title: Three-dimensional computed tomography reveals different donor-site deformities in adult and growing microtia patients despite total subperichondrial costal cartilage harvest and donor-site reconstruction.
abstract: BACKGROUND
  Donor-site deformity may complicate autologous costal cartilage harvest for microtia reconstruction. This is reportedly prevented by total subperichondrial costal cartilage harvest, costochondral growth center preservation, donor-site reconstitution with morselized leftover costal cartilage, and perichondrial repair (Kawanabe-Nagata method). However, no quantitative assessment of preoperative versus postoperative thoracic morphology exists following use of this method.
  
  
  METHODS
  Twenty-five consecutive patients (11 adult and 14 growing patients) who received radiographic donor-site evaluation for autologous unilateral primary microtia reconstruction were studied. Each underwent thoracic three-dimensional computed tomography preoperatively and 6 months postoperatively. The authors quantified (1) donor-site skeletal deformation with respect to the sixth to ninth costochondral junctions (2) and distortion in thoracic/hemithoracic Haller indices. The contralateral unoperated hemithorax provided intrapatient control data.
  
  
  RESULTS
  Statistically significant deformations occurred in the sagittal and transverse planes in growing patients and in the transverse plane in adults, with respect to most costochondral junctions on operated versus unoperated sides. Importantly, in growing patients, the sixth to ninth costochondral junctions on the operated side failed to descend postoperatively with normal growth in the vertical plane, unlike on the unoperated side. However, no gross distortions in thoracic/hemithoracic proportions occurred according to Haller indices.
  
  
  CONCLUSIONS
  Despite meticulous donor-site management and reconstruction according to the Kawanabe-Nagata method, patients sustained significant localized skeletal deformations, as quantified by three-dimensional computed tomography, the configurations of which differed according to whether patients were adult or growing when operated on. Whether these improve or worsen in the long term, particularly in growing patients, requires confirmation.
  
  
  METHODS
  Therapeutic, III.
authors.affiliation: Tao-Yuan, Taiwan; and Shantou, People's Republic of China From the Craniofacial Research Center, Division of Craniofacial Surgery, Department of Plastic Surgery, and the Department of Medical Imaging and Intervention, Chang-Gung Memorial Hospital, Chang Gung Medical College and University; and the Plastic Surgery and Burn Unit, Medical College, the Second Affiliated Hospital of Shantou University.
authors.forename: Christopher Glenn
authors.initials: CG
authors.lastname: Wallace
authors.forename: Hsiao-Yan
authors.initials: HY
authors.lastname: Mao
authors.forename: Chao-Jan
authors.initials: CJ
authors.lastname: Wang
authors.forename: Ying-An
authors.initials: YA
authors.lastname: Chen
authors.forename: Philip Kuo-Ting
authors.initials: PK
authors.lastname: Chen
authors.forename: Zung-Chung
authors.initials: ZC
authors.lastname: Chen
mesh_terms: D002356:Cartilage / Q000637:transplantation*; D002648:Child; D000013:Congenital Abnormalities / Q000000981:diagnostic imaging* / Q000601:surgery; D065817:Congenital Microtia; D004423:Ear / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional; D013902:Radiography, Thoracic; D019651:Plastic Surgery Procedures; D012272:Ribs / Q000000981:diagnostic imaging / Q000637:transplantation*; D013909:Thorax / Q000254:growth & development* / Q000473:pathology; D020858:Tissue and Organ Harvesting; D014057:Tomography, X-Ray Computed; D060053:Transplant Donor Site / Q000254:growth & development*; D014182:Transplantation, Autologous; D055815:Young Adult