The frontal male and four female; age range, 49 to 99 years) branch of the superficial temporal artery was ab- were dissected and studied using loupe magnifi- sent in two hemifaces, while that of the superficial cation (3.5ϫ) and an operative microscope temporal vein was missing in five of 18 dissected (OPMI 1F; Zeiss, Oberkochen, Germany; 10 to specimens. The course of the vessels was predom- 25ϫ). A Vernier caliper (1/20 mm; Kanon Instru- inantly linear, although tortuosity was common in ments, Tokyo, Japan) and a grid (2 mm in 200 the proximal segments of the frontal branch of the parts; E. Leitz GmbH, Wetzlar, Germany) were superficial temporal artery. The frontal branch of used to record all measurements. None of the the superficial temporal vein was equally likely to dissected specimens had a history of congenital occur superior or inferior to the artery. facial malformation, trauma, or surgery. The facial vein followed the lateral margin of Location, pattern, dimensions, and anatomic the artery in all cases. A distinct continuation of variations of the surgically relevant external ca- the facial to angular vessels, however, was missing in rotid and internal carotid arterial branches and five of 18 hemifaces. In one hemiface, a varicosity was 126 Volume 125, Number 1 • Facial Transplantation the only vascular structure identified in the medial canthus. Simultaneous absence of the frontal branch of the superficial temporal artery and facial- to-angular artery continuation was not observed. Based on observations in six hemifacial spec- imens, internal carotid branches were found to be unsuitable for primary allograft revascularization due to small caliber (0.6 Ϯ 0.2 mm and 0.8 Ϯ 0.2 mm, respectively) for the supraorbital and su- pratrochlear arteries. The supraorbital artery bi- furcated in four of six hemifaces below the surface of orbicularis oculi. The supratrochlear artery was absent in one hemiface, and tortuosity marked the extraorbital course of both vessels. Table 1 summarizes the course and diameter of the vessels, and Figure 2 depicts critical anatomic coordinates of the external carotid tributaries. Facial Nerve Fig. 2. The topographical coordinates of the external carotid tributaries that supply the periorbital unit depicted here are de- Dissection results are presented by facial nerve tailed in Table 1. AB denotes distance from the tragus to STA/STV; regions supplying the orbicularis oculi muscle. BC and BD denote distances to the STA and STV bifurcation, re- spectively; EF denotes distance from the frontal branch of the Temporal