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Yoshitaka Inaba,
Fumihiko Kanai,
Takeshi Aramaki,
Takanobu Yamamoto, Toshihiro Tanaka,
Koichiro Yamakado,
Shuichi Kaneko,
Masatoshi Kudo,
Kazuho Imanaka,
Shinichi Kora,
Norifumi Nishida,
Nobuyuki Kawai,
Hiroshi Seki,
Osamu Matsui,
Hitoshi Arioka,
Yasuaki Arai
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ABSTRACT: BACKGROUND: TSU-68 is an antitumour drug that acts by inhibiting angiogenesis. We evaluated the efficacy and safety of TSU-68 in combination with transarterial chemoembolisation (TACE) in patients with intermediate-stage hepatocellular carcinoma (HCC). PATIENTS AND METHODS: In this multicenter, open-label phase II study, we randomised patients with HCC who had been treated with a single session of TACE to receive either 200mg TSU-68 twice daily or no medication. The primary end-point was progression-free survival (PFS). RESULTS: A total of 103 patients were enrolled. Median PFS was 157.0days (95% confidence interval [CI], 124.0-230.0days) in the TSU-68 group and 122.0days (95% CI, 73.0-170.0days) in the control group. The hazard ratio was 0.699 (95% CI, 0.450-1.088). Fatigue, elevated aspartate aminotransferase (AST), elevated alkaline phosphatase, oedema and anorexia were more frequent in the TSU-68 group than in the control group. The most frequent grade 3/4 adverse events were AST elevation (46% of patients in the TSU-68 group and 12% of controls) and alanine aminotransferase elevation (26% of patients in the TSU-68 group and 8% of controls). Two deaths, grade 5 hepatic failure and melena were noted in the TSU-68 group. CONCLUSION: This exploratory study shows a trend towards prolonged PFS with TSU-68 treatment after a single session of TACE, but this observation was not statistically significant. The two deaths were related to the study treatment. These results suggest that further examination of the study design is necessary to determine whether TSU-68 has any clinical benefits when combined with TACE.
European journal of cancer (Oxford, England: 1990) 06/2013; · 4.12 Impact Factor
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ABSTRACT: OBJECTIVE: Contrast-enhanced computed tomography (CE-CT) has been commonly used for follow-up imaging after endovascular aneurysm repair (EVAR), but it is difficult to use on patients with renal insufficiency. Superparamagnetic iron oxide (SPIO) particles, contrast medium for magnetic resonance imaging (MRI) that has been widely used for detection of the liver tumor, rarely affects renal function. The present study examined SPIO-enhanced dynamic MRI as a potential alternative to CE-CT for detection of endoleaks after EVAR. METHODS: Institutional review board approval was obtained for this prospective study. Twenty-three consecutive patients with normal renal function were evaluated using both CE-CT and SPIO-enhanced MRI within 2 weeks after EVAR. The median interval between the two modalities was 2 days. SPIO-enhanced MRI was performed at 1.5 T with T1-weighted, SPIO-enhanced dynamic, and postcontrast T1-weighted gradient echo sequences. The CE-CT protocol consisted of triple scans. Two experienced, blinded observers evaluated all images. Consensus reading of CE-CT and SPIO-MRI was defined as the reference standard. Interobserver, intraobserver, and intermodality agreement for endoleak detection was assessed by κ statistics. RESULTS: A total of 11 type II endoleaks originating from either the lumbar or inferior mesenteric artery were detected. Eight were able to be detected by CE-CT (8/11:73%) and 10 (10/11:91%) by SPIO-enhanced MRI. Interobserver (κ = 0.91; 95% CI, 0.74-1.00) and intraobserver agreement for MRI (κ = 1.00) were excellent. Intermodality agreement for endoleak detection was moderate (κ = 0.63; 95% CI, 0.32-0.94; and κ = 0.62; 95% CI, 0.29-0.95 for observers A and B, respectively). CONCLUSIONS: SPIO-enhanced MRI could represent a useful alternative to CE-CT, as it offers excellent interobserver, intraobserver agreement, and could detect more endoleaks than CE-CT.
Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 04/2013; · 3.52 Impact Factor
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ABSTRACT: We report a case of a 50-year-old male with isolated pancreatic metastasis from hepatocellular carcinoma (HCC), in which chemical shift magnetic resonance imaging detected the presence of fat, and which mimicked fatty replacement. A solitary metastatic pancreatic tumor originating from HCC is very rare. Furthermore, we believe that this is the first report of fat-containing pancreatic metastasis from HCC.
Japanese journal of radiology 03/2013; · 0.65 Impact Factor
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American Journal of Roentgenology 02/2013; 200(2):468. · 2.78 Impact Factor
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ABSTRACT: Purpose. Interventional treatment strategies for patients with encephalopathy due to splenorenal shunt remain controversial. Portosplenic blood flow separation by occluding the splenic vein could avoid the complication of severe portal hypertension, but it would require repeated reintervention due to recurrence of symptoms. This paper describes occlusion of the splenic vein using coil anchors and prophylactic embolization of a collateral hepatofugal vessel with no recurrence of hyperammonemia. Materials and Methods. A 51-year-old woman with severe cirrhosis had hepatic encephalopathy due to a large splenorenal shunt. The serum ammonia level was 132 μ g/dL. Via a transileocolic approach, the splenic vein was completely embolized with 0.035-inch metallic coils using coil anchors while preserving the splenorenal shunt. In addition, one of the collateral vessels of the portal vein, the retrogastric vein, was also embolized prophylactically. Results. After this procedure, the serum ammonia level decreased immediately to 24 μ g/dL. The portal venous pressure increased by only 1.5 mmHg. Hepatic encephalopathy had not been observed for 25 months after the procedure, and neither retention of ascites nor worsening of esophageal varices and liver function was observed. Conclusion. This procedure appears to be safe and effective for hepatic encephalopathy caused by a splenorenal shunt.
Case reports in radiology. 01/2013; 2013:160653.
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Hideyuki Nishiofuku, Toshihiro Tanaka,
Masaki Matsuoka,
Toshio Otsuji,
Hiroshi Anai,
Satoru Sueyoshi,
Yoshitaka Inaba,
Fumikazu Koyama,
Masayuki Sho,
Yoshiyuki Nakajima,
Kimihiko Kichikawa
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ABSTRACT: PURPOSE: To report the results of a phase I/II study of a transcatheter arterial chemoembolization protocol using cisplatin powder and degradable starch microspheres (DSM) for unresectable colorectal liver metastases after failure of FOLFOX (5-flourouracil, leucovorin plus oxaliplatin) chemotherapy conducted to determine the recommended dose of cisplatin powder and to assess the efficacy and safety of the protocol. MATERIALS AND METHODS: A fine-powder formulation of cisplatin was mixed with DSM and administered via the hepatic artery every 4 weeks. In phase I, three cohorts of patients received escalating doses of cisplatin powder: 50 mg/m(2), 65 mg/m(2), and 80 mg/m(2). In phase II, tumor response, toxicity, and survival times were assessed. RESULTS: The study enrolled 24 patients. Previously, FOLFOX had been administered to all patients, an irinotecan-containing regimen had been administered to 12 patients, and bevacizumab or cetuximab or both had been administered to 14 patients. In phase I, dose-limiting toxicity did not appear at any level, and the recommended dose of cisplatin powder was determined to be 80 mg/m(2). In phase II, a tumor response rate of 61.1% was achieved. The median hepatic progression-free survival and overall survival were 8.8 months (95% confidence interval [CI], 4.06-13.5 mo) and 21.1 months (95% CI, 8.37-33.8 mo). The following grade 3 toxicities were observed: thrombocytopenia (12.5%), aspartate transaminase elevation (33.3%), alanine transaminase elevation (12.5%), hyponatremia (8.3%), and cholecystitis (4.2%). CONCLUSIONS: This study shows that transcatheter arterial chemoembolization with cisplatin powder at a dose of 80 mg/m(2) mixed with DSM is well tolerated and can produce a high response rate with a long survival time for patients with unresectable colorectal liver metastases after failure of FOLFOX.
Journal of vascular and interventional radiology: JVIR 11/2012; · 1.81 Impact Factor
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ABSTRACT: A 70-year-old man with liver cirrhosis due to hepatitis C viral infection had a single well-differentiated hepatocellular carcinoma(HCC) of 5-cm diameter in the right superior anterior segment of the liver. Surgery could not be performed because of his poor liver function. Furthermore, it was difficult to treat this tumor with transcatheter arterial chemoembolization because the tumor exhibited hypovascularity. Radiofrequency ablation (RFA) alone was also not an option because the tumor was too large to manage with a simple RFA procedure. This solitary tumor was adjacent to the right and middle hepatic veins. Finally, we planned to treat this tumor with RFA and temporary vessel occlusion as follows: RFA was performed with a 5-cm expandable type RITA model 90 electrode under temporary occlusions of the right anterior hepatic artery with degradable starch microspheres, and of the right and middle hepatic veins by balloon catheters, to reduce the heat sink effect and obtain a larger coagulation size. We successfully treated this HCC with RFA combined with temporary vessel occlusion, and the patient has not obtained local recurrence at 18 months of the procedure.
Gan to kagaku ryoho. Cancer & chemotherapy 11/2012; 39(12):1822-4.
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ABSTRACT: Objective: Miriplatin(MP) is a promising newly developed anticancer agent for transcatheter arterial chemoinfusion in patients with hepatocellular carcinoma(HCC), particularly those previously not treated with chemotherapy. The aim of this study was to assess the efficacy and safety of transarterial chemolipiodolization with MP for recurrent HCC in patients previously treated with chemotherapy. Materials and Methods: From January 2010 to March 2011, 17 patients with recurrent HCC were treated with MP via a transcatheter arterial approach. The dose of MP per treatment session was up to 140 mg. We repeated this treatment protocol until tumor progression occurred. We assessed the therapeutic results and the adverse events. Results: MP was infused at a dose of 60-140 mg in the initial treatment session; the mean treatment session number was 1.8; and the total dose of MP was 60-400 mg (median, 120 mg). Response rate and disease control rate after the initial treatment were 17.6% and 47.1%,respectively. Response rate and disease control rate after the total treatment session were 17.6% and 29.4%,respectively. Median tumor-free survival was 86 days. We encountered a severe adverse event in 1 patient who died due to his concomitant disease( diabetic nephropathy and radiation hepatitis) 38 days after this protocol. Conclusion: The therapeutic result of MP was unsatisfactory, but adverse events due to MP infusion, including renal and/or liver damage, were minor.
Gan to kagaku ryoho. Cancer & chemotherapy 11/2012; 39(12):1840-2.
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ABSTRACT: PURPOSE: To evaluate the effects of particle size and course of action of superselective bland transcatheter arterial embolization (TAE) on the efficacy of radiofrequency ablation (RFA). METHODS: Twenty pigs were divided into five groups: group 1a, 40-μm bland TAE before RFA; group 1b, 40-μm bland TAE after RFA; group 2a, 250-μm bland TAE before RFA; group 2b, 250-μm bland TAE after RFA and group 3, RFA alone. A total of 40 treatments were performed with a combined CT and angiography system. The sizes of the treated zones were measured from contrast-enhanced CTs on days 1 and 28. Animals were humanely killed, and the treated zones were examined pathologically. RESULTS: There were no complications during procedures and follow-up. The short-axis diameter of the ablation zone in group 1a (mean ± standard deviation, 3.19 ± 0.39 cm) was significantly larger than in group 1b (2.44 ± 0.52 cm; P = 0.021), group 2a (2.51 ± 0.32 cm; P = 0.048), group 2b (2.19 ± 0.44 cm; P = 0.02), and group 3 (1.91 ± 0.55 cm; P < 0.001). The greatest volume of ablation was achieved by performing embolization with 40-μm particles before RFA (group 1a; 20.97 ± 9.65 cm(3)). At histology, 40-μm microspheres were observed to occlude smaller and more distal arteries than 250-μm microspheres. CONCLUSION: Bland TAE is more effective before RFA than postablation embolization. The use of very small 40-μm microspheres enhances the efficacy of RFA more than the use of larger particles.
CardioVascular and Interventional Radiology 10/2012; · 2.09 Impact Factor
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ABSTRACT: Hepatic arterial infusion chemotherapy (HAIC) combined with sorafenib is considered to be a promising therapeutic strategy for patients with advanced hepatocellular carcinoma. However, this combination therapy carries the risk of hepatic arterial thrombosis (HAT), which interrupts the continuation of HAIC, due to the side-effects of sorafenib. This case demonstrates a complication of HAT which occurred during HAIC combined with sorafenib. HAT was detected early by angiography via an implantable port-catheter system and was successfully treated with catheter-directed thrombolysis.
Anticancer research 09/2012; 32(9):4121-4. · 1.73 Impact Factor
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Masayuki Sho,
Takahiro Akahori, Toshihiro Tanaka,
Shoichi Kinoshita,
Tetsuro Tamamoto,
Takeo Nomi,
Ichiro Yamato,
Daisuke Hokuto,
Satoshi Yasuda,
Chihiro Kawaguchi,
Hideyuki Nishiofuku,
Nagaaki Marugami,
Yasunori Enomonoto,
Takahiko Kasai,
Masatoshi Hasegawa,
Kimihiko Kichikawa,
Yoshiyuki Nakajima
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ABSTRACT: BACKGROUND/PURPOSE: The therapeutic options available as preoperative strategies for resectable pancreatic cancer have received worldwide attention. We have recently introduced neoadjuvant chemoradiotherapy (NACRT) to achieve local control and possibly complete cure. In this study, we have retrospectively evaluated its impact on pathology and the perioperative clinical course in addition to its safety. METHODS: Sixty-one patients who received full-dose gemcitabine (1000 mg/m(2)) preoperatively with concurrent radiation (50 or 54 Gy) were evaluated. Seventy-one patients who received no preoperative therapy served as controls. Perioperative outcomes, postoperative complications, immunonutritional status, and the performance of adjuvant chemotherapy were compared. RESULTS: Fifty-nine patients (97 %) completed NACRT. Toxicity was acceptable and the regimen was feasible as outpatient treatment. The perioperative outcomes were closely comparable to control. The rate of pancreatic fistula was lower and hospital stay was shorter in the NACRT group. The rate of lymph node metastasis and stage was lower in the NACRT group. Furthermore, R0 resection could be achieved in 92 % of patients treated with NACRT. Nutritional status decreased after NACRT and further deteriorated during adjuvant chemotherapy. The initiation of postoperative chemotherapy was delayed in the NACRT group. CONCLUSIONS: Our current protocol of neoadjuvant chemoradiotherapy is feasible and substantially improves the pathology. However, it has some detrimental effects on postoperative nutritional status and performance of adjuvant chemotherapy. Furthermore, it should be noted that there is a possibility of arterial complications.
Journal of hepato-biliary-pancreatic sciences. 07/2012;
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ABSTRACT: Response rates to systemic chemotherapy for unresectable pancreatic cancer are low. The purposes of this phases 1 and 2 study of intraarterial therapy were to ascertain the recommended dose of intraarterial chemoinfusion and to evaluate the efficacy and safety of this therapy.
Pancreatic arteries originating from the superior mesenteric artery (the anterior and posterior inferior pancreaticoduodenal and the dorsal pancreatic) were embolized to achieve a single blood supply from the celiac artery to manage pancreatic cancer, and a catheter-port system was placed. Intraarterial 5-fluorouracil (5-FU) and IV gemcitabine (fixed dose of 1000 mg/m(2)) were administered. In phase 1, doses of 5-FU were increased from 750 to 1000 mg/m(2). In phase 2, tumor response, toxicity, and survival time were assessed.
A total of 20 patients were enrolled. In 19 patients (95%), the technique to unify the pancreatic blood supply was successful. No severe toxicity was observed with escalation of the 5-FU dose. The tumor response rate was 68.8%. The median overall survival time was 9.8 months and the progression-free survival time, 6.0 months. The grade 3 toxicities neutropenia (15.8%) and thrombocytopenia (5.3%) occurred.
In intraarterial administration of 5-FU at a dose of 1000 mg/m(2) combined with full-dose systemic gemcitabine for unresectable pancreatic cancer, the toxicity rate was acceptable, and response rate and survival time improved over those for treatment with gemcitabine alone.
American Journal of Roentgenology 06/2012; 198(6):1445-52. · 2.78 Impact Factor
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ABSTRACT: The purpose of this study was to assess the safety of hepatic arterial infusion (HAI) chemotherapy after pancreatectomy for pancreatobiliary cancer.
The study subjects comprised 51 patients treated with HAI chemotherapy after pancreatectomy: 31 patients had undergone pancreaticoduodenectomy or total pancreatectomy and 20 patients had undergone distal pancreatectomy. HAI chemotherapy was performed for the prevention of liver metastasis in 42 patients and for the treatment of metastases in nine patients. HAI chemotherapy consisted of 5-fluorouracil administered at 1000 mg/m(2)/wk. After each cycle of chemotherapy, the patency of the hepatic artery and complications were evaluated using digital subtraction angiography and CT arteriography via the catheter-port system.
Placement of the catheter-port system was successful in all patients. Hepatic arterial occlusion and severe asymptomatic hepatic artery stenosis were observed in one patient (2%) and 10 patients (19.6%), respectively. The hepatic arterial patency rate tended to be lower in the group who underwent pancreaticoduodenectomy or total pancreatectomy (71%) than in the group who underwent distal pancreatectomy (90%), although the difference was not significant (p = 0.107). Four asymptomatic patients with hepatic artery stenosis restarted HAI chemotherapy after a 4-week withdrawal of treatment. In three patients (5.9%), all of whom had undergone pancreaticoduodenectomy, liver abscess or biloma developed synchronously with asymptomatic hepatic artery stenosis. All three cases were cured by percutaneous abscess drainage or conservative management. The tumor response rate in the treatment of liver metastases was 44.4%. The hepatic recurrence rate with adjuvant therapy was 7.1%.
Our findings suggest that HAI chemotherapy after pancreatectomy is feasible and tolerable, although caution is required particularly after pancreaticoduodenectomy or after total pancreatectomy.
American Journal of Roentgenology 04/2012; 198(4):923-30. · 2.78 Impact Factor
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ABSTRACT: Although chemoradiotherapy with full-dose gemcitabine as a strategy for locally advanced pancreatic cancer was expected to optimize local tumor control and prevent distant metastasis, the volume of the radiation field is the critical factor related to toxicities. We are currently developing a novel therapeutic technique to conduct neoadjuvant treatments of intra-arterial chemoinfusion prior to chemoradiotherapy with the aim of tumor volume reduction. Case
In two patients with locally invasive pancreatic cancer, the pancreatic blood supply was altered under angiographic guidance, and an intra-arterial catheter with a subcutaneous port was left in place for the administration of 5-fluorouracil (5-FU) 1,000 mg/m(2). After shrinkage of the tumor, chemoradiotherapy with gemcitabine 1,000 mg/m(2) was delivered. In both patients, the full-dose gemcitabine was administered concurrently with radiation therapy without severe complications. The patients responded to the treatment with survival times of 42 and 38 months.
Intra-arterial chemoinfusion followed by chemoradiation with full-dose systemic gemcitabine might prove to be a promising therapeutic approach for locally advanced pancreatic cancer. Large prospective Phase II trials of this combination regimen are warranted.
Anticancer research 11/2011; 31(11):3909-12. · 1.73 Impact Factor
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ABSTRACT: To evaluate the feasibility of computed tomography (CT)-guided placement of inferior vena cava (IVC) filters in a swine model.
Five domestic pigs (60-70 kg) underwent transfemoral and transjugular IVC filter placement under real-time CT fluoroscopic guidance. Filter position was confirmed by contrast-enhanced CT and digital subtraction angiography. Filter tilt, distance to target position, and fluoroscopy time were analyzed.
A total of 10 filters were successfully implanted (five via transfemoral approach, five via transjugular approach) without complications. The mean distance to the target position was 0.3 cm ± 0.2. Mean filter tilt was 3.2° ± 2.3 (range, 0°-7°), without differences between deployment techniques (P = .8486). Average fluoroscopy time was 25.9 s ± 6.9 per procedure.
CT fluoroscopy-guided placement of IVC filters is safely feasible. Use of this technique may avoid the need to move critically ill patients.
Journal of vascular and interventional radiology: JVIR 08/2011; 22(11):1531-4. · 1.81 Impact Factor
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ABSTRACT: To compare the effectiveness of microwave (MW) ablation with radiofrequency (RF) ablation for treating breast tissue in a nonperfused ex vivo model of healthy bovine udder tissue.
MW ablations were performed at power outputs of 25W, 35W, and 45W using a 915-MHz frequency generator and a 2-cm active tip antenna. RF ablations were performed with a bipolar RF system with 2- and 3-cm active tip electrodes. Tissue temperatures were continuously monitored during ablation.
The mean short-axis diameters of the coagulation zones were 1.34 ± 0.14, 1.45 ± 0.13, and 1.74 ± 0.11 cm for MW ablation at outputs of 25W, 35W, and 45W. For RF ablation, the corresponding values were 1.16 ± 0.09 and 1.26 ± 0.14 cm with electrodes having 2- and 3-cm active tips, respectively. The mean coagulation volumes were 2.27 ± 0.65, 2.85 ± 0.72, and 4.45 ± 0.47 cm(3) for MW ablation at outputs of 25W, 35W, and 45W and 1.18 ± 0.30 and 2.29 ± 0.55 cm(3) got RF ablation with 2- and 3-cm electrodes, respectively. MW ablations at 35W and 45W achieved significantly longer short-axis diameters than RF ablations (P < 0.05). The highest tissue temperature was achieved with MW ablation at 45W (P < 0.05). On histological examination, the extent of the ablation zone in MW ablations was less affected by tissue heterogeneity than that in RF ablations.
MW ablation appears to be advantageous with respect to the volume of ablation and the shape of the margin of necrosis compared with RF ablation in an ex vivo bovine udder.
CardioVascular and Interventional Radiology 08/2011; 35(4):914-20. · 2.09 Impact Factor
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Satoshi Takaki,
Hiroshi Sakaguchi,
Hiroshi Anai, Toshihiro Tanaka,
Kiyosei Yamamoto,
Kengo Morimoto,
Hideyuki Nishiofuku,
Masayoshi Inoue,
Satoru Sueyoshi,
Takeshi Nagata,
Teruyuki Hidaka,
Hideo Uchida,
Kimihiko Kichikawa
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ABSTRACT: To clarify the efficacy of transcatheter hepatic sub-subsegmental, subsegmental, and segmental arterial chemoembolization using lipiodol (subseg/seg lip-TACE) for hepatocellular carcinoma (HCC), long-term outcomes of patients who had been treated using subseg/seg lip-TACE alone were retrospectively examined.
Subjects comprised 199 patients with HCC (T1/2/≥3=30/108/61; Child-Pugh A/B/C=115/52/32; Japan Integrated Staging [JIS] score≤1/2/≥3=88/64/47) who underwent subseg/seg lip-TACE using lipiodol mixed with an anticancer drug followed by injection of gelatin sponge particles. Each patient was followed-up every 3 months, and repeat subseg/seg lip-TACE and/or conventional lip-TACE was performed in cases showing recurrence. One-, 3-, 5-, 7-, and 10-year cumulative survival rates were calculated. Subgroup analyses were performed by stratifying the population according to T-factor, Child-Pugh classification, and JIS score.
Median duration of follow-up was 3.8 years (range 0.2 to 16.4). Median overall survival was 3.8 years. One-, 3-, 5-, 7- and 10-year survival rates were 91.5, 66.1, 38.8, 20.3, and 9.4% for all patients, and 95.5, 76.9, 51.9, 27.9 and 20.4% for patients with JIS≤1, respectively. Significant survival differences were found across two subgroups of staging systems (T2 vs. T3≤[P=0.0012] and JIS score≤1 vs. 2 [P=0.0036]).
This study demonstrated that subseg/seg lip-TACE is a feasible treatment for obtaining prolonged survival in patients with localized HCC showing rich vasculature. Outcomes are influenced by both tumor stage and liver function, as seen in the best prolonged survival in patients with JIS score≤1.
CardioVascular and Interventional Radiology 07/2011; 35(3):544-54. · 2.09 Impact Factor
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ABSTRACT: The combination of radiofrequency ablation (RFA) with direct current (DC) is a promising strategy to improve the efficiency of RFA. However, DC-enhanced monopolar RFA is limited by electrolytic injury at the positive-electrode site. The aim of this study was to investigate the feasibility of the DC-enhanced bipolar RFA. To obviate the need for the subcutaneous positive electrode, the DC circuit was combined with a commercially available bipolar RFA system, in which both poles of the DC circuit are connected to a single RF probe. DC was applied for 15 min and followed by RFA in bovine livers using the following various DC currents: (1) no DC (control), (2) 3V continued until the end of RFA, (3) 5V continued until the end of RFA, (4) 10V continued until the end of RFA, (5) 5V continued in the circuit with reversed pole, (6) 3V stopped after initiation of RFA, and (7) 5V stopped. Coagulation volume, temperatures at a distance of 5, 10, and 15 mm from the RF probe, mean amperage, ablation duration, applied energy, minimum impedance, and degree of tissue charring were assessed and compared (analysis of variance, Student-Newman-Keuls test). All combined DC and RFA groups did increase coagulation volume. The 10V continued group showed significantly lower applied energy, shortest ablation duration, highest minimum impedance, and highest degree of charring with the lowest coagulation volume (p<0.05). DC-enhanced bipolar RFA with both poles of the DC circuit on a single probe appears to be ineffective.
CardioVascular and Interventional Radiology 06/2011; 34(3):631-6. · 2.09 Impact Factor
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Clinical Colorectal Cancer 03/2011; 10(1):7. · 1.68 Impact Factor
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ABSTRACT: Equivalent cross-relaxation rate (ECR) imaging (ECRI) is a measurement technique that can be used to quantitatively evaluate changes in structural organization and cellular density by MRI. The aim of this study was to evaluate the correlation between the ECR value and cellular density in the rabbit VX2 tumor model.
Five rabbits implanted with 10 VX2 tumors in the femur muscles were included in this study. We adopted the off-resonance technique with a single saturation transfer pulse frequency of 7 ppm downfield from water resonance. The ECR value was defined as the percentage of signal loss between the unsaturated and saturated images. ECR images were constructed based on the percentage of the ECR value. Pathological specimens were divided into 34 areas and classified into two groups: the viable group and the necrotic group. ECR values were measured and compared between groups. The correlation between the ECR value and cellular density was then determined.
The mean ECR value was significantly higher in the viable group than in the necrotic group (61.2% vs. 35.8%). The area under the curve that calculated by receiver operating characteristic curve was 0.991 at 7 ppm. The regression graph showed a linear relationship between the ECR value and cellular density; the correlation coefficient (r) was 0.858.
There is a strong association between the ECR value and cellular density in VX2 tumors and so ECRI could be a potentially useful technique for accurately depicting viable and necrotic areas.
Cancer informatics 01/2011; 10:227-32.
