title: Histologic comparison between the internal mammary artery and the deep inferior epigastric artery and clinical implications for microsurgical breast reconstruction.
abstract: BACKGROUND
  The internal mammary artery (IMA) is one of the most popular recipients for microsurgical breast reconstruction. However, it is often separated into sleeve-like layers when it is handled. This study tried to explain this unique behaviour of the IMA through histologic observation.
  
  
  METHODS
  Nine pairs of IMAs and DIEAs were harvested and subject for haematoxylin-eosin and Verhoeff's elastic staining. Thickness of the tunica media and the number of elastic lamellae were compared. Samples of the IMA, the DIEA, and the thoracodorsal artery from another patient were observed through the transmission electron microscope to further show the structural differences.
  
  
  RESULTS
  The most notable difference was presence of multiple elastic lamellae in tunica media in the IMAs, which was barely present in the DIEAs. The mean number of elastic lamellae was 9.2 in the IMA group and 1.0 in the DIEA group (p < 10(-9)). A transmission electron microscope showed that the tunica media of the DIEA and the TDA was densely packed with smooth muscle cells, while the muscle cells distributed sparsely in the IMA.
  
  
  CONCLUSIONS
  The IMA is an elastic artery which is characterised by multiple layers of elastic lamellae while relatively lacking in smooth muscle cells. The wall of the IMA is easily dissected between the tunica media and the adventitia, or at the outer 1/3 of the tunica media. The inner structure is easily torn if microsutures do not engage the tunica adventitia.
authors.affiliation: Department of Plastic Surgery, Asan Medical Center, University of Ulsan, College of Medicine , Seoul , Korea.
authors.forename: Woo Shik
authors.initials: WS
authors.lastname: Jeong
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Yun
authors.forename: Taik Jong
authors.initials: TJ
authors.lastname: Lee
authors.forename: Jin Sup
authors.initials: JS
authors.lastname: Eom
authors.forename: Eun Key
authors.initials: EK
authors.lastname: Kim
mesh_terms: D000328:Adult; D004547:Elastic Tissue / Q000648:ultrastructure; D019074:Epigastric Arteries / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D016462:Mammaplasty; D008323:Mammary Arteries / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D008866:Microsurgery; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000166:cytology; D017540:Tunica Media / Q000648:ultrastructure
keywords: deep inferior epigastric artery; internal mammary artery; microsurgery; tunica media