title: Retroportal lamina or mesopancreas? Lessons learned by anatomical and histological study of thirty three cadaveric dissections.
abstract: OBJECTIVE
  Despite its importance in pancreatic head carcinoma, the retroportal lamina is still under studied, with only two anatomical cadaveric dissections in the English literature, with recent controversies about the concept of a mesopancreas.
  
  
  METHODS
  Resection of the mesopancreas was performed in 33 fresh cadavers. The pancreas and mesopancreas were separated from each other and the mesopancreas was immunohistochemically investigated.
  
  
  RESULTS
  The retroportal lamina is roughly rectangular in shape. Its dimensions are: height 6.2 cm (5-8), 2.5 cm wide (1.5-4). It contains a right hepatic artery arising from the superior mesenteric artery in 13.3% of cases. Microscopic examination revealed areolar tissue, adipose tissue, peripheral nerve, nerve plexus, lymphatics and capillaries. However, fibrous sheath and fascia were not found around these structures.
  
  
  CONCLUSIONS
  A right hepatic artery arising from the superior mesenteric artery is a frequent anatomic variation. Surgeons must be aware of this to ensure the integrity of the hepatic artery blood supply in patients treated by pancreaticoduodenectomy. Despite controversy about the reality of the mesopancreas (postulated in analogy to the mesorectum), because of the absence of fibrous sheath or fascia, its complete removal in pancreatic head carcinoma is feasible by a subadventitial dissection of the superior mesenteric artery which can be considered as the real limit of the mesopancreas.
authors.affiliation: Department of Surgery, Mohamed Tahar Maamouri Hospital, Mrezga, 8000 Nabeul, Tunisia; Université Tunis-El Manar, Faculté de Médecine de Tunis, 15, rue Djebel Akhdhar, Tunis, Tunisia. Electronic address: bouassidamahdi@yahoo.fr.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Bouassida
authors.forename: Mohamed Mongi
authors.initials: MM
authors.lastname: Mighri
authors.forename: Mohamed Fadhel
authors.initials: MF
authors.lastname: Chtourou
authors.forename: Selim
authors.initials: S
authors.lastname: Sassi
authors.forename: Hassen
authors.initials: H
authors.lastname: Touinsi
authors.forename: Hassen
authors.initials: H
authors.lastname: Hajji
authors.forename: Sadok
authors.initials: S
authors.lastname: Sassi
mesh_terms: D000328:Adult; D000715:Anatomy / Q000193:education*; D002102:Cadaver; D004210:Dissection; D006499:Hepatic Artery / Q000033:anatomy & histology*; D006801:Humans; D017538:Mesenteric Artery, Superior / Q000033:anatomy & histology*; D010179:Pancreas / Q000033:anatomy & histology*
keywords: Mesopancreas; Pancreatic head carcinoma; Pancreaticoduodenectomy; Retroportal lamina; Right hepatic artery