title: Histologic Evaluation of Lymphaticovenular Anastomosis Outcomes in the Rat Experimental Model: Comparison of Cases with Patency and Obstruction.
abstract: BACKGROUND
  Lymphaticovenular anastomosis plays an important role in the surgical treatment of lymphedema. The outcomes of lymphaticovenular anastomosis are evaluated based on changes in edema; however, isolated assessment of the anastomosis itself is difficult. The authors used an animal experimental model to conduct a detailed examination of histologic changes associated with lymphaticovenular anastomosis and determined the factors important for success.
  
  
  METHODS
  The experimental lymphaticovenular anastomosis model was created using lumbar lymph ducts and iliolumbar veins of Wistar rats. The authors performed anastomosis under a microscope and reviewed postoperative histologic changes using optical and electron microscopy. In addition, electron microscopy and histology were used for detailed examination of the area in the vicinity of the anastomotic region in cases with patency and obstruction.
  
  
  RESULTS
  The patency rates immediately after, 1 week after, and 1 month after lymphaticovenular anastomosis were 100 percent (20 of 20), 70 percent (14 of 20), and 65 percent, respectively. A detailed examination of the anastomotic region with electron microscopy revealed that, in cases with patency, there was no notable transformation of the endothelial cells, which formed a smooth layer. In contrast, in obstruction cases, the corresponding region of the endothelium was irregular in structure.
  
  
  CONCLUSIONS
  Vessel obstruction after lymphaticovenular anastomosis may be associated with irregular arrangement of the endothelial layer, leading to exposure of subendothelial tissues and platelet formation. One part of the postoperative changes after anastomosis and a cause of obstruction were elucidated in this study. The authors' results may enable improvements in lymphaticovenular anastomosis by translating back to real clinical operations.
authors.affiliation: Okayama, Japan From the Department of Plastic and Reconstructive Surgery, Graduate School of Medicine, Dentistry, and Pharmaceutical Science, University of Okayama.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Onoda
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kimata
authors.forename: Kumiko
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Yamada
authors.forename: Eijiro
authors.initials: E
authors.lastname: Tokuyama
authors.forename: Narushi
authors.initials: N
authors.lastname: Sugiyama
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D000818:Animals; D003251:Constriction, Pathologic / Q000473:pathology; D004195:Disease Models, Animal; D007084:Iliac Vein / Q000601:surgery* / Q000648:ultrastructure; D035002:Lower Extremity / Q000098:blood supply; D042601:Lymphatic Vessels / Q000601:surgery* / Q000648:ultrastructure; D008209:Lymphedema / Q000473:pathology / Q000601:surgery*; D008297:Male; D008854:Microscopy, Electron; D008866:Microsurgery / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome; D014654:Vascular Patency / Q000502:physiology*; D014656:Vascular Surgical Procedures / Q000379:methods*