title: Three-dimensional venous visualization with phase-lag computed tomography angiography for reconstructive microsurgery.
abstract: BACKGROUND
  Most free flap reconstruction complications involve vascular compromise. Evaluation of vascular anatomy provides considerable information that can potentially minimize these complications. Previous reports have shown that contrast-enhanced computed tomography is effective for understanding three-dimensional arterial anatomy. However, most vascular complications result from venous thromboses, making imaging of venous anatomy highly desirable.
  
  
  METHODS
  The phase-lag computed tomography angiography (pl-CTA) technique involves 64-channel (virtually, 128-channel) multidetector CT and is used to acquire arterial images using conventional CTA. Venous images are three-dimensionally reconstructed using a subtraction technique involving combined venous phase and arterial phase images, using a computer workstation.
  
  
  RESULTS
  This technique was used to examine 48 patients (12 lower leg reconstructions, 34 head and neck reconstructions, and 2 upper extremity reconstructions) without complications. The pl-CTA technique can be used for three-dimensional visualization of peripheral veins measuring approximately 1 mm in diameter.
  
  
  CONCLUSIONS
  The pl-CTA information was especially helpful for secondary free flap reconstructions in the head and neck region after malignant tumor recurrence. In such cases, radical dissection of the neck was performed as part of the first operation, and many vessels, including veins, were resected and used in the first free-tissue transfer. The pl-CTA images also allowed visualization of varicose changes in the lower leg region and helped us avoid selecting those vessels for anastomosis. Thus, the pl-CTA-derived venous anatomy information was useful for exact evaluations during the planning of free-tissue transfers.
authors.affiliation: Department of Plastic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Sakakibara
authors.affiliation: Kobe Circulation Clinic, Kobe, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Onishi
authors.affiliation: Department of Plastic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Hashikawa
authors.affiliation: Department of Oral Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Akashi
authors.affiliation: Department of Oral Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Sakakibara
authors.affiliation: Department of Plastic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nomura
authors.affiliation: Department of Plastic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Terashi
mesh_terms: D000714:Anastomosis, Surgical; D015901:Angiography, Digital Subtraction / Q000379:methods*; D003287:Contrast Media; D058752:Free Tissue Flaps; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007866:Leg / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery; D008866:Microsurgery; D010690:Phlebography / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted; D019651:Plastic Surgery Procedures; D014057:Tomography, X-Ray Computed / Q000379:methods*; D034941:Upper Extremity / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery
chemical_list: D003287:Contrast Media