title: A Study of Internal Thoracic Arteriovenous Principal Perforators by Using Multi-detector Row Computed Tomography Angiography.
abstract: OBJECTIVE
  There are numerous reports of perforating branches from the intercostal spaces of the internal thoracic vessels. These branches have varying diameters, and a main perforating branch, the principal perforator, most often found in the second or third intercostal space. We report different results based on multi-detector row computed tomography.
  
  
  METHODS
  We evaluated 121 sides from 70 women scheduled for breast reconstruction with free lower abdominal skin flaps who underwent preoperative multi-detector row computed tomographic scan between June 2008 and June 2015. For primary reconstruction, we analyzed both sides, and for 1-sided secondary reconstruction, we analyzed only the unaffected side. We evaluated both early arterial phase and late venous phase 5-mm horizontal, cross-sectional, and volume-rendering images for perforation sites and internal thoracic arteriovenous perforating branches' intercostal space thickness. We analyzed differences in thickness between the internal thoracic arteries and veins and symmetry in cases involving both sides.
  
  
  RESULTS
  Venous principal perforators nearly always perforated the same intercostal spaces as accompanying veins of arterial principal perforators (99.2%), forming arteriovenous principal perforators. We found 49 principal perforators in the first intercostal space (37.4%), 52 in the second intercostal space (39.7%), 23 in the third intercostal space (17.6%), 6 in the fourth intercostal space (4.6%), and 1 in the fifth intercostal space (0.7%). Of the 51 cases in which we studied both sides, 25 cases (49%) had principal perforators with bilateral symmetry.
  
  
  CONCLUSIONS
  In contrast to findings from past reports, we found that internal thoracic arteriovenous principal perforators were often present in almost the same numbers in the first and second intercostal spaces.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kobe University Graduate School of Medicine, Hyogo, Kobe, Japan; Department of Plastic and Reconstructive Surgery, Shinko Hospital, Hyogo, Kobe, Japan.
authors.forename: Ko
authors.initials: K
authors.lastname: Okumura
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kobe University Graduate School of Medicine, Hyogo, Kobe, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Hashikawa
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kobe University Graduate School of Medicine, Hyogo, Kobe, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Sakakibara
authors.affiliation: Kobe Cardiovascular Clinic, Hyogo, Kobe, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Onishi
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kobe University Graduate School of Medicine, Hyogo, Kobe, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Terashi
keywords: anatomy; breast reconstruction; internal mammary perforators; multi-detector row computed tomography angiography; principal perforator