Microwave coagulation therapy with interruption of hepatic blood in- or outflow: an experimental study.
OBJECTIVE
To determine how interruption of hepatic blood in- or outflow affects the coagulation diameter of microwave coagulation therapy (MCT) in the liver.


METHODS
Laparotomic MCT at 60 W for 1 minute was performed in 11 Landrace pigs. MCT was performed under six different conditions: without occlusion (Group N; in seven lobes of seven pigs); with occlusion of the hepatic artery (Group A; in five lobes of five pigs); with occlusion of the portal vein (Group P; in five lobes of five pigs); with occlusion of the hepatic artery and portal vein (Group AP; in six lobes of six pigs); with occlusion of the hepatic vein (Group V; in five lobes of four pigs); and with occlusion of the hepatic artery and vein (Group AV; in seven lobes of seven pigs). The maximum diameters for each group were compared.


RESULTS
The coagulation diameters (mean +/- SD) were 8.5 mm +/- 2.0, 10.0 mm +/- 1.6, 14.3 mm +/- 2.5, 14.4 mm +/- 2.4, 13.0 mm +/- 0.8, and 14.4 mm +/- 1.5 for Groups N, A, P, AP, V, and AV, respectively. The coagulation diameters for groups P, AP, V, and AV were statistically larger than those for groups N and A (P < .05). There was no significant difference between the coagulation diameters of Groups P, AP, V, and AV.


CONCLUSIONS
The coagulation diameter depends mainly on the portal venous flow. In addition of direct interruption of the portal vein, interruption of the hepatic vein can also result in a substantial increase in the coagulation diameter.
Takamura
M
M
Department of Radiology, Osaka University Medical School, Suita City, Osaka, Japan. takamura@radiol.med.osaka-u.ac.jp
Murakami
T
T
Shibata
T
T
Ishida
T
T
Niinobu
T
T
Kawata
S
S
Shimizu
J
J
Kim
T
T
Monden
M
M
Nakamura
H
H
D000818:Animals; D004564:Electrocoagulation / Q000379:methods; D005260:Female; D006499:Hepatic Artery / Q000502:physiology; D006503:Hepatic Veins / Q000502:physiology; D007813:Laparotomy; D008099:Liver / Q000601:surgery*; D008102:Liver Circulation / Q000502:physiology*; D008872:Microwaves / Q000627:therapeutic use*; D011168:Portal System / Q000502:physiology; D013552:Swine