title: Evaluation of postoperative damage to anal sphincter/levator ani muscles with three-dimensional vector manometry after sphincter-preserving operation for rectal cancer.
abstract: BACKGROUND
  The aim of this study was to examine correlations between pressure profile of the anal canal and postoperative defecatory disorder after sphincter-preserving operation (SPO) for rectal cancer.
  
  
  METHODS
  Using three-dimensional vector manometry, pressure profile and length of the anal canal were evaluated more than 1 year after SPO according to operation method and degree of postoperative defecatory function in 53 patients with rectal cancer.
  
  
  RESULTS
  Compared with high anterior resection as a control, the anal canal was shorter in operations with a pelvic floor maneuver, namely, low anterior resection, ultra-low anterior resection, and intersphincteric resection. Patients with postoperative defecatory disorder showed significantly shorter anal canal length than patients with fair function. Length of the circular high-pressure zone (> or = 20 mmHg) < 20 mm in the resting state was a strong predictor of severe postoperative defecatory malfunction, with Wexner score> or =10.
  
  
  CONCLUSIONS
  Operative maneuvers at the pelvic floor during SPO for rectal cancer may damage anal sphincter or levator ani muscles. The circular high-pressure zone can be measured only by three-dimensional manometry and may offer a useful indicator of sphincter damage after SPO for rectal cancer.
authors.affiliation: Department of Surgery, Teikyo University Chiba Medical Center, Ichihara City, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Koda
authors.forename: Hideki
authors.initials: H
authors.lastname: Yasuda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hirano
authors.forename: Chihiro
authors.initials: C
authors.lastname: Kosugi
authors.forename: Masato
authors.initials: M
authors.lastname: Suzuki
authors.forename: Masato
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Tohru
authors.initials: T
authors.lastname: Tezuka
authors.forename: Ryota
authors.initials: R
authors.lastname: Higuchi
authors.forename: Hironori
authors.initials: H
authors.lastname: Tsuchiya
authors.forename: Norio
authors.initials: N
authors.lastname: Saito