Hepatocellular carcinoma treated with radio frequency ablation: an early evaluation with magnetic resonance imaging.
OBJECTIVE
To determine the usefulness of nonenhanced T1-weighted spoiled gradient-recalled acquisition in the steady-state (SPGR) MRI in the early assessment of the efficacy of radio frequency (RF) therapy for hepatocellular carcinoma (HCC).


METHODS
A total of 23 patients with 28 HCC nodules treated with percutaneous RF ablation underwent nonenhanced MRI within two days after the RF procedure and contrast-enhanced computed tomography (CT) one week after. MR assessment of ablation efficacy according to the concentric zonal pattern on T1-weighted SPGR imaging was compared with the one-week CT and presence of local recurrence by means of follow-up study for 12 months or more.


RESULTS
In 18 of 28 ablated nodules, SPGR images revealed a central hyperintense zone covering the entire tumor, CT showed a nonenhanced area covering the entire tumor, and no local recurrence was demonstrated in the follow-up studies. In nine of 28 nodules, the central hyperintense zone did not cover the entire tumor; and local recurrence was demonstrated in three nodules. In the remaining one nodule, no signal change was seen in the treated area on SPGR images and CT showed the presence of residual viable tumor.


CONCLUSIONS
Nonenhanced T1-weighted MRI was considered useful for early assessment of the efficacy of RF therapy for HCC.
Khankan
Azzam A
AA
Department of Radiology, Damascus University Hospital, Damascus, Syria.
Murakami
Takamichi
T
Onishi
Hiromitsu
H
Matsushita
Masaki
M
Iannaccone
Riccardo
R
Aoki
Yoshiko
Y
Tono
Takeshi
T
Kim
Tonsok
T
Hori
Masatoshi
M
Osuga
Keigo
K
Passariello
Roberto
R
Nakamura
Hironobu
H
D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome