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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Acute Thrombocytopenia: An Unusual Complication Occurring After Drug-Eluting Microspheres Transcatheter Hepatic Chemoembolization

Image-guided transcatheter hepatic chemoembolization (TACE) is accepted worldwide as an effective treatment for patients with unresectable hepatocellular carcinoma and liver metastases from neuroendocrine tumors, colorectal carcinomas, and uveal melanomas. Although the technique is relatively safe, it has been associated with several complications. We report the cases of two patients with colorectal liver metastases who developed acute thrombocytopenia a few hours after TACE. To our knowledge, acute thrombocytopenia occurring after TACE with drug-eluting microspheres has not yet been reported. Here we discuss the hypothetical etiopathogenetic mechanisms.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Intra-Arterial Hepatic Chemotherapy: A Comparison of Percutaneous Versus Surgical Implantation of Port-Catheters

Purpose: To compare retrospectively the safety and efficacy of percutaneous and surgical implantations of port-catheters for intra-arterial hepatic chemotherapy (IAHC). Materials and Methods: Between January 2004 and December 2008, 126 consecutive patients (mean age 58 years) suffering from liver colorectal metastases were referred for intra-arterial hepatic chemotherapy (IAHC). Port-catheters were percutaneously implanted (P) through femoral access with the patient under conscious sedation when no other surgery was planned or were surgically implanted (S) when laparotomy was performed for another purpose. We report the implantation success rate, primary functionality, functionality after revision, and complications of IAHC. Results: The success rates of implantation were 97% (n = 65 of 67) for P and 98% (n = 58 of 59) for S. One hundred eleven patients received IAHC in our institution (n = 56P and n = 55S). Primary functionality was the same for P and S (4.80 vs. 4.82 courses), but functionality after revision was significantly higher for P (9.18 vs. 5.95 courses, p = 0.004) than for S. Forty-five complications occurred during 516 courses for P and 28 complications occurred during 331 courses for S. The rates of discontinuation of IAHC linked to complications of the port-catheters were 21% (n = 12 of 56) for P and 34% (n = 19 of 55) for S. Conclusion: Overall, significantly better functionality and similar complication rates occurred after P versus S port-catheters.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Comparing the Detectability of Hepatocellular Carcinoma by C-Arm Dual-Phase Cone-Beam Computed Tomography During Hepatic Arteriography With Conventional Contrast-Enhanced Magnetic Resonance Imaging

Purpose: To evaluate the sensitivity of dual-phase cone-beam computed tomography during hepatic arteriography (CBCTHA) for the detection of hepatocellular carcinoma (HCC) by comparing it with the diagnostic imaging 'gold standard': contrast-enhanced magnetic resonance imaging (CE-MRI) of the liver. Materials and Methods: Eighty-eight HCC lesions (mean diameter 3.9 {+-} 3.3 cm) in 20 patients (13 men, mean age 61.4 years [range 50 to 80]), who sequentially underwent baseline diagnostic liver CE-MRI and then underwent early arterial- and delayed portal venous-phase CBCTHA during drug eluting-bead transarterial chemoembolization, were evaluated. Dual-phase CBCTHA findings of each tumor in terms of conspicuity were compared with standard CE-MR images and classified into three grades: optimal, suboptimal, and nondiagnostic. Results: Seventy-seven (mean diameter 4.2 {+-} 3.4 cm [range 0.9 to 15.9]) (93.9%) of 82 tumors were detected. Sensitivity of arterial-phase (71.9%) was lower than that of venous-phase CBCTHA (86.6%) for the detection of HCC lesions. Of the 82 tumors, 33 (40.2%) and 52 (63.4%), 26 (31.7%) and 19 (23.2%), and 23 (28%) and 11 (13.4%) nodules were classed as optimal, suboptimal, and nondiagnostic on arterial- and venous-phase CBCTHA images, respectively. Seventeen (73.9%) of the 23 tumors that were not visible on arterial phase were detected on venous phase. Six (54.5%) of the 11 tumors that were not visible on venous phase were detected on arterial phase. Conclusions: Dual-phase CBCTHA has sufficient image quality to detect the majority of HCC lesions compared with the imaging 'gold standard': CE-MRI of the liver. Moreover, dual-phase CBCTHA is more useful and reliable than single-phasic imaging to depict HCC nodules.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Endovascular Repair of a Secondary Aorto-Appendiceal Fistula

Aortoenteric fistula (AEF) is an uncommon but serious complication occurring after aortic surgery and may occur at any site in the gastrointestinal tract, with the duodenum being the most common. Conventional surgical repair of secondary AEF has high mortality, whereas endovascular repair has emerged as an alternative treatment despite concerns about persistent or recurrent infection. We report the case of a 91-year old man who was admitted with rectal bleeding from an aorto-appendiceal fistula 9 years after open abdominal aortic aneurysm repair. This rare site for AEF was diagnosed on computed tomography, and we present the first case of endovascular treatment of this uncommon complication.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Hepatic Arterial Chemoembolization Using Drug-Eluting Beads in Gastrointestinal Neuroendocrine Tumor Metastatic to the Liver

Purpose: This study was designed to evaluate short (<3 months) and intermediate-term (>3 months) follow-up in patients with metastatic neuroendocrine tumor to the liver who underwent hepatic arterial chemoembolization with drug-eluting beads at a single institution. Methods: Institutional review board approval was obtained for this retrospective review. All patients who were treated with 100-300 or 300-500 {mu}m drug-eluting LC Beads (Biocompatibles, UK) preloaded with doxorubicin (range, 50-100 mg) for GI neuroendocrine tumor metastatic to the liver from June 2004 to June 2009 were included. CT and MRI were evaluated for progression using Response Evaluation Criteria In Solid Tumors (RECIST) or European Association for the Study of the Liver (EASL) criteria. Short-term (<3 months) and intermediate-term (>3 months) imaging response was determined and Kaplan-Meier survival curves were plotted. Results: Thirty-eight drug-eluting bead chemoembolization procedures were performed on 32 hepatic lobes, comprising 21 treatment cycles in 18 patients. All procedures were technically successful with two major complications (biliary injuries). At short-term follow-up (<3 months), 22 of 38 (58%) procedures and 10 of 21 (48%) treatment cycles produced an objective response (OR) with the remainder having stable disease (SD). At intermediate-term follow-up (mean, 445 days; range, 163-1247), 17 of 26 (65%) procedures and 8 of 14 (57%) treatment cycles produced an OR. Probability of progressing was approximately 52% at 1 year with a median time to progression of 419 days. Conclusions: Drug-eluting bead chemoembolization is a reasonable alternative to hepatic arterial embolization and chemoembolization for the treatment of metastatic neuroendocrine tumor to the liver.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Tumor Response and Apoptosis of N1-S1 Rodent Hepatomas in Response to Intra-arterial and Intravenous Benzamide Riboside

Purpose: Benzamide riboside (BR) induces tumor apoptosis in multiple cell lines and animals. This pilot study compares apoptosis and tumor response in rat hepatomas treated with hepatic arterial BR (IA) or intravenous (IV) BR. Methods: A total of 10{sup 6} N1-S1 cells were placed in the left hepatic lobes of 15 Sprague-Dawley rats. After 2 weeks, BR (20 mg/kg) was infused IA (n = 5) or IV (n = 5). One animal in each group was excluded for technical factors, which prevented a full dose administration (1 IA and 1 IV). Five rats received saline (3 IA and 2 IV). Animals were killed after 3 weeks. Tumor volumes after IA and IV treatments were analyzed by Wilcoxon rank sum test. The percentage of tumor and normal liver apoptosis was counted by using 10 fields of TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-stained slides at 40 Multiplication-Sign magnification. The percentage of apoptosis was compared between IV and IA administrations and with saline sham-treated rats by the Wilcoxon rank sum test. Results: Tumors were smaller after IA treatment, but this did not reach statistical significance (0.14 IA vs. 0.57 IV; P = 0.138). There was much variability in percentage of apoptosis and no significant difference between IA and IV BR (44.49 vs. 1.52%; P = 0.18); IA BR and saline (44.49 vs. 33.83%; P = 0.66); or IV BR and saline (1.52 vs. 193%; P = 0.18). Conclusions: Although differences in tumor volumes did not reach statistical significance, there was a trend toward smaller tumors after IA BR than IV BR in this small pilot study. Comparisons of these treatment methods will require a larger sample size and repeat experimentation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Spontaneous Liver Rupture After Treatment With Drug-Eluting Beads

Spontaneous rupture of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is a rare and life-threatening complication. Pathophysiologic mechanisms are not yet fully known; it is suggested that rupture is preceded by reactive tissue edema and intratumerous bleeding, leading to a rapid expansion of tumour mass with risk of extrahepatic bleeding in the case of subcapsular localisation. This case report discusses a sudden, unexpected lethal complication in a 74 year-old male patient treated with TACE using DC Bead loaded with doxorubicin (DEBDOX) in a progressive multifocal HCC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Intraluminal Radioactive Stent Compared with Covered Stent Alone for the Treatment of Malignant Esophageal Stricture

Objective: This study was designed to compare the clinical effectiveness of intraluminal radioactive stent loaded with iodine-125 seeds implantation versus covered stent alone insertion in patients with malignant esophageal stricture. Methods: We studied two groups of patients with malignant esophageal stricture. Group A comprised 28 patients (19 men and 9 women) who underwent intraluminal radioactive stent loaded with iodine-125 seeds implantation and were followed prospectively. Group B comprised 30 patients (18 men and 12 women) who had previously received covered stent alone insertion; these patients were evaluated retrospectively. There was no crossover between the two groups during follow-up. Informed consent was obtained from each patient, and our institutional review board approved the study. The dysphagia score, overall survival rates, complication rates, and reintervention rates were compared in the two groups. Results: There were no significant differences between the two groups in terms of baseline characteristics. Stent placement was technically successful and well tolerated in all patients. The dysphagia score was improved in both groups after stent placement. The median survival was significantly longer in group A than in group B: 11 versus 4.9 months, respectively (P < 0.001). The complications of chest pain, esophageal reflux, and stent migration was more frequent in group B, but this difference did not reach statistical significance. There was no statistical difference in reintervention between two groups. Conclusions: Intraluminal radioactive stent loaded with iodine-125 seeds implantation was a feasible and practical management in treating malignant esophageal stricture and was superior to covered stent alone insertion, as measured by survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Hepatic Arterial Embolization with Doxorubicin-Loaded Superabsorbent Polymer Microspheres in a Rabbit Liver Tumor Model

Objectives: The pharmacokinetic profile after hepatic arterial embolization with superabsorbent microspheres (QuadraSpheres) loaded with doxorubicin was studied. Methods: Rabbits with hepatic VX2 tumors were treated with intra-arterial administration of QuadraSpheres loaded with doxorubicin, or transarterial chemoembolization (TACE) using doxorubicin, Lipiodol and Embospheres, or hepatic arterial infusion (HAI) of doxorubicin. Tumor specimens were evaluated by fluorescence microscopy, and plasma and tumor concentrations of doxorubicin were measured. Results: The peak plasma concentration of doxorubicin was lower in the QuadraSphere group (309.9 ng/ml) than in the HAI (673.4 ng/ml) or TACE (360.5 ng/ml) groups, suggesting higher tumor retention in the QuadraSphere group. Intratumoral doxorubicin levels declined to negligible levels at 1 and 3 days after treatment, respectively, in the HAI and TACE groups. In the QuadraSphere groups, intratumoral doxorubicin level declined after day 1, but was still detectable at 14 days after treatment and was higher than that in the other groups at 1, 3, and 7 days. Intratumoral doxorubicin fluorescence was detected at all time points in the QuadraSphere group, but only at 1 day after treatment in the TACE group. Conclusions: Hepatic arterial administration of doxorubicin-loaded QuadraSpheres enables the sustained release of doxorubicin to hepatic tumors.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2011

Enhanced Antitumor Effect of Tirapazamine Delivered Intraperitoneally to VX2 Liver Tumor-Bearing Rabbits Subjected to Transarterial Hepatic Embolization

Purpose: We evaluated the effects of the combination of Tirapazamine (TPZ), activated preferentially under hypoxic conditions, and gelatin microspheres (GMS) on the tumor growth ratio in rabbits. Methods: We assigned 20 liver tumor-bearing Japanese white rabbits to 4 equal groups. Group 1 received 1 ml of saline intra-arterially (i.a.) and 20 ml of saline intraperitoneally (i.p.; saline group). Group 2 was injected with GMS i.a. and 20 ml saline i.p. (GMS group). Group 3 received 1 ml of saline i.a. and 300 mg/m{sup 2} of TPZ i.p. (TPZ group), and group 4 was treated with GMS i.a. and 300 mg/m{sup 2} of TPZ i.p. (GMS + TPZ group). The infusion of GMS was stopped when the blood flow stagnated. Before and 7 days after treatment, the liver tumor volumes were measured as the total number of pixels on 0.3Tesla (T) magnetic resonance imaging (MRI) scans. Results: The tumor growth ratio (mean {+-} standard deviation) of the saline, GMS, TPZ, and GMS + TPZ groups was 519.15 {+-} 93.78, 279.24 {+-} 91.83, 369.78 {+-} 95.73, and 119.87 {+-} 17.62, respectively. The difference between the GMS + TPZ group and the other groups was statistically significant (P < 0.05). Conclusions: Our results show that the combination of TPZ i.p. and GMS i.a. enhanced the antitumor effect of TPZ. This procedure may represent a new alternative treatment for patients with hepatic cell carcinoma.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Switching the Loaded Agent from Epirubicin to Cisplatin: Salvage Transcatheter Arterial Chemoembolization with Drug-eluting Microspheres for Unresectable Hepatocellular Carcinoma

Purpose: There is no consensus on switching anticancer agents loaded onto drug carriers in transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). This study aimed to evaluate the safety and clinical outcomes of TACE with cisplatin-loaded microspheres (CLM-TACE) in HCC patients refractory to TACE with epirubicin-loaded microspheres (ELM-TACE). Methods: Between February 2008 and June 2010, 85 patients with unresectable HCC refractory to ELM-TACE were enrolled to undergo CLM-TACE. The number of ELM-TACE sessions until judgment of resistance ranged from 1 to 4 (median, 2.1). CLM-TACE was performed using 50-100-{mu}m superabsorbent polymer microspheres loaded with 1 mg cisplatin/1 mg microspheres together with hepatic arterial infusion of 25 mg cisplatin and 500 mg 5-fluorouracil per patient. Tumor responses were evaluated by computed tomography according to the European Association for the Study of the Liver criteria. Results: The median number of CLM-TACE treatment sessions was 1.8 (range, 1-5), and the mean total dose of cisplatin per session was 42.8 mg (range, 30.0-59.0). After 6 months, 3 (3.5%) patients achieved complete response, 31 (36.5%) had partial response, 15 (17.6%) had stable disease, and 36 (42.4%) had progressive disease. The median overall survival and time to treatment failure after initial CLM-TACE were 13.3 and 7.2 months, respectively. Overall, 9.4% of patients experienced grade 3/4 adverse events. Conclusions: witching the loaded agent from epirubicin to cisplatin is a safe, well-tolerated, and efficacious treatment strategy for salvage TACE with drug-eluting microspheres in HCC patients refractory to ELM-TACE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Combined Treatment of Large Hepatocellular Carcinoma with Transcatheter Arterial Chemoembolization and Percutaneous Ethanol Injection with a Multipronged Needle: Experimental and Clinical Investigation

Purpose: This study was designed to evaluate the usefulness of percutaneous ethanol injection (PEI) with a multipronged needle for the treatment of large hepatocellular carcinoma (HCC). An experimental animal study and a clinical investigation were performed. Methods: In the experimental study, 20 ml of 99.5% ethanol was injected into porcine liver in vivo with a multipronged needle (n = 5) or a straight needle (n = 5), and the volumes of coagulation necrosis were compared. In the clinical investigation, PEI was performed in 17 patients (10 men, 7 women; mean age 73.4 {+-} 6.7 years) with single, large HCC (mean tumor diameter, 47.2 {+-} 11.5 mm; range, 32-70 mm) by using a multipronged needle. Fifteen of 17 patients received transarterial chemoembolization (TACE) before PEI. Results: The volume of coagulation in porcine liver in vivo was significantly increased with the multipronged needle compared with the straight needle (longest perpendicular diameters, 34.2 {+-} 3.6 mm Multiplication-Sign 30.2 {+-} 3.6 mm vs. 22.6 {+-} 2.5 mm Multiplication-Sign 19 {+-} 2.2 mm, respectively; P < 0.05). In the clinical trial, initial complete response (CR) of the tumor was achieved in 17 of 17 patients, 7 of whom required two PEI sessions. During the follow-up, local recurrence was detected in 4 of 17 patients at 3-19 months after the procedure, for a rate of sustained local CR of 76%. No major complication occurred. Conclusions: Use of a multipronged needle substantially increases the volume of coagulation in vivo with respect to the conventional PEI technique. Combined TACE and PEI with multipronged needles is a safe and effective option for percutaneous treatment of single, large HCC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Stereotactic Radiofrequency Ablation (SRFA) of Liver Lesions: Technique Effectiveness, Safety, and Interoperator Performance

Purpose: To evaluate technique effectiveness, safety, and interoperator performance of stereotactic radiofrequency ablation (SRFA) of liver lesions. Methods: Retrospective review including 90 consecutive patients from January 2008 to January 2010 with 106 computed tomography-guided SRFA sessions using both single and multiple electrodes for the treatment of 177 lesions: 72 hepatocellular carcinoma (HCC) and 105 metastases with a mean size of 2.9 cm (range 0.5-11 cm). Technique effectiveness and 1-year local recurrence were evaluated by computed tomographic scans. Complications, mortality, and hospital days were recorded. The performance between an experienced and inexperienced interventional radiologist was compared. Results: The overall technique effectiveness after a single SRFA was 95.5% (93.1% for HCC and 97.1% for metastases). Four of the eight unsuccessfully treated lesions could be retreated (secondary technique effectiveness of 97.7%). Local recurrence at 1 year was 2.9%. Technique effectiveness was significantly different for lesions <5 cm (96.7%) and >5 cm (87.5%) (P = 0.044) but not for lesions <3 cm (95.9%) and 3-5 cm (100%). Compared to clear parenchymal property (97.3%), vessel vicinity (93.3%) (P = 0.349) and subcapsular (95.2%) (P = 0.532) had no, but hollow viscera vicinity (83.3%) had a significantly lower technique effectiveness (P = 0.020). Mortality rate was 0.9%. Major complications and hospital days were higher for cirrhosis Child-Pugh B (20%, 7.2 days) than Child-Pugh A (3.1%, 4.7 days) patients and for metastases (5.1%, 4.3 days). There was no significant difference in interoperator performance. Conclusions: RFA allowed for efficient, reliable, and safe ablation of large-volume liver disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Radiation Exposure in Nonvascular Fluoroscopy-Guided Interventional Procedures

Purpose: To investigate the radiation exposure in non-vascular fluoroscopy guided interventions and to search strategies for dose reduction. Materials and Methods: Dose area product (DAP) of 638 consecutive non-vascular interventional procedures of one year were analyzed with respect to different types of interventions; gastrointestinal tract, biliary interventions, embolizations of tumors and hemorrhage. Data was analyzed with special focus on the fluoroscopy doses and frame doses. The third quartiles (Q3) of fluoroscopy dose values were defined in order to set a reference value for our in-hospital practice. Results: Mean fluoroscopy times of gastrostomy, jejunostomy, right and left sided percutaneous biliary drainage, chemoembolization of the liver and embolization due to various hemorrhages were 5.9, 8.6, 13.5, 16.6, 17.4 and 25.2 min, respectively. The respective Q3 total DAP were 52.9, 73.3, 155.1, 308.4, 428.6 and 529.3 Gy*cm{sup 2}. Overall, around 66% of the total DAP originated from the radiographic frames with only 34% of the total DAP applied by fluoroscopy (P < 0.001). The investigators experience had no significant impact on the total DAP applied, most likely since there was no stratification to intervention-complexity. Conclusion: To establish Diagnostic Reference Levels (DRLs), there is a need to establish a registry of radiation dose data for the most commonly performed procedures. Documentation of interventional procedures by fluoroscopy 'grabbing' has the potential to considerably reduce radiation dose applied and should be used instead of radiographic frames whenever possible.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Embolisation of the Gastroduodenal Artery is Not Necessary in the Presence of Reversed Flow Before Yttrium-90 Radioembolisation

Introduction: The gastroduodenal artery (GDA) is usually embolised to avoid nontarget dispersal before yttrium-90 (Y{sup 90}) radioembolisation to treat liver metastases. In a minority of patients, there is retrograde flow in the GDA. The purpose of this study was to determine if there is any increased risk from maintaining a patent GDA in patients with reversed flow. Materials and Methods: A retrospective review was performed of all patients undergoing Y{sup 90} radioembolisation at our institution. The incidence of toxicities arising from nontarget radioembolisation by way of the GDA (gastric/duodenal ulceration, gastric/duodenal bleeding, and pancreatitis) and death occurring within 2 months of treatment were compared between the reversed and the antegrade GDA groups. Results: Ninety-two patients underwent preliminary angiography. Reversed GDA flow was found on angiography in 14.1% of cases; the GDA was not embolised in these patients. The GDA was coiled in 55.7% of patients with antegrade GDA flow to prevent inadvertent dispersal of radioembolic material. There was no increased toxicity related to nontarget dispersal by way of the GDA, or increased early mortality, in patients with reversed GDA flow (P > 0.05). Conclusion: In patients with reversed GDA flow, maintenance of a patent GDA before administration of Y{sup 90} radioembolisation does not increase the risk of toxicity from nontarget dispersal. Therapeutic injection, with careful monitoring to identify early vascular stasis, may be safely performed beyond the origin of the patent GDA. A patent GDA with reversed flow provides forward drive for infused particles and may allow alternative access to the hepatic circulation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Superselective Internal Radiation With Yttrium-90 Microspheres in the Management of a Chemorefractory Testicular Liver Metastasis

We treated a patient with biopsy-proven, chemotherapy-resistant testicular cancer liver metastasis using Y-90 selective internal radiation treatment. We chose yttrium-90 rather than surgery and ablation due to tumor location and size as well as the patient's clinical history. The result was marked tumor response by positron emission tomography and computed tomography as well as significant improvement of the patient's quality of life accompanied by a substantial decrease of his tumor markers.

62 RADIOLOGY AND NUCLEAR MEDICINE↗