Detection of hypovascular hepatic metastases at triple-phase helical CT: sensitivity of phases and comparison with surgical and histopathologic findings.
OBJECTIVE
To compare the respective sensitivities of unenhanced, arterial-dominant, and portal-dominant phase helical computed tomography (CT) in the preoperative depiction of hypovascular hepatic metastases by using intraoperative ultrasonographic (US) and histopathologic findings as the standard of reference.


METHODS
In this prospective study, 32 patients with 59 surgically and histopathologically proved hypovascular hepatic metastases underwent triple-phase helical CT of the liver, which included unenhanced, arterial-dominant, and portal-dominant phase scanning. Images from each phase were separately analyzed by three readers, and disagreements were resolved with consensus readings. The findings on CT images were compared with intraoperative US and histopathologic findings on a lesion-by-lesion basis to determine the sensitivity of each imaging phase. Statistical review of the lesion-by-lesion analysis was performed by using the Wilcoxon rank sum test.


RESULTS
Among 59 hepatic metastases, unenhanced, arterial-dominant, and portal-dominant phase helical CT imaging depicted 39 (66.1%; 95% CI: 53.3%, 76.8%), 44 (74.5%; 95% CI: 62.2%, 83.9%), and 54 (91.5%; 95% CI: 81.6%, 96.3%) metastases, respectively. Portal-dominant phase imaging depicted significantly more hypovascular hepatic metastases than did unenhanced (P <.001) or arterial-dominant (P <.01) phase imaging (Wilcoxon test).


CONCLUSIONS
Preoperative use of triple-phase helical CT in patients with hypovascular hepatic metastases may not be warranted. Portal-dominant phase helical CT imaging allows depiction of significantly more hypovascular hepatic metastases than does imaging during any of the other phases.
Soyer
Philippe
P
Department of Radiology, Hôpital Lariboisière-AP-HP, 2 rue Ambroise Paré, 75475 Paris cedex 10, France. philippe.soyer@lrb.ap-hop-paris.fr
Poccard
Marc
M
Boudiaf
Mourad
M
Abitbol
Martine
M
Hamzi
Lounis
L
Panis
Yves
Y
Valleur
Patrice
P
Rymer
Rolland
R
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed