IVR 会誌　Jpn J Intervent Radiol Vol.20 No.2 2005

State of the Art 1.　Principles of Radiation Protection in Fluoroscopically Guided Interventional Radiologic Procedures Department of Radiology, Aichi Medical University Tsuneo Ishiguchi, Seiji Kamei, Kazuko Ohno Abstract While interventional radiological procedures are minimally invasive and beneficial to patients, some complex and lengthy fluoroscopically guided procedures may cause radiation-induced skin injuries. Interventional radiologists should be aware of threshold doses, actual dose rates of a particular x-ray equipment, and proper techniques to control the patient’s cumulative skin dose. The International Commission on Radiation Protection recommends that informed consent be obtained about the risk of radiation injury, that the maximum dose to the skin be recorded when it approaches 1 Gy (for procedures that may be repeated) or 3 Gy (for any procedure) and that patient follow-up be provided in the latter situation. To reduce operator exposure, it is essential to avoid direct exposure of the primary beam to the hands in procedures such as transhepatic biliary drainage. During vascular interventions, the majority of operator exposure is caused by scatter radiation from the patient. Almost every effort to reduce patient dose secondarily reduces scatter radiation to the operator as well. The overhead x-ray tube system is associated with higher exposure to the hands and eyes, and should not be used for complicated procedures. Appropriate shields help in reducing scatter to the operator. Key words ● Fluoroscopy ● Interventional radiology ● Radiation injury

2.　Basic Knowledge of Radiation Exposure in CT-guided IVR Department of Radiology, Fujita Health University School of Medicine1) Faculty of Radiological Technology, Fujita Health University School of Health Sciences2) Ryoichi Kato, Tatsuo Banno, Kazuhiro Katada1), Shoichi Suzuki, Hirofumi Anno2) Abstract This article discussed the exposure dose to the patient and the operator in CT-guided IVR, and radiological protection. The CT dose index (CTDI) has commonly been used as the most specific dose quantity for CT examinations because it includes all relevant scan parameters: kV, tube current, slice thickness, pitch factor, and others. The exposure dose exceeded the diagnostic reference value in an abdominal high-resolution CT examination using 64-DAS MSCT. We also discussed the exposure dose to the patient during CT fluoroscopy. Because the X-ray beams used in CT fluoroscopy are narrow and the dose rate is low, radiation damage does not occur in usual use. One of the major limitations of CT fluoroscopy is excessive radiation exposure to the operator, in particular, to his or her hands. Therefore, we previously developed biopsy needle holders that permit the operator to manipulate the needle without placing his or her hands in the direct X-ray. We previously investigated the use of needle holders and protective goggles and aprons to reduce the exposure dose, and confirmed their effectiveness. These protective devices are considered to be indispensable in performing non-vascular interventional procedures under CT-fluoroscopic guidance. It had been confirmed that the occupational radiation doses in CT fluoroscopy do not exceed the limit specified by the ICRP when adequate protective devices are applied. Key words ● CTDI ● CT fluoroscopy ● Radiological protection

3.　Patient and Physician Doses during Interventional Procedures Department of Radiology, Teikyo University School of Medicine Shigeru Suzuki, Shigeru Furui, Hiroshi Kohtake Abstract Interventional radiology (IVR) procedures have recently spread quickly and achieved success with low invasiveness in the treatment of various diseases. However, radiation skin injuries in patients have been reported with the spread of IVR. The International Commission on Radiological Protection recommended to record an identification of those areas of the patient’s skin that received an absorbed dose during IVR procedures that may approach or exceed 1 Gy (for procedures that may be repeated) ; 3 Gy (for any procedure). We reviewed patient and interventional physician doses during interventional procedures based on previous reports and our experience. Patient’s exposure in IVR is affected by fluoroscopy time, number of acquisitions, beam angle, dose rate, and patient size. The interventional physician should understand generally the standard skin dose of the IVR procedure, the dose rate of the X-ray apparatus to be used, and the dose per DSA, etc. The high occupational exposures in IVR require adequate monitoring for staff. It is important for interventional physicians to estimate patient and staff radiation doses in individual procedures and make efforts to reduce the exposure doses. Key words ● Interventional Radiology ● Exposure dose ● Radiation injury

Original Article Effectiveness of prophylactic transcatheter arterial embolization for unruptured renal angiomyolipomas Department of Radiology and Urology1), Kumamoto Red Cross Hospital 　Takeshi Sugawara, Ryuichi Saito, Ryuji Murakami, Shinichi Takano1) 　Naohisa Mizukami, Yumi Yanaga Department of Radiological Sciences, School of Health Sciences, Kumamoto University School of Medicine 　Hirotada Butsuzaka Department of Radiology, Amakusa Medical Center 　Yoshinori Shigematsu, Yutaka Nakasone Department of Urology, Kumamoto Rosai Hospital 　Junzo Kudo Abstract Six patients with unruptured renal angiomyolipomas (AML) 4b or larger are presented, two of whom had tuberous sclerosis. In all patients, transcatheter arterial embolization (TAE) was performed in an attempt to prevent future life-threatening rupture. Renal angiograms showed that tumor vessels were not tortuous and a few in number, and superselective TAE could be achieved successfully. Post-TAE angiograms showed devascularization of the tumor. There were no serious complications and follow-up period of five to 180 months (mean, 54 months) revealed no bleeding. We consider that prophylactic superselective TAE for unruptured renal AML may be feasible and effective in the prevention of future bleeding. Key words ●Angiomyolipoma (AML) ●Transcatheter arterial embolization ●Prophylactic

Case Report Transcatheter Arterial Embolization of Pseudoaneurysm of the Profunda Femoris Artery after Total Hip Arthroplasty : A Case Report Department of Radiology, Fukuyama Medical Center, National Hospital Organization 　Hiroe Morita, Yoshihiro Kono, Norihisa Katayama, Tomio Nakagawa Department of Radiology, Graduate School of Medicine and Dentistry, Okayama University 　Susumu Kanazawa Abstract Pseudoaneurysm of the profunda femoris artery is rare, but is known as one of the vascular injuries occurring after orthopedic operations of the upper thigh. We report a case of pseudoaneurysm of the profunda femoris artery after total hip arthroplasty, which was successfully treated by transcatheter arterial embolization (TAE). A 79-year-old woman with a mass in the left thigh had undergone a total hip arthroplasty. Since anemia and thigh swelling developed after the surgery, the existence of pseudoaneurysm was suspected. We performed angiography, which showed a huge pseudoaneurysm of the left profunda femoris artery. We performed TAE using multiple metallic coils. At 6 months after TAE, dynamic CT scans revealed no recurrence of the pseudoaneurysm or hematoma. Key words ●Pseudoaneurysm ●Profunda femoris artery ●Transcatheter arterial embolization(TAE)

Case Report A Case of Emphysematous Cystitis Presenting Severe Hematuria ; Successful Treatment by Transcatheter Arterial Embolization Department of Radiology, Department of Urology1), Nakatsu Municipal Hospital 　Daisuke Tsurumaru, Hiromu Hidaka, Naohito Iwabuchi1) Department of Radiology, Matsuyama Red Cross Hospital 　Hiroyuki Nomiyama Abstract We experienced a case of emphysematous cystitis presenting severe hematuria. A 75-year-old woman was taken to our hospital with gross hematuria. Abdominal X-ray and CT showed intramural gas of the urinary bladder, which suggested the diagnosis of emphysematous cystitis. The patient presented severe hematuria and hypotension on the 27th hospital day. Pelvic angiography revealed extravasation from the left superior vesical artery. A microcatheter was advanced into the artery and transcatheter arterial embolization (TAE) using gelatin sponge particles was performed. Hemostasis was obtained, but rebleeding occurred 20 days later. Pelvic angiography revealed extravasation from another branch of the left superior vesical artery. TAE of the bilateral internal iliac artery using gelatin sponge particles was performed. Thereafter no bleeding occurred and the patient was discharged. TAE was a useful treatment for severe hematuria caused by emphysematous cystitis. Key words ●Emphysematous cystitis ●Transcatheter Arterial Embolization ●Hematuria

Technical Note A Newly Designed Nursing Manual for Interventional Radiology Department of Nursing and Radiology1), Nara Prefectural Nara Hospital Meiko Kitamura, Megumi Kusumoto, Naomi Sakamoto, Motoko Matsushita, Yumi Takagi, Etsumi Hagihara, Yoshie Fujii, Takeshi Wada1), Tetsuya Yoshioka1) Abstract It is our object to edit and supply a newly designed nursing manual for interventional radiology(IVR) to be used at clinical training. This manual is being redesigned to increase the quality of support and to improve the level of care between nursing and assisting doctors during the IVR procedure. This manual provides a Gantt chart. The horizontal axis shows step-by-step instructions for both nursing and assisting doctors during the medical procedure. The vertical axis shows time the passage of for the patient from his first entering the angiography suite to leaving the angiography suite. The use of this manual will allow nurses to effectively and efficiently perform their duties regardless of their past experience or level of training. This manual will also shorten their training period by providing hands-on experience, thus increasing their learning curve. It has been demonstrated that this manual will increase the quality and level of care for IVR patients and will be especially useful in those institutions with no designated IVR nursing staff. Key words ●Nursing ●Interventional Radiology ●Manual

Technical Note Experimental Investigation of Pluronic F-127 for Clinical Application Department of Radiology, Shiga University 　Norihisa Nitta, Shinichi Ota, Toyohiko Tanaka, Ryutaro Takazakura 　Michio Yamasaki, Masaru Sakota, Naoaki Kono, Akira Furukawa 　Masashi Takahashi, Kiyoshi Murata Department of Radiology, Kohka Public Hospital 　Katsuji Imoto, Tsutomu Sakamoto Abstract Pluronic (polyoxyethylene-polyoxypropylene) is a substance in widespread use in the medical and pharmaceutical fields. Most notably, Pluronic F127 has the properties of being liquid at 20 degrees centigrade or lower, and gelatinous from 20 to 40 degrees centigrade, where the gelatification temperature depends upon concentration. Taking advantage of this substance’s property-changing characteristic of gelatification at body temperatures, we have performed an experimental investigation regarding its properties including conductivity of radiofrequency (at 500 kHz) and absorbability following subcutaneous infusion. Its potential has also been explored for its use as a spacer (for securing routes for biopsy or in radio frequency ablation(RFA)), an embolic material, and a submucosal injection substance for endoscopic mucosal resection. Pluronic F127 was found to be potentially useful in various interventional radiology applications. Key words ●Pluronic F-127 ●Gelation and gel melting ●Embolic material

このページの先頭へ戻る