Percutaneous microwave coagulation for recanalizing stents occluded by tumor ingrowth
has been reported. With this technique, however, the percutaneous drain diminishes
the quality of life in patients with unresectable tumors and a limited prognosis.
Transpapillary microwave ablation was attempted in three patients with occluded stents.
After a sheath had been inserted into the proximal hepatic duct across the occluded
region, a microwave electrode was introduced into the intrahepatic duct via the sheath.
We used microwave therapy with an output power of 40 W, based on our previous in vitro
study. Except in one patient, the stents were successfully recanalized with one or
two attempts. In one patient who underwent ablation in the intrahepatic duct, a 1.8-mm
electrode enabled recanalization of the stent. In another who underwent ablation in
the extrahepatic duct, however, a larger electrode was required. There were no procedure-related
complications. Transpapillary microwave coagulation of occluded stents appears to
be an alternative to percutaneous microwave coagulation with an electrode fitting
the stent size. The technique might be easier with the use of a redesigned electrode
with a guide wire lumen.
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in press
I. Maetani,M.D.
Third Dept. of Internal Medicine
Toho University School of Medicine
Ohashi Hospital
2-17-6 Ohashi Meguro-ku
Tokyo 153-8515
Japan
Fax: + 81-3-34681269
Email: maet@oha.toho-u.ac.jp