title: Layers of the abdominal wall: anatomical investigation of subcutaneous tissue and superficial fascia.
abstract: BACKGROUND
  In recent times new surgical approaches have been developed, in which subcutaneous tissue is the primary object, such as flaps and fat removal techniques, but different descriptions and abundance of terminology persist in Literature about this tissue.
  
  
  OBJECTIVE
  In order to investigate the structure of abdominal subcutaneous tissue, macroscopic and microscopic analyses of its layers were performed in 10 fresh cadavers. Results were compared with in vivo CT images of the abdomen of 10 subjects.
  
  
  RESULTS
  The subcutaneous tissue of the abdomen comprises three layers: a superficial adipose layer (SAT), a membranous layer, and a deep adipose layer (DAT). The SAT presented fibrous septa that defined polygonal-oval lobes of fat cells with a mean circularity factor of 0.856 ± 0.113. The membranous layer is a continuous fibrous membrane rich in elastic fibers with a mean thickness of 847.4 ± 295 μm. In the DAT the fibrous septa were predominantly obliquely-horizontally oriented, defining large, flat, polygonal lobes of fat cells (circularity factor: mean 0.473 ± 0.07). The CT scans confirm these findings, showing a variation of the thickness of the SAT, DAT and membranous layer according with the subjects and with the regions.
  
  
  CONCLUSIONS
  The distinction of SAT and DAT and their anatomic differences are key elements in modern approaches to liposuction. The membranous layer appears to be also a dissection plane which merits further attention. According with the revision of Literature, the Authors propose that the term "superficial fascia" should only be used as a synonym for the membranous layer.
authors.affiliation: Department of Medical-Surgical Specialities, Institute of Plastic Surgery, University of Padova, via Giustiniani 2, 35128, Padova, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Lancerotto
authors.forename: Carla
authors.initials: C
authors.lastname: Stecco
authors.forename: Veronica
authors.initials: V
authors.lastname: Macchi
authors.forename: Andrea
authors.initials: A
authors.lastname: Porzionato
authors.forename: Antonio
authors.initials: A
authors.lastname: Stecco
authors.forename: Raffaele
authors.initials: R
authors.lastname: De Caro
mesh_terms: D034861:Abdominal Wall / Q000033:anatomy & histology*; D000368:Aged; D000369:Aged, 80 and over; D005205:Fascia / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D050507:Subcutaneous Fat, Abdominal / Q000033:anatomy & histology* / Q000000981:diagnostic imaging