title: Infrared fluorescence imaging of lymphatic regeneration in nonhuman primate facial vascularized composite allografts.
abstract: BACKGROUND
  Clinical vascularized composite allografts (VCA), although performed with good success, have been characterized by rejection episodes and postoperative graft edema. We investigated lymphatic donor-recipient reconstitution and lymphatic regeneration in a nonhuman primate facial VCA model.
  
  
  METHODS
  Heterotopic partial face (n = 9) VCAs were performed in cynomolgus macaques. Grafts were monitored for rejection episodes and response to immunosuppressive therapies as previously described. Donor and recipient lymphatic channels were evaluated using a near-infrared handheld dual-channel light-emitting diode camera system capable of detecting fluorescence from indocyanine green injections. Graft lymphatic channels were serially evaluated from postoperative day 0 to 364.
  
  
  RESULTS
  Preoperative imaging demonstrated superficial lymphatic anatomy similar to human anatomy. Initial resolution of facial allograft swelling coincided with superficial donor-recipient lymphatic channel reconstitution. Reconstitution occurred despite early acute rejection episodes in 2 animals. However, lymphatic channels demonstrated persistent functional and anatomic pathology, and graft edema never fully resolved. No differences in lymphatic channels were noted between grafts that developed transplant vasculopathy (n = 3) and those that did not (n = 6). Dynamic changes in patterns of lymphatic drainage were noted in 4 animals following withdrawal of immunosuppression.
  
  
  CONCLUSIONS
  Donor-recipient lymphatic channel regeneration following VCA did not result in resolution of edema. Technical causes of graft edema may be overcome with alternative surgical techniques, allowing for direct investigation of the immunologic relationship between VCA graft edema and rejection responses. Mechanisms and timing of dynamic donor-recipient lymphatic channel relationships can be evaluated using fluorescent imaging systems to better define the immunologic role of lymphatic channels in VCA engraftment and rejection responses, which may have direct clinical implications.
authors.affiliation: Division of Plastic, Reconstructive & Maxillofacial Surgery, R Adams Cowley Shock Trauma Center, 22 South Greene Street, Baltimore, MD 21201, USA.
authors.forename: Gerhard S
authors.initials: GS
authors.lastname: Mundinger
authors.forename: Mitsunaga
authors.initials: M
authors.lastname: Narushima
authors.forename: Helen G
authors.initials: HG
authors.lastname: Hui-Chou
authors.forename: Luke S
authors.initials: LS
authors.lastname: Jones
authors.forename: Jinny S
authors.initials: JS
authors.lastname: Ha
authors.forename: Steven T
authors.initials: ST
authors.lastname: Shipley
authors.forename: Cinthia B
authors.initials: CB
authors.lastname: Drachenberg
authors.forename: Amir H
authors.initials: AH
authors.lastname: Dorafshar
authors.forename: Isao
authors.initials: I
authors.lastname: Koshima
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Bartlett
authors.forename: Rolf N
authors.initials: RN
authors.lastname: Barth
authors.forename: Eduardo D
authors.initials: ED
authors.lastname: Rodriguez
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging; D005145:Face / Q000098:blood supply* / Q000601:surgery*; D005453:Fluorescence; D006084:Graft Rejection / Q000175:diagnosis*; D006085:Graft Survival; D042601:Lymphatic Vessels / Q000502:physiology* / Q000637:transplantation*; D008252:Macaca fascicularis; D010781:Photography / Q000379:methods*; D012038:Regeneration; D014184:Transplantation, Homologous