Springer Science and Business Media LLCActa Medica Okayama1341-96253082025Percutaneous cryoablation versus robot-assisted partial nephrectomy for small renal cell carcinoma: a retrospective cost analysis at Japanese single-institution16211630ENMayuUkaDepartment of Radiology, Okayama University HospitalToshihiroIguchiDepartment of Radiology, Okayama University HospitalKensukeBekkuDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesTomoakiYamanoiDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesToshiharuMitsuhashiCenter for Innovative Clinical Medicine, Okayama University HospitalHideoGobaraDivision of Medical Informatics, Okayama University HospitalNoriyukiUmakoshiDepartment of Radiology, Okayama University HospitalTakahiroKawabataDepartment of Radiology, Okayama University HospitalKojiTomitaDepartment of Radiology, Okayama University HospitalYusukeMatsuiDepartment of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityMotooArakiDepartment of Urology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesTakaoHirakiDepartment of Radiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama UniversityBackground: No direct cost comparison has been conducted between percutaneous cryoablation (PCA) and robot-assisted partial nephrectomy (RAPN) for clinical T1a renal cell carcinoma (RCC) in Japan. This study aimed to compare their costs.<br>
Methods: We retrospectively analyzed data from 212 PCAs (including 155 with transcatheter arterial embolization) and 119 RAPN cases performed between December 2017 and May 2022.<br>
Results: PCA patients were older with higher American Society of Anesthesiologists scores, Charlson Comorbidity Index, and history of previous RCC treatment, cardiovascular disease, and antithrombotic drug use than RAPN patients. PCA was associated with a significantly shorter procedure time and hospitalization duration with fewer major complications than those associated with RAPN. While PCA incurred a slightly lower total cost (1,123,000 vs. 1,155,000 yen), it had a significantly higher procedural cost (739,000 vs. 693,000 yen) and markedly worse total (− 93,000 vs. 249,000 yen) and procedural income-expenditure balance (− 189,000 vs. 231,000 yen) than those of RAPN. After statistical adjustment, PCA demonstrated significantly higher total (difference: 114,000 yen) and procedural costs (difference: 72,000 yen), alongside significantly worse total (difference: − 358,000 yen) and procedural income-expenditure balances (difference: − 439,000 yen). The incremental cost-effectiveness ratio was more favorable for PCA than for RAPN.<br>
Conclusion: For high- risk patients, PCA demonstrated a safer option with shorter hospitalization duration than those of RAPN. Although PCA was more cost-effective, its higher procedural cost and unfavorable income-expenditure balance require careful evaluation, especially for large tumors that require three or more needles.No potential conflict of interest relevant to this article was reported.Springer Science and Business Media LLCActa Medica Okayama1867-107140112022Percutaneous cryoablation for clinical T3a renal cell carcinoma (< 7 cm) with segmental vein involvement or perinephric fat invasion based on preoperative evaluation of high-resolution multidetector computed tomography scan12011209ENMayuUkaDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineToshihiroIguchiDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineNanakoOkawaDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineYusukeMatsuiDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineKojiTomitaDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineNoriyukiUmakoshiDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineKazuakiMunetomoDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineHideoGobaraDivision of Medical Informatics, Okayama University HospitalMotooArakiDepartment of Urology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicineTakaoHirakiDepartment of Radiology, Dentistry and Pharmaceutical Science, Okayama University Graduate School of MedicinePurpose To retrospectively assess the feasibility, safety, renal function, technique efficacy rate, and survival of patients with clinical T3a renal cell carcinoma (RCC).<br>
Materials and methods Sixteen cryoablation sessions were performed in 14 patients (10 men; mean age, 69.8 ± 10.5 years; range, 49–90 years) with 14 clear cell T3a RCCs (mean, 3.3 ± 0.9 cm; range, 1.9–5.2 cm). One patient was on dialysis. Transcatheter arterial embolization was performed before cryoablation in 15 sessions. The primary endpoint was the technique efficacy rate. The secondary endpoints included feasibility, safety, renal function, and survival.<br>
Results Cryoablation was technically successful in all RCC cases. In two RCCs, cryoablation was performed twice because of local tumor progression. No major adverse events were observed. All patients were alive without metastases, with a median follow-up of 45 months (6−93 months). Complete response was achieved by cryoablation in 11 RCCs (78.6%). The primary and secondary technique efficacy rates were 77.1% and 84.4% at 1 year, 57.9% and 73.9% at 3 years, and 57.9% and 73.9% at 5 years, respectively. One patient underwent dialysis given a total contralateral nephrectomy due to another RCC 1 month after initial cryoablation and a total ipsilateral nephrectomy 46 months after initial cryoablation due to local progression. Except for two dialysis patients, of the 12 patients with a median follow-up of 41 months (6–93 months), none were on dialysis.<br>
Conclusion Cryoablation was safe and effective in T3a RCC, which mainly involved the renal venous branches and may represent an alternative treatment for inoperable patients.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7512021Needle Tract Ablation in Liver Tissue Using a Cryoprobe Combined with an Electrosurgical Device: Influence of ex vivo and in vivo Animal Models914ENHideoGobaraDivision of Medical Informatics, Okayama University HospitalAkiraYamamotoDepartment of Diagnostic and Interventional Radiology, Osaka City University Graduate School of MedicineToshiyukiKomakicDepartment of Radiology, Okayama University HospitalToshiakiKitayamaDepartment of Radiology, Otemae HospitalJunSakuraiCenter for Innovative Clinical Medicine, Okayama University HospitalToshihiroIguchiDepartment of Radiology, Okayama University HospitalYusukeMatsuiDepartment of Radiology, Okayama University HospitalMayuUkaDepartment of Radiology, Okayama University HospitalKojiTomitaDepartment of Radiology, Okayama University HospitalTakaoHirakiDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSusumuKanazawaDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOriginal Article10.18926/AMO/61428To assess the feasibility of needle tract ablation in liver tissue in ex vivo and in vivo animal models using a cryo-probe and electrosurgical device. The experimental device is made by inserting a cryoprobe through an intro-ducer sheath for insulation, with 2-cm of probe tip projecting out. A beagle liver was punctured by the device, and electric current was applied at 30-W with the electrosurgical knife touching the non-insulated device base. The discolored area of cut surface along the device was evaluated in 5 application-time groups (5 , 10 , 15 , 20, or 25 seconds). An ex vivo experiment was performed to determine an ablation algorithm with an appropriate application time by comparison with radiofrequency ablation (RFA) results. Thereafter, an in vivo experiment was performed to verify the algorithm’s feasibility. In the ex vivo model, the cut surface demonstrated different amounts of discolored area according to the application time. The total discolored area in the 20-seconds group was similar to that by RFA. In the in vivo model, the liver did not bleed, the total discolored area was similar to that ex vivo, and coagulation necrosis was confirmed by photomicrograph. Needle tract ablation can be per-formed using the experimental device and electrosurgical device.No potential conflict of interest relevant to this article was reported.SpringerActa Medica Okayama0938-79943032019Robotic CT-guided out-of-plane needle insertion: comparison of angle accuracy with manual insertion in phantom and measurement of distance accuracy in animals13421349ENToshiyukiKomakiDepartment of Radiology, Okayama University Medical SchoolTakaoHirakiDepartment of Radiology, Okayama University Medical SchoolTetsushiKamegawaGraduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama UniversityTakayukiMatsunoGraduate School of Natural Science and Technology, Okayama UniversityJunSakuraiCenter for Innovative Clinical Medicine, Okayama University HospitalRyutaroMatsuuraGraduate School of Health Sciences, Okayama University Medical SchoolTakuyaYamaguchiDivision of Radiology, Department of Medical Technology, Okayama University HospitalTakanoriSasakiCollaborative Research Center for OMIC, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical SciencesToshiharuMitsuhashiCenter for Innovative Clinical Medicine, Okayama University HospitalSoichiroOkamotoDepartment of Radiology, Okayama University Medical SchoolMayuUkaDepartment of Radiology, Okayama University Medical SchoolYusukeMatsuiDepartment of Radiology, Okayama University Medical SchoolToshihiroIguchiDepartment of Radiology, Okayama University Medical SchoolHideoGobaraDivision of Medical Informatics, Okayama University HospitalSusumuKanazawaDepartment of Radiology, Okayama University Medical SchoolObjectives</br>
To evaluate the accuracy of robotic CT-guided out-of-plane needle insertion in phantom and animal experiments.</br>
Methods</br>
A robotic system (Zerobot), developed at our institution, was used for needle insertion. In the phantom experiment, 12 robotic needle insertions into a phantom at various angles in the XY and YZ planes were performed, and the same insertions were manually performed freehand, as well as guided by a smartphone application (SmartPuncture). Angle errors were compared between the robotic and smartphone-guided manual insertions using Student’s t test. In the animal experiment, 6 robotic out-of-plane needle insertions toward targets of 1.0 mm in diameter placed in the kidneys and hip muscles of swine were performed, each with and without adjustment of needle orientation based on reconstructed CT images during insertion. Distance accuracy was calculated as the distance between the needle tip and the target center.</br>
Results</br>
In the phantom experiment, the mean angle errors of the robotic, freehand manual, and smartphone-guided manual insertions were 0.4°, 7.0°, and 3.7° in the XY plane and 0.6°, 6.3°, and 0.6° in the YZ plane, respectively. Robotic insertions in the XY plane were significantly (p < 0.001) more accurate than smartphone-guided insertions. In the animal experiment, the overall mean distance accuracy of robotic insertions with and without adjustment of needle orientation was 2.5 mm and 5.0 mm, respectively.</br>
Conclusion</br>
Robotic CT-guided out-of-plane needle insertions were more accurate than smartphone-guided manual insertions in the phantom and were also accurate in the in vivo procedure, particularly with adjustment during insertion.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7062016Acute Bowel Injury due to Cryoablation for Renal Cell Carcinoma: Correlated Radiologic and Pathologic Findings511514ENHideoGobaraDepartment of Radiology,Okayama University HospitalTakaoHirakiDepartment of Radiology,Okayama University HospitalToshihiroIguchiDepartment of Radiology,Okayama University HospitalHiroyasuFujiwaraDepartment of Radiology,Okayama University HospitalTakeshiNagasakaDepartment of Gastroenterological Surgery, Okayama University HospitalHiroyukiKishimotoDepartment of Gastroenterological Surgery, Okayama University HospitalTakehiroTanakaDepartment of Pathology, Okayama University HospitalSusumuKanazawaDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical ScienceCase Report10.18926/AMO/54817An 87-year-old Japanese man underwent percutaneous cryoablation (PCA) therapy for his renal cell tumor. We displaced the colon from the tumor using hydrodissection. Computed tomography (CT) immediately after PCA was indicative of iceball extension to the colon wall, and a discontinuous enhancement of the colon wall was observed. We therefore performed an emergency surgery. On laparotomy, we observed a dark-purple area on the affected area of the colon, and the resected specimen showed focal, deep ulceration on the mucosal surface. Photomicrography revealed mucosal necrosis, submucosal hemorrhage, and necrotic foci in the muscularis propria, corresponding to the discontinuous colon wall enhancement on CT and the deep ulceration and dark-purple area on laparotomy. He recovered from surgery and was discharged without any complications.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7042016Single Center Prospective Phase II Trial of CT-guided Radiofrequency Ablation for Pulmonary Metastases from Colorectal Cancer (SCIRO-1401)317321ENJunSakuraiCenter for Innovative Clinical Medicine, Okayama University HospitalYusukeMatsuiDepartment of Radiology, Okayama University HospitalTakaoHirakiDepartment of Radiology, Okayama University HospitalToshihiroIguchiDepartment of Radiology, Okayama University HospitalHiroyasuFujiwaraDepartment of Radiology, Okayama University HospitalHideoGobaraDepartment of Radiology, Okayama University HospitalToshiharuMitsuhashiCenter for Innovative Clinical Medicine, Okayama University HospitalTakeshiNagasakaDepartment of Gastroenterological Surgery Transplant and Surgical Oncology, Okayama University HospitalSusumu KanazawaSusumu KanazawaDepartment of Radiology, Okayama University HospitalClinical Study Protocols10.18926/AMO/54512The present single center prospective phase II clinical trial is designed to evaluate the efficacy and safety of percutaneous radiofrequency (RF) ablation for colorectal lung metastases. Patients who have colorectal lung metastases without extrapulmonary metastases are included in this study. The primary endpoint is 3-year overall survival (OS) after RF ablation. The secondary endpoints are the prevalence of adverse events within 4 weeks, local tumor progression rate, 1- and 5-year OS, cause-specific survival, and relapse-free survival. The recruitment of patients commenced in July 2014, and the enrolment of 45 patients is intended over the 3 years of study period.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7042016Safety of Percutaneous Cryoablation in Patients with Painful Bone and Soft Tissue Tumors: A Single Center Prospective Study (SCIRO-1502)303306ENToshihiroIguchiDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesJunSakuraiCenter for Innovative Clinical Medicine, Okayama University HospitalTakaoHirakiDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHideoGobaraDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHiroyasuFujiwaraDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYusukeMatsuiDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesYoshihisaMasaokaDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSusumuKanazawaDepartment of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesClinical Study Protocols10.18926/AMO/54509This single center prospective study is being conducted to evaluate the safety of the cryoablation for patients with pathologically diagnosed painful bone and soft tissue tumors. Enrollment of 10 patients is planned over the 3-year recruitment period. Patients have related local pain after receiving medications or external radiation therapies will be included in this study. Cryoablation will be percutaneously performed under imaging guidance, and a temperature sensor will be used during treatment as necessary. The primary endpoint is prevalence of severe adverse events within 4 weeks after therapy. The secondary endpoint is effectiveness 4 weeks after the procedure.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X7042016A Case of Focal Bone Marrow Reconversion Mimicking Bone Metastasis: The Value of 111Indium Chloride285289ENTakashiTanakaDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHideoGobaraDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesRyotaInaiDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesToshihiroIguchiDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesAkihiroTadaDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesShuheiSatoDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesHiroyukiYanaiDepartment of Pathology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesSusumuKanazawaDepartment of Radiology , Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesCase Report10.18926/AMO/54505We present a case of a 66-year-old man with esophageal carcinoma. 18Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for evaluating distant metastasis and staging revealed 18F-FDG uptake in the third lumbar vertebra and other vertebrae. Magnetic resonance imaging could not differentiate bone metastases from benign bone lesions. We considered the possibility of bone marrow reconversion. 111Indium chloride (111In-Cl3) scintigraphy with single-photon emission computed tomography/computed tomography (SPECT/CT) revealed erythroid bone marrow components in the bone lesions. The diagnosis of bone marrow reconversion was pathologically confirmed by a bone biopsy of the third lumbar vertebra. The patient underwent esophagectomy and has remained disease-free in the 2 years since. To the best of our knowledge, this is the first report to describe the usefulness of 111In-Cl3 with SPECT/CT for the diagnosis of bone marrow reconversion.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6722013Management of Lumbar Artery Injury Related to Pedicle Screw Insertion113116ENYoshihisaSugimotoMasatoTanakaHideoGobaraHaruoMisawaToshiyukiKunisadaToshifumiOzakiCase Report10.18926/AMO/49670We report on 2 patients who experienced injury to one of their lumbar arteries related to pedicle screw misplacement. In this report, the lumbar pedicle screw holes were made laterally with resultant injury to the lumbar artery. During surgery, arterial bleeding was controlled with pressure and gauze;
however, the patients experienced vital shock after surgery. Vital shock ensued and they were rescued by catheter embolization. If patients receiving lumbar instrumentation surgery experience severe anemia or vital shock postoperatively, the surgeon should assume lumbar artery injury as a differential diagnosis.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6722013The Maximum Standardized Uptake Value Is More Reliable Than Size Measurement in Early Follow-up to Evaluate Potential Pulmonary Malignancies Following Radiofrequency Ablation105112ENAierkenAlafateTakayoshiShinyaYoshihiroOkumuraShuheiSatoTakaoHirakiHiroakiIshiiHideoGobaraKatsuyaKatoToshiyoshiFujiwaraShinichiroMiyoshiMitsumasaKajiSusumuKanazawaOriginal Article10.18926/AMO/49669We retrospectively evaluated the accumulation of fluorodeoxy glucose (FDG) in pulmonary malignancies without local recurrence during 2-year follow-up on positron emission tomography (PET)/computed tomography (CT) after radiofrequency ablation (RFA). Thirty tumors in 25 patients were studied (10 non-small cell lung cancers;20 pulmonary metastatic tumors). PET/CT was performed before RFA, 3 months after RFA, and 6 months after RFA. We assessed the FDG accumulation with the maximum standardized uptake value (SUVmax) compared with the diameters of the lesions. The SUVmax had a decreasing tendency in the first 6 months and, at 6 months post-ablation, FDG accumulation was less affected by inflammatory changes than at 3 months post-RFA. The diameter of the ablated lesion exceeded that of the initial tumor at 3 months post-RFA and shrank to pre-ablation dimensions by 6 months post-RFA. SUVmax was more reliable than the size measurements by CT in the first 6 months after RFA, and PET/CT at 6 months post-RFA may be more appropriate for the assessment of FDG accumulation than that at 3 months post-RFA.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6562011The Usefulness of Pre-Radiofrequency Ablation SUVmax in 18F-FDG PET/CT to Predict the Risk of a Local Recurrence of Malignant Lung Tumors after Lung Radiofrequency Ablation395402ENSosukeHaradaShuheiSatoEtsujiSuzukiYoshihiroOkumuraTakaoHirakiHideoGobaraHidefumiMimuraSusumuKanazawaMitsumasaKajiToshiyoshiFujiwaraOriginal Article10.18926/AMO/47265The aim of the present study was to assess the diagnostic usefulness of Fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the prediction of local recurrence of malignant lung tumors by analyzing the pre-radiofrequency ablation (RFA) maximal standardized uptake value (SUVmax). We performed a historical cohort study of consecutive malignant lung tumors treated by RFA from January 2007 to May 2008 at Okayama University Hospital. We selected only lung tumors examined by PET/CT within 90 days before RFA and divided them (10 primary and 29 metastatic) into 3 groups according to their tertiles of SUVmax. We calculated recurrence odds ratios in the medium group and the high group compared to the low group using multivariate logistic analysis. After we examined the relationship between SUVmax and recurrence in a crude model, we adjusted for some factors. Tumors with higher SUVmax showed higher recurrence odds ratios (medium group;1.84, high group;4.14, respectively). The tumor size also increased the recurrence odds ratio (2.67);we thought this was mainly due to selection bias because we excluded tumors less than 10mm in diameter. This study demonstrated the pre-RFA SUVmax in PET/CT may be a prognostic factor for local recurrence of malignant lung tumors.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6552011A Case of Renal Transcatheter Arterial Embolization with Ethanol in Autosomal Dominant Polycystic Kidney Disease for Volume Reduction347351ENTakashiMukaiHidefumiMimuraHideoGobaraMitsuharuShimizuHarutakaNiiyaSusumuKanazawaCase Report10.18926/AMO/47018We report herein the case of a 76-year-old woman with autosomal dominant polycystic kidney disease (ADPKD) and chronic renal failure resulting in intractable abdominal distension and anorexia. Computed tomography (CT) showed enlarged and cystic kidneys. We performed transcatheter arterial embolization (TAE) for renal arteries with ethanol. Absolute ethanol with iodinated contrast medium or Lipiodol was delivered into both renal arteries. The patient's low-grade fever subsided in 5 days, and no other complication occurred. The sensation of abdominal distension diminished approximately 1 month after embolization. A progressive decrease in kidney size was observed soon after embolization. The percentage of the decrement of kidney size was approximately 50% after 17 months. These results indicate that renal TAE with ethanol is a safe, cost-effective, and minimally invasive technique to reduce kidney size in symptomatic ADPKD patients.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6552011Radiofrequency Ablation of Lung Cancer at Okayama University Hospital: A Review of 10 Years of Experience287297ENTakaoHirakiHideoGobaraHidefumiMimuraShinichiToyookaHiroyasuFujiwaraKotaroYasuiYoshifumiSanoToshihiroIguchiJunSakuraiNobuhisaTajiriTakashiMukaiYusukeMatsuiSusumuKanazawaReview10.18926/AMO/47010The application of radiofrequency ablation for the treatment of lung cancer by our group at Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences began in June 2001, and in the present report, we review our 10-year experience with this treatment modality at Okayama University Hospital. The local efficacy of radiofrequency ablation for the treatment of lung cancer depends on tumor size and the type of electrode used, but not on tumor type. An important factor for the prevention of local failure may be the acquisition of an adequate ablative margin. The combination of embolization and radiation therapy enhances the local efficacy. Local failure may be salvaged by repeating the radiofrequency ablation, particularly in small tumors. Survival rates after radiofrequency ablation are quite promising for patients with clinical stage I non-small cell lung cancer and pulmonary metastasis from colorectal cancer, hepatocellular carcinoma, and renal cell carcinoma. The complications caused by radiofrequency ablation can be treated conservatively in the majority of cases. However, attention should be paid to rare but serious complications. This review shows that radiofrequency ablation is a promising treatment for patients with lung cancer.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6132007Radiofrequency ablation followed by radiation therapy for large primary lung tumors177180ENTakashiMukaiHidefumiMimuraHideoGobaraMitsuhiroTakemotoKengoHimeiTakaoHirakiSoichiroHaseHiroyasuFujiwaraToshihiroIguchiNobuhisaTajiriJunSakuraiKotaroYasuiYoshifumiSanoHiroshiDateSusumuKanazawaCase Report10.18926/AMO/32906We report the clinical experience of radiofrequency ablation followed by radiation therapy for large primary lung tumors. Two patients with large primary lung tumors were treated with combined radiofrequency ablation and radiation therapy, and good local control was observed. Combined radiofrequency ablation and radiation therapy that involves minimally invasive techniques appears to be promising for the treatment of large lung tumors.No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6332009Infusion of Hypertonic Saline into the Lung Parenchyma during Radiofrequency Ablation of the Lungs with Multitined Expandable Electrodes:Results Using a Porcine Model137144ENTatsuhikoIishiTakaoHirakiHidefumiMimuraHideoGobaraTaichiKuroseHiroyasuFujiwaraJunSakuraiHiroyukiYanaiTadashiYoshinoSusumuKanazawaOriginal Article10.18926/AMO/31848<p>The present study was performed to clarify the effect of hypertonic saline infusion into the lung parenchyma on radiofrequency ablation (RFA) of the lungs. A total of 20 ablation zones were created in 3 pigs. The ablation zones were divided into 3 groups. Group 1 (n6) consisted of ablation zones created by applying smaller radiofrequency (RF) power without saline infusion;group 2 (n5) zones were created by applying greater RF power without saline infusion;and group 3 (n9) zones were created by applying greater RF power with saline infusion. The techniques of saline infusion included administration of hypertonic saline 1ml before RFA, followed by continuous administration at a rate of 1ml/min during the first 2min after the initiation of RFA. The ablation parameters and coagulation necrosis volumes were compared among the groups. Group 3 had a tendency toward smaller mean impedance than group 1 (p0.059) and group 2 (p0.053). Group 3 showed significantly longer RF application time than group 2 (p0.004) and significantly greater maximum RF power than group 1 (p0.001) and group 2 (p0.004). Group 3 showed significantly larger coagulation necrosis volume (mean, 1,421mm3) than group 2 (mean, 858mm3, p0.039) and had a tendency toward larger necrosis volume than group 1 (mean, 878mm3, p0.077). Although this small study had limited statistical power, hypertonic saline infusion during RFA appeared to enlarge coagulation necrosis of the lung parenchyma.</p>No potential conflict of interest relevant to this article was reported.Okayama University Medical SchoolActa Medica Okayama0386-300X6022006Effects of radiofrequency ablation on individual renal function: assessment by technetium-99m mercaptoacetyltriglycine renal scintigraphy.8591ENTakashiMukaiShuheiSatoToshihiroIguchiHidefumiMimuraKotaroYasuiHideoGobaraTakashiSaikaYasutomoNasuHiromiKumonSusumuKanazawaArticle10.18926/AMO/30731We quantitatively evaluated total and individual renal function by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renal scintigraphy before and after radiofrequency ablation (RFA) of renal tumors. Eleven patients who underwent Tc-99m MAG3 renal scintigraphy 1 week before and after RFA were evaluated (7 men and 4 women ; age range : 23-83 years ; mean age : 60.6 years). Five patients had solitary kidneys, and five had normally or minimally functioning contralateral kidneys. One patient had a renal cell carcinoma in the contralateral kidney. One patient with a solitary kidney underwent RFA a second time for a residual tumor. In patients with a solitary kidney, MAG3 clearance decreased after 5 of 6 RFAs, and in patients with a normally functioning contralateral kidney, MAG3 clearance decreased after 4 of 5 RFAs, but no significant differences were observed between before and after treatments. In addition to the total MAG3 clearance, the split MAG3 clearance was evaluated in patients with a normally functioning contralateral kidney. MAG3 clearance decreased in 4 of 5 treated kidneys, while it adversely increased in the contralateral kidneys after 4 of 5 RFAs. No significant differences, however, were observed between before and after treatments. The results of our study revealed no significant differences in sCr, BUN, CCr, or MAG3 clearance between pre- and post-RFA values. These results support data regarding the functional impact and safety of renal RFA in published reports. We evaluated total and individual renal function quantitatively using Tc-99m MAG3 renal scintigraphy before and after treatment. This scintigraphy was very useful in assessing the effects of RFA on renal function.No potential conflict of interest relevant to this article was reported.岡山医学会Acta Medica Okayama0030-155812212010血管腫・血管奇形に対するinterventional radiology5559ENHidefumiMimuraHiroyasuFujiwaraTakaoHirakiHideoGobaraKentaroShibamotoYoshihiroKimataToshifumiOzakiSatoruSasakiSusumuKanazawaNo potential conflict of interest relevant to this article was reported.岡山医学会Acta Medica Okayama0030-155811822006気管冷却下に施行した縦隔リンパ節転移に対するラジオ波焼灼療法105108ENNo potential conflict of interest relevant to this article was reported.Acta Medica Okayama1995Tc-GSAによるラット一時的肝静脈遮断モデルにおける肝細胞障害の定量的評価ENNo potential conflict of interest relevant to this article was reported.