Jpn J Intervent Radiol Vol.21 No.3 2006

State of the Art
Minimally Invasive Therapy-Radiofrequency Tumor Ablation

1.Radiofrequency Ablation for Liver Tumor :Indication, Effectiveness, and Complications
Department of Radiology, Kyoto University Graduate School of Medicine
Toshiya Shibata, Masahiro Hiraoka

Image-guided tumor ablation has been an accepted minimally-invasive therapy for malignant tumors. Of several ablation procedures, radiofrequency ablation (RFA) has been most widely performed. In Japan, internally-cooled electrode and expandable electrode are commercially available. RFA is very effective for small hepatocellular carcinoma (HCC) < 3b and survival of patients with small HCC treated by RFA is comparable to that of patients who underwent hepatectomy. Although RFA is safe and major complications are rarely seen, liver abscess, perforation of gastrointestinal tracts, or tumor implantation might be fatal in some cases. RFA has been an established treatment of small HCC.

Key words
● Radiofrequency ablation
● Liver tumor
● Hepatocellular carcinoma

2.Radiofrequency Ablation for Lung Cancer ―How to Do It―
Department of Radiology and Cancer and Thoracic Surgery1), Okayama University Medical School
Hideo Gobara, Takashi Mukai, Hidefumi Mimura, Takao Hiraki
Yoshifumi Sano1), Hiroshi Date1), Susumu Kanazawa

Primary and secondary lung cancer is worldwide problem, however, many patients are non-surgical candidates for comorbidity. Percutaneous radiofrequency ablation(RFA) is a newly developed therapeutic option for unresectable lung cancer. Several authors have reported preliminary results of this therapy, including usefulness, low complication rates, and minimal hospitalization. But its technique and ablation algorithm are not well established. RFA for lung cancer has been performed at Okayama University under approval of institutional review board since Jun 2001. Total of 227 patients with 639 tumors were treated at the end of April 2006. Primary and secondary technique effectiveness rates at 3-year is 53% and 64%, respectively. In this article, we show our experience of RFA for lung cancer, including indication, ablation planning, techniques, results, complications, and its future.

Key words
● Ablation
● Lung cancer
● Radiofreguency

3.Radiofrequency Ablation for Renal Neoplasms
Department of Radiology and Urology1), Mie University Graduated School of Medicine
Koichiro Yamakado, Haruyuki Takaki, Atsuhiro Nakatsuka
Kan Takeda, Kiminobu Arima1), Yoshiki Sugimura1)

Recent advances in percutaneous radiofrequency (RF) ablation have opened new perspectives in the treatment of unresectable renal neoplasms. Technical effectiveness is as high as 79~100%. Results are excellent for small tumors (3b or less), but successful treatment is less likely as tumor size increases or the location becomes more central. Major complications usually occur in fewer than 10% of procedures and are rarely associated with mortality. Although patient series is still small, recent studies have suggested good prognosis of selected patients with unresectable renal cell carcinomas who received renal RF ablation.

Key words
● Radiofrequency ablation
● Renal neoplasmas

4.Percutaneous Radiofrequency Ablation Therapy for Painful Metastatic Bone Tumor
Department of Radiology, Kansai Medical University Hirakata Hospital
Noboru Tanigawa, Shuji Kariya, Atsushi Komemushi, Yuzo Shomura, Satoshi Sawada
Department of Radiology, Kansai Medical University Takii Hospital
Hiroyuki Kojima

In recent years, radiofrequency ablation (RFA) has started to be performed not only for the treatment of liver tumors, but also for lung, kidney, adrenal, bone and soft-tissue tumors, and the efficacy of this technique has been reported. For patients with painful metastatic bone tumors in whom other methods of pain relief have proved ineffective, RFA may represent a useful alternative for alleviating pain. In this paper, we describe our method of percutaneous radiofrequency ablation of painful metastatic bone tumor and our clinical results.

Key words
● Radiofrequency ablation
● Bone metastases
● Interventional procedure

5.Palliative Treatment Using Radiofrequency Ablation for Cancer Associated Pain
of Soft Tissue Malignancy

Department of Diagnostic and Interventional Radiology, Shitennnoji Hospital
Hiroshi Anai
Department of Radiology, Nara Medical University
Hiroshi Sakaguchi, Kimihiko Kichikawa

It is very important to relieve cancer associated pain of patients with advanced cancer to improve their quality of life. Radiofrequency ablation (RFA) has been a promising therapy for focal malignancy of liver, lung, kidney and so on. And several studies reported the efficacy of RFA for pain of bone metastasis, osteoid osteoma and others. This article describes the therapeutic systems and technique, and complications of RFA for cancer associated pain of soft tissue tumors, especially intrapelvic tumors.
It is suggested that RFA is effective for cancer associated pain of soft tissue tumor. However, in the procedure of RFA, we have to take care of the adjacent tissue (skin, rectum, urinary bladder, urethra, uterious and so on) to avoid thermal injury to them.

Key words
● Radiofreguency ablation
● Palliative treatment
● Cancer associated pain

6.Percutaneous Radiofrequency Ablation for Osteoid Osteoma
Diagnostic and Interventional Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine
Masaya Miyazaki, Satoshi Hirasawa, Ayako Takahashi, Takahito Nakajima, Makoto Amanuma, Keigo Endo
Department of Radiology, Gunma General Hospital
Jun Aoki
Department of Radiology and Orthopaedic Surgery1), Gunma University Hospital
Hideo Morita, Yoshinori Koyama, Tetsuya Shinozaki

Osteoid osteoma is a benign bone tumor typically less than 2b in size. These lesions are difficult to identify precisely ; this can necessitate substantial resection of the surrounding normal bone. Recently, radiofrequency ablation (RFA) has been used for the treatment of osteoid osteoma, and satisfactory clinical results have been reported. However, the clinical benefit of RFA for osteoid osteoma has not yet been established. In this report we demonstrate the basic concepts and clinical applications, and evaluate the technical safety and efficacy of this procedure. Since February 2002, 10 osteoid osteomas were treated using percutaneous RFA with cooled RFA needle (Cool-tip) in our institution. The procedure was performed under CT guidance after general or spinal anesthesia. A 14-gauge core needle was introduced into the nidus and then exchanged for a 17-gauge straight rigid electrode with a 1-b exposed tip to heat the lesion to 90 degrees centigrade for 5 minutes.
In all cases the procedure was successful. Nine patients reported complete resolution of pain and one patient reported a significant decrease of pain. Complications included broken biopsy needle, intramuscular hemorrhage, and pes equines, but there were no severe complications. There was recurrence in one patient, but pain resolved after a repeat RFA.
Percutaneous radiofrequency ablation of osteoid osteoma is a highly effective, efficient, minimally invasive and safe method of treating osteoid osteoma.

Key words
● Osteoid osteoma
● Radiofrequency ablation
● Computed tomography-guided

7.Radiofrequency Ablation Therapy for Breast Cancer
Department of Thoracic and Cardiovaascular Surgery, Wakayama Medical University
Shoji Oura

We report our technique and short-term results of radiofrequency ablation therapy (RFA) for breast cancer. RFA for breast cancer consists of insertion of RFA-needle into tumor under ultrasound guidance, subcutaneous injection of 5% glucose, delivery of radiofrequency, icing of skin just above the tumor, and evaluation of temperature of the tumor. RFA-induced burn of the skin was observed in three cases (2%). Of the 102 patients receiving RFA, none developed in-breast recurrence for an average of 11 months (range, 1~30 months). Only one of the 41 patients receiving RFA after primary systemic therapy developed in-breast recurrence, which was successfully managed with re-RFA to the recurrence. Cosmesis of the breasts after RFA was excellent. These results suggest that RFA is a promising alternative to partial mastectomy in breast cancer.

Key words
● Breast cancer
● Radiofrequency ablation

Original Articles
Stent-graft Placement for the Treatment of Solitary Internal Iliac Artery Aneurysms : Significance of Preceding Embolization of Distal Internal Iliac Artery
Department of Diagnostic Radiology, and Cardiovascular Surgery1)
Kumamoto University Graduate School of Medical and Pharmaceutical Sciences
Osamu Ikeda, Hisashi Sakaguchi1), Michio Kawasuji1), Yasuyuki Yamashita
Department of Cardiovascular Surgery, Saiseikai Kumamoto Hospital
Ichiroh Ideta

 Purpose : We reported the successful treatment of solitary internal iliac artery aneurysms (IIAAs) by the placement of stent-grafts after embolization of distal branches of the internal iliac artery (IIA).
Materials and Methods : Four male patients (mean age, 77 years) with solitary IIAAs (mean diameter, 5.1b) underwent stent-grafting; of these, 3 received coil embolization of distal branches of the IIA to avoid aneurysm revascularization due to abundant pelvic collaterals. In the other patient, coil packing of the aneurysmal sac was necessary due to incomplete coil embolization of the distal branches of the IIA.
Results : Stent-graft placement was technically successful in 4 ; post procedure aortography obtained after treatment showed complete exclusion of the IIAAs. In one patients, stenosis at the stent joint was evident immediately after the procedure ; it was treated successfully by
balloon angioplasty. In all patients, CT obtained during the follow-up period (7~51 months) demonstrated complete thrombosis of the IAAs and patency of the stent-graft. There were no major complications such as buttock claudication, colonic mucosal ischemia, or iliac artery injury during or after the procedure.
Conclusion : Distal embolization of IIAAs followed by stent-graft placement is an effective alternative treatment in patients with IIAAs.

Key words
●Solitary internal iliac aneurysms
● Embolization

Original Articles
Feasibility Study on Medical Expenses in Percutaneous Vertebroplasty for Osteoporotic Compression Fractures
Department of Radiology, Kansai Medical University
Atsushi Komemushi, Noboru Tanigawa, Syuji Kariya, Hiroyuki Kojima
Yuzo Shomura, Yasuhiro Ueno, Satoshi Sawada
Medical Professions Division, Kansai Medical University Hospital
Miyoshi Miyata, Kiyohide Miyauchi

 Purpose : To evaluate the feasibility of percutaneous vertebroplasty for osteoporotic compression fractures based on medical expenses.
Patients and Method : The hospitalization-related medical expense of percutaneous vertebroplasty procedures for osteoporotic compression fractures was calculated using data from the national health insurance Fee For Service Reimbursement plan for procedures performed in our hospital between April 2004 and March 2005. Data from 32 patients, 37 hospitalizations and 37 percutaneous vertebroplasty procedures were included in this study.
Pre-procedural examinations included clinical laboratory examinations of blood, urine, and respiratory function ; electrocardiography ; and assessment of bone mineral density, bone scan, vertebral magnetic resonance imaging and chest and vertebral X-ray. Percutaneous vertebroplasty was performed under local anesthesia using the IVR-CT system, which combines angiographic and CT equipment with a single fluoroscopy table. Standard chest and vertebral radiographic examinations were conducted on the following day.
The cost of the percutaneous vertebroplasty procedure itself was assumed to be 94,800 yen.
Result : Mean length of stay was 8.97±2.69 days. Mean hospitalization-related medical expense was 390,552±7,904.6 yen. Mean daily hospitalization-related medical expense was 43,539 yen.
Conclusion : While percutaneous vertebroplasty reduces length of stay and hospitalization-related medical expenses, it increases daily hospitalization-related medical expenses.

Key words
●Percutaneous vertebroplasty
●Medical economics survey
●Clinical study
●Vertebral compression fracture

Case Report
Successful Treatment of a Duodenal Vvarix by Balloon-occluded Retrograde Transvenous Obliteration (BRTO) Combined with Proper Rotation of the Patient
Department of Radiology, Nagasaki University School of Medicine
Kenji Makino, Michiko Shindo, Ichiro Sakamoto, Masataka Uetani
Department of Radiology, Ureshino Medical Center
Ken-ichiro Fukui

A Man in his 40’s with portal hypertention due to alcoholic liver cirrhosis was referred to us for the treatment of upper gastrointestinal bleeding. Contrast-enhanced CT showed a duodenal varix draining through the tortuous retroperitoneal varices into the inferior vena cava. Endoscopic treatment was unfeasible since the patient had undergone gastrectomy with Billroth-II reconstruction. Hence, balloon occluded retrograde transvenous obliteration (BRTO) was attempted by the transfemoral approach. However, at the time of the BRTO procedure, retrograde insertion of a catheter from the inferior vena cava into the duodenal varix was unfeasible because of severe tortuosity of the retroperitoneal varices. Furthermore, contrast material injected in the retroperitoneal varices could not fill the duodenal varix. CT obtained during BRTO procedure revealed the duodenal varix to be located ventrally to the retroperitoneal varices. Contrast material, which was again injected with the patient rotated to the right posterior oblique position, could fill the duodenal varices sufficiently. Thereafter, 5% ethanolamin oleate with iopamidol (EOI) was subsequently injected in the right posterior oblique position, resulting in sufficient filling of EOI in the duodenal varix. Complete thrombosis of the duodenal varix was confirmed by CT obtained 3 days after the procedure. The duodenal varix did not recur during the follow-up period of 17 months.

Key words
● Varix

Case Report
Efficacy of Coil Embolization for Portohepatic Venous Shunts with Hepatic Encephalopathy
Department of Radiology, Kitasato University East Hospital
Mayumi Sasaki, Yoshinori Isobe
Department of Radiology, Sagamihara National Hospital
Masakazu Takigawa
Department of Radiology, Kitasato Laboratory Hospital
Hisashi Yanaihara
Department of Radiology, Kitasato University School of Medicine
Keiji Matsunaga, Hiroshi Nishimaki

 Portohepatic venous (PV) shunt is a relatively rare vascular malformation that causes hepatic encephalopathy. We performed coil embolization for 5 cases of PV shunts with uncontrollable hepatic encephalopathy. In 1 case with multiple PV shunts in bilateral lobes, transileocolic venous obliteration (TIO) was performed divided into three separate procedures because we were afraid of liver dysfunction by hepatic congestion. Serum ammonia level decreased after three sessions, and no complications or hepatic failure have occurred. However, the serum ammonia level rose again 6 years after the last TIO. Percutaneous transhepatic portal vein obliteration (PTO) was performed. Serum ammonia level had been controlled within normal levels for 5 years after PTO. PTO was performed in 3 cases with PV shunts in the liver. In 2 cases, transjugular venous obliteration (TVO) was performed first. However, some of the PV shunts could not be embolized ; therefore, PTO was performed to embolize them. Serum ammonia level decreased rapidly after the procedures in all cases, and no hepatic failure occurred from 1 to 9 years after the procedures. Embolization of a PV shunt is a safe and effective procedure for patients with hepatic encephalopathy.

Key words
●Portohepatic venous shunt
● Embolization

Case Report
Endovascular Stent Grafting after Total Arch Replacement for Type-A Acute Aortic Dissection Using a Elephant Trunk Technique : A Case Report
Department of Diagnostic Radiology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences
Osamu Ikeda, Yasuyuki Yamashita
Department of Radiology and Cardiovascular Surgery1), Saiseikai Kumamoto Hospital
Daisuke Utsunomiya, Taiji Nishiharu, Jhoji Urata
Ichiro Ideta1), Touitsu Hirayama1)

 Endovascular stent grafting after total arch replacement for type-A acute aortic dissection using a elephant trunk technique is reported in a woman in her 80’s. This case had a relapse of dissection in the descending aorta six years after the initial surgery. We repaired with endovascular stent grafting by inserting a stent graft in the elephant trunk. Endoleak developed in the follow-up, but it was repaired by additional stent grafting.

Key words
●Elephant trunk
●Stent grafting
● Aortic dissection

Case Report
Embolotherapy in a Case of Sacral Spinal Dural Arteriovenous Fistula
Departments of Radiology, Neurology1) and Neurosurgery2), Saga Medical School
Yoshiaki Egashira, Akira Uchino, Yukinori Takase, Yusuke Yakushiji1)
Kazuhiro Kurohara1), Takashi Hisatomi1), Toru Koizumi2), Sho Kudo

 We report an elderly man with a spinal dural arteriovenous fistula (AVF) in the sacral region fed by the right lateral sacral artery. The shunting point was the right second sacral level. The draining vein was an H-shaped epidural vein, and the dilated intradural coronal venous plexus was filled retrogradely.
Embolotherapy was successfully performed with n-butyl cyanoacrylate (n-BCA). After the procedure, the patient’s symptoms improved gradually. Transcatheter embolization with n-BCA for sacral spinal dural AVF is easy, safe, and effective.

Key words
●Sacral dural AVF
● n-BCA

Case Report
Seat Belt Breast Injury Treated by Transcatheter Arterial Embolization : A Case Report
Department of Radiology, Saga Medical School
Koichi Matsumoto, Sho Kudo
Department of Radiology, Emergency1), Saga Prefectural Hospital, KOHSEIKAN
Akihiro Inoue, Yukiko Tsuji, Tetsuro Kajiwara, Naohiro Fujita1)

 A woman in her 30’s wearing a three-point seat belt was involved in a motor vehicle accident while driving. Contrast-enhanced computed tomography (CT) of the chest showed a large breast hematoma with extravasation of contrast material. Although the patient’s vital signs remained stable, the hematoma gradually enlarged, and so we performed transcatheter arterial embolization (TAE). Angiography showed extravasation of contrast material from the second perforating branch of the left internal mammary artery, and TAE was performed successfully.
Breast injuries caused by seat belts have been previously reported, but few cases required any particular intervention. As shown in our case, active arterial extravasation of contrast material depicted by CT should be an indication for endovascular or surgical intervention.

Key words
●Breast injury
●Seat belt injury
●Transcatheter arterial embolization


杏林大学医学部 放射線科, 東京慈恵会医科大学 産婦人科1), 同 放射線科2), 久我山病院 産婦人科3)
岩元香保里, 舞床和洋1), 似鳥俊明, 田中忠夫1)
高橋修司, 貞岡俊一2), 中村幸雄3)

To investigate and quantify the clinical present status of uterine artery embolization (UAE) in Japan, a questionnaire relating to UAE was posted to members of Japan UAE Society and university hospitals. As a result, it becomes clear that 3230 UAE procedures were underwent in 118 hospitals of Japan so far, and that gelatine sponge particle was used as embolic materials in 97% facilities by this survey. Overall over 90% of symptom was improved without any fatal complication.

Key words
●Myoma uteri
●Uterin artery