[Radiofrequency ablation of rabbit liver: correlation between dual CT findings and pathological findings].
OBJECTIVE
To present the time-related imaging findings and correlative pathologic findings of radiofrequency pulse-irradiated regions of the liver.


METHODS
Radiofrequency (RF) ablation was performed in 22 rabbit livers with 15-gauge RF probes inserted percutaneously. Regions were imaged with dual-phase CT at 3 days (n = 6), 2 weeks (n = 6), 4 weeks (n = 6), and 12 weeks (n = 4) after RF ablation.


RESULTS
At 3 days, the regions showed a two-zone structure on plain CT and peripheral enhancement. The regions presented a three-zone structure on pathological study. Hepatocytes appeared as acidophilic bodies, and nuclei were pyknotic at the inner necrotic zone. The middle whitish zone showed enlarged sinusoids. The marginal zone was a regenerative band. At 2 weeks, the two-zone structure was obscured on unenhanced CT. The region showed a two-zone structure on pathological study. At the inner zone, acidophilic degeneration had progressed, however, cell structure remained. The marginal zone showed fibrous tissue bundles. At 12 weeks, the region was obscured on plain CT. Nuclei and cell structures had disappeared almost completely at the inner zone. Collagen fiber had replaced the marginal zone.


CONCLUSIONS
Zone structural CT findings reflect the pathological findings and time-related changes after RF ablation. Peripheral enhancement in the arterial phase reflects the granulation tissue layer, and its time-related decrease reflects replacement by fibrous tissue.
Tsuda
Masashi
M
Department of Radiology, National Sendai Hospital.
Rikimaru
Yuya
Y
Saito
Haruo
H
Ishibashi
Tadashi
T
Takahashi
Shyoki
S
Miyachi
Hideo
H
Yamada
Syogo
S
D000818:Animals; D017115:Catheter Ablation / Q000009:adverse effects; D005355:Fibrosis / Q000000981:diagnostic imaging / Q000473:pathology; D006097:Granulation Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D006499:Hepatic Artery / Q000000981:diagnostic imaging / Q000473:pathology; D022781:Hepatocytes / Q000000981:diagnostic imaging / Q000473:pathology; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology*; D011817:Rabbits; D013997:Time Factors; D014057:Tomography, X-Ray Computed