Liver function after irradiation based on computed tomographic portal vein perfusion imaging.
OBJECTIVE
To determine whether individual and regional liver sensitivity to radiation could be assessed by measuring liver perfusion during a course of treatment using dynamic contrast-enhanced computed tomography scanning.


METHODS
Patients with intrahepatic cancer undergoing conformal radiotherapy underwent dynamic contrast-enhanced computed tomography (to measure perfusion distribution) and an indocyanine extraction study (to measure liver function) before, during, and 1 month after treatment. We hoped to determine whether the residual functioning liver (i.e., those regions showing portal vein perfusion) could be used to predict overall liver function after irradiation.


RESULTS
Radiation doses from 45 to 84 Gy resulted in undetectable regional portal vein perfusion 1 month after treatment. The volume of each liver with undetectable portal vein perfusion ranged from 0 to 39% and depended both on the patient's sensitivity and on dose distribution. There was a significant correlation between indocyanine green clearance and the mean of the estimated portal vein perfusion in the functional liver parenchyma (p < 0.001).


CONCLUSIONS
This study reveals substantial individual variability in the sensitivity of the liver to irradiation. In addition, these findings suggest that hepatic perfusion imaging may be a marker for liver function and has the potential to be a tool for individualizing therapy.
Cao
Yue
Y
Department of Radiation Oncology, University of Michigan, UH-B2C432, Box 0010, Ann Arbor, MI 48109-0010, USA. yuecao@umich.edu
Pan
Charlie
C
Balter
James M
JM
Platt
Joel F
JF
Francis
Isaac R
IR
Knol
James A
JA
Normolle
Daniel
D
Ben-Josef
Edgar
E
Ten Haken
Randall K
RK
Lawrence
Theodore S
TS
D000328:Adult; D000368:Aged; D003287:Contrast Media; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D007208:Indocyanine Green; D008099:Liver / Q000098:blood supply* / Q000503:physiopathology / Q000528:radiation effects*; D008111:Liver Function Tests / Q000379:methods; D008113:Liver Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011836:Radiation Tolerance; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D007208:Indocyanine Green