title: Temporal changes in the stiffness of the remnant liver and spleen after donor hepatectomy as assessed by acoustic radiation force impulse: A preliminary study.
abstract: OBJECTIVE
  Virtual touch tissue quantification (VTTQ) is an implementation of ultrasound acoustic radiation force impulse imaging that provides numerical measurements of tissue stiffness. We have evaluated the temporal changes of the remnant liver and spleen after living donor hepatectomy with special reference to the differences between right and left liver donation.
  
  
  METHODS
  Nineteen living donors who received right lobectomy (small remnant liver [SRL] group; n = 7) or extended left and caudate lobectomy (large remnant liver [LRL] group; n = 12) were enrolled. They underwent measurement of liver and spleen VTTQ before and after donor surgery.
  
  
  RESULTS
  Virtual touch tissue quantification of the remnant liver increased postoperatively until postoperative day (POD) 3-5, and the values in the SRL group were significantly higher than those in the LRL group at POD 3-9. The values of the spleen also increased after donor surgery and the values in the SRL group were significantly higher than those in the LRL group at POD 3-14. A significant positive correlation between postoperative maximum value of VTTQ and postoperative maximum total bilirubin levels was observed. In liver transplant recipients, there was a significant positive correlation between preoperative spleen VTTQ and the corresponding actual portal venous pressure that was measured at the time of transplant surgery.
  
  
  CONCLUSIONS
  Stiffness of the remaining liver and spleen in the smaller remnant liver group became harder than that in the larger remnant liver group. Perioperative measurement of liver and spleen VTTQ seems to be a useful means for assessing the physiology of liver regeneration.
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Mizuki
authors.initials: M
authors.lastname: Ninomiya
authors.forename: Ken
authors.initials: K
authors.lastname: Shirabe
authors.forename: Hideki
authors.initials: H
authors.lastname: Ijichi
authors.forename: Takeo
authors.initials: T
authors.lastname: Toshima
authors.forename: Noboru
authors.initials: N
authors.lastname: Harada
authors.forename: Hideaki
authors.initials: H
authors.lastname: Uchiyama
authors.forename: Akinobu
authors.initials: A
authors.lastname: Taketomi
authors.forename: Tomoharu
authors.initials: T
authors.lastname: Yoshizumi
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Maehara