Radiofrequency ablation of normal lungs after pulmonary artery embolization with use of degradable starch microspheres: results in a porcine model.
OBJECTIVE
The present study was performed to evaluate the effect of pulmonary artery embolization on radiofrequency (RF) ablation of normal porcine lungs.


METHODS
RF ablation zones (n=34) were created in the normal lungs of five domestic pigs (five zones in each of the first two pigs and eight zones in each of the remaining three pigs) with an expandable multitined electrode with use of bilateral thoracotomy. RF ablation was performed without pulmonary artery embolization (group 1, n=8), immediately after embolization (group 2, n=11), 15 minutes after embolization (group 3, n=7), and 30 minutes after embolization (group 4, n=8) with degradable starch microspheres. Among them, 12 ablation zones were excluded from this study because they were considerably limited by the presence of the pleura or large bronchi. The remaining 22 zones were included (n=7, n=5, n=4, and n=6 in groups 1, 2, 3, and 4, respectively). Coagulation necrosis volumes in the ablation zones were measured and compared among the groups.


RESULTS
Coagulation necrosis volumes were 0.9+/-0.5 cm3, 2.1+/-0.4 cm3, 2.1+/-1.0 cm3, and 1.9+/-0.6 cm3 in groups 1, 2, 3, and 4, respectively. Groups 2-4 showed significantly larger coagulation volumes than group 1 (P=.012, P=.023, and P=.010 in groups 2, 3, and 4, respectively).


CONCLUSIONS
Pulmonary artery embolization contributed to larger volumes of coagulation necrosis after RF ablation of normal lungs.
Hiraki
Takao
T
Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Okayama 700-8558, Japan. takaoh@tc4.so-net.ne.jp
Gobara
Hideo
H
Sakurai
Jun
J
Mimura
Hidefumi
H
Mukai
Takashi
T
Hase
Soichiro
S
Iguchi
Toshihiro
T
Fujiwara
Hiroyasu
H
Tajiri
Nobuhisa
N
Yanai
Hiroyuki
H
Yoshino
Tadashi
T
Kanazawa
Susumu
S
D000818:Animals; D017115:Catheter Ablation; D004621:Embolization, Therapeutic / Q000379:methods*; D008168:Lung / Q000601:surgery*; D023421:Models, Animal; D009336:Necrosis; D011651:Pulmonary Artery; D013213:Starch; D018709:Statistics, Nonparametric; D034421:Sus scrofa
C083286:degradable starch microspheres; D013213:Starch