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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 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Systemic Arterial Supply to the Normal Basal Segments of the Left Lower Lobe of the Lung-Treatment by Coil Embolization-and a Literature Review

We report the case of a 24-year-old woman with systemic arterial supply to the normal basal segments of the left lower lobe of the lung. She experienced repeated episodes of hemoptysis. In this patient, the normal pulmonary arteries were absent in the affected segments. The aberrant artery arising from the descending thoracic aorta was embolized using metallic coils. The patient's recovery was uneventful, except that she had mild chest pain for 3 days after the procedure. Her symptom has not recurred since 1 year follow-up. Although proximal occlusion of the aberrant artery was observed, pulmonary infarction or necrosis of the affected segments was not shown on follow-up computed tomography. Transarterial embolization can be an alternative treatment option for patients with this rare congenital anomaly.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Cutaneous Bronchobiliary Fistula Treated with Tissucol Sealant

Bronchobiliary fistula is a rare and is an uncommon but severe complication of hydatid disease of the liver. Treatment has traditionally been surgical resection, but embolization and stent placement have been described. The invasive method seems to be a key component of patient treatment. We describe a case of a 58-year-old woman who, 25 years before, had undergone surgery for a hydatid cyst. A total cystectomy without previous puncture or parasite extraction was carried out. The lower aspect of the cyst was found to be completely perforated over the biliary duct. During the postoperative course, the patient had subphrenic right-sided pleural effusion and biliary fistula that subsided with medical treatment. Afterward, the patient came to the outpatient area of our hospital complaining of leakage of purulent exudate through the cutaneous opening, pain located on the right hypochondrium radiating to the right hemithorax, malaise, fever, chronic cough, and occasional vomiting of bile. Fistulography revealed an anfractuous cavity communicating with a residual cystic cavity on the right hepatic lobe. We observed communication with the intrahepatic canaliculi. Computed tomographic scan revealed a fistulous tract on the anterior liver border through the abdominal wall. There were no posttreatment complications. The patient is asymptomatic.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

CT-Guided Thrombin Injection to Control Rapid Expansion of Ascending Aortic False Aneurysm 15 Months After Bentall-Bono Operation

We report a case of 57-year-old man treated emergently with CT-guided local thrombin injection as the first, life-saving step for control rapid expansion of the aortic pseudoaneurysm. Fifteen months earlier, he was operated on for ascending aortic true aneurysm and coronary artery disease. Upon admission, he had an anterior thoracic wall pulsatile tumor. Due to critical status, definite surgery was postponed and thrombin was injected close to the origin of pseudoaneurysm. It controlled successfully, bleeding from the ascending aorta and enabled the patient to survive the acute phase.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Ultrasound-Guided Percutaneous Drainage of Neonatal Pyometrocolpos Under Local Anesthesia

Hydrometrocolpos is an uncommon congenital disorder with cystic dilatation of the vagina and uterus that occurs as a result of accumulated secretions from the reproductive tract due to distal genital tract obstruction. Secondary infection may also occur, resulting in pyometrocolpos, a potentially lethal disease. Immediate drainage of the cystic mass in patients determined to have pyometrocolpos is required to prevent or treat uropathy and septicemia until definitive corrective surgery can be performed. We report an unusual cause of obstructive uropathy in three infants: pyometrocolpos due to lower genital tract atresia. Ultrasound-guided percutaneous drainage of the pyometrocolpos resulted in dramatically improved clinical and laboratory findings in these patients. Ultrasound-guided percutaneous drainage under local anesthesia is a simple, minimally invasive, safe, and effective procedure that facilitates later successful corrective surgery and avoids the need for more complex drainage procedures.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Arterial Distribution of Calibrated Tris-Acryl Gelatin and Polyvinyl Alcohol Embolization Microspheres in Sheep Uterus

The purpose of this study was to compare, after embolization, the distribution in the uterine arterial vasculature of tris-acryl gelatin microspheres (TGMS) and polyvinyl alcohol microspheres (PVAMS). A limited bilateral uterine artery embolization was performed in six adult sheep under fluoroscopic control by injecting in each uterine artery 0.25 ml of 500- to 700-{mu}m TGMS of PVAMS suspended in 50/50 saline/contrast medium. Sacrifices were performed 1 week after embolization and uteri were analyzed histologically. The number and size of microspheres and vessels were measured, as well as the histological location according to a classification in four zones of the uterus. One hundred sixty-five vessels (69 vessels occluded with TGMS and 96 vessels occluded with PVAMS) were measured. The size of the occluded vessels decreased significantly from proximal to distal zones of the uterine vasculature (P < 0.0001). The location of TGMS and PVAMS within the vasculature was significantly different (P < 0.0001) since PVAMS blocked significantly more distally than TGMS. Deformation of the microspheres within the tissue was greater for PVAMS (18.0% {+-} 12.3%) than for TGMS (8.7% {+-} 9.2%) (P < 0.0001). In conclusion, PVAMS have a more distal distribution in the sheep uterine vasculature, compared to TGMS. Such differences in partition, already described in the kidney embolization model, can ultimately explain the different clinical outcome reported with these two types of microspheres in uterine fibroid embolization.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Diaphragmatic Hernia After Radiofrequency Ablation for Hepatocellular Carcinoma

We describe a 71-year-old woman with a hepatocellular carcinoma who underwent percutaneous radiofrequency ablation (RF) with a single internally cooled electrode under computed tomography (CT) fluoroscopic guidance. Nine months after the procedure, CT images showed herniation of the large intestine into the right pleural cavity. To our knowledge this complication of RF performed with a single internally cooled electrode under CT guidance has not been previously reported.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Observation of Intravascular Changes of Superabsorbent Polymer Microsphere (SAP-MS) with Monochromatic X-Ray Imaging

This study was designed to evaluate the intravascular transformation behavior of superabsorbent polymer microsphere (SAP-MS) in vivo macroscopically by using monochromatic X-ray imaging and to quantitatively compare the expansion rate of SAP-MS among different kinds of mixtures. Fifteen rabbits were used for our study and transcatheter arterial embolization (TAE) was performed for their auricular arteries using monochromatic X-ray imaging. We used three kinds of SAP-MS (particle diameter 100-150 {mu}m) mixture as embolic spherical particles: SAP-MS(H) absorbed with sodium meglumine ioxaglate (Hexabrix 320), SAP-MS(V) absorbed with isosmolar contrast medium (Visipaque 270), and SAP-MS(S) absorbed with 0.9% sodium saline. The initial volume of SAP-MS particles just after TAE and its final volume 10 minutes after TAE in the vessel were measured to calculate the expansion rate (ER) (n = 30). Intravascular behavior of SAP-MS particles was clearly observed in real time at monochromatic X-ray imaging. Averaged initial volumes of SAP-MS (H) (1.24 x 10{sup 7} {mu}m{sup 3}) were significantly smaller (p < 0.001) than those of SAP-MS (V) (5.99 x 10{sup 7} {mu}m{sup 3}) and SAP-MS (S) (5.85 x 10{sup 7} {mu}m{sup 3}). Averaged final volumes of SAP-MS (H) were significantly larger than averaged initial volumes (4.41 x 10{sup 7} {mu}m{sup 3} vs. 1.24 x 10{sup 7} {mu}m{sup 3}; p < 0.0001, ER = 3.55). There were no significant difference between averaged final volumes and averaged initial volumes of SAP-MS (V) and SAP-MS (S). SAP-MS (H), which first travels distally, reaches to small arteries, and then expands to adapt to the vessel lumen, is an effective particle as an embolic agent, causing effective embolization.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Comparison of Hemostatic Durability between N-Butyl Cyanoacrylate and Gelatin Sponge Particles in Transcatheter Arterial Embolization for Acute Arterial Hemorrhage in a Coagulopathic Condition in a Swine Model

This study was designed to compare the efficacy of transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) or gelatin sponge particles (GSP) for acute arterial bleeding in a coagulopathic condition using a swine model. Four healthy swine were divided into two coagulopathic conditions: mild and severe. Five hemorrhages were created in each swine (10 hemorrhages per coagulopathy). Mild coagulopathy was achieved by bloodletting 10% of the total circulatory whole blood and preserving activated clotting time (ACT) less than 200 s (ACT < 200 s state); severe coagulopathy was achieved by bloodletting 30% and preserving ACT > 400 s (ACT > 400-second state). For each state, of ACT < 200 s or ACT > 400 s, TAE was conducted with GSP or NBCA to control five hemorrhages arising from artificially created renal and splenic injuries. Angiography immediately after TAE with GSP or NBCA showed complete occlusion in both coagulopathic conditions. In the ACT < 200-second state, follow-up angiography at 5-30 min after TAE with GSP or NBCA showed no evidence of recurrent hemorrhage. In the ACT > 400-second state, follow-up angiography showed recurrent hemorrhage in four (80%) of the five hemorrhages embolized with GSP and in one (20%) of the five hemorrhages embolized with NBCA. Microscopically, red thrombi were observed densely surrounding GSP in mild coagulopathy but were scarce in severe coagulopathy. In a condition with severe coagulopathy, TAE with NBCA was more effective in durability to cease active arterial bleeding than with GSP.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Vascular Access in Children

Establishment of stable vascular access is one of the essential and most challenging procedures in a pediatric hospital. Many clinical specialties provide vascular service in a pediatric hospital. At the top of the 'expert procedural pyramid' is the pediatric interventional radiologist, who is best suited and trained to deliver this service. Growing awareness regarding the safety and high success rate of vascular access using image guidance has led to increased demand from clinicians to provide around-the-clock vascular access service by pediatric interventional radiologists. Hence, the success of a vascular access program, with the pediatric interventional radiologist as the key provider, is challenging, and a coordinated multidisciplinary team effort is essential for success. However, there are few dedicated pediatric interventional radiologists across the globe, and also only a couple of training programs exist for pediatric interventions. This article gives an overview of the technical aspects of pediatric vascular access and provides useful tips for obtaining vascular access in children safely and successfully using image guidance.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

A New Soluble Gelatin Sponge for Transcatheter Hepatic Arterial Embolization

To prepare a soluble gelatin sponge (GS) and to explore the GS particles (GSPs) that inhibit development of collateral pathways when transcatheter hepatic arterial embolization is performed. The approval of the Institutional Committee on Research Animal Care of our institution was obtained. By means of 50 and 100 kDa of regenerative medicine-gelatin (RM-G), RM-G sponges were prepared by freeze-drying and heating to temperatures of 110-150{sup o}C for cross-linkage. The soluble times of RM-GSPs were measured in vitro. Eight swine for transcatheter hepatic arterial embolization were assigned into two groups: six received 135{sup o}C/50RM-GSPs, 125{sup o}C/100RM-GSPs, and 138{sup o}C/50RM-GSPs, with soluble time of 48 h or more in vitro; two swine received Gelpart GSPs (G-GSPs) with insoluble time of 14 days as a control. Transarterial chemoembolization was performed on two branches of the hepatic artery per swine. RM-GSPs heated at temperatures of 110-138{sup o}C were soluble. Mean soluble times of the RM-GSPs increased with higher temperature. Hepatic branches embolized with G-GSP remained occluded after 6 days, and development of collateral pathways was observed after 3 days. Hepatic branches embolized with 135{sup o}C/50RM-GSP and 125{sup o}C/100RM-GSP remained occluded for 4 h, and recanalization was observed after 1 day. Hepatic branches embolized with 138{sup o}C/50RM-GS remained occluded for 1 day, and recanalization was observed after 2 days with no development of collateral pathways. In RM-GSs with various soluble times that were prepared by modulating the heating temperature, 138{sup o}C/50RM-GSP was the soluble GSP with the longest occlusion time without inducing development of collateral pathways.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Ischemic Effects of Transcatheter Arterial Embolization with N-Butyl Cyanoacrylate-Lipiodol on the Colon in a Swine Model

This study was designed to assess the safety of transcatheter arterial embolization (TAE) with n-butyl cyanoacrylate-lipiodol (NBCA-Lp) for the large bowel and to investigate the vital response to NBCA-Lp in a swine model. In nine swine, nine arteries nourishing the colon were embolized with NBCA-Lp (1 ml of NBCA mixed with 4 ml of lipiodol): sigmoid-rectal branch artery in six swine, right colic branch artery in two, and middle colic branch artery in one. The amount of NBCA-Lp was 0.1-0.4 ml. Sacrifice was conducted 3 days after TAE to identify histological infarction. Classification was conducted retrospectively: group A, vasa recta without NBCA-Lp embolization despite TAE; group B, three or fewer vasa recta with NBCA-Lp embolization; and group C, five or more vasa recta with NBCA-Lp embolization. In one swine in group A, no necrotic focus was observed. In group B, three of four swine experienced no ischemic damage. The remaining one swine experienced necrosis of mucosal and submucosal layers in one-fourth of the circumference. In group C, all four swine with marginal artery and five vasa recta or more embolized experienced total necrosis of mucosa, submucosa, and smooth muscle layers of the whole colonic circumference. Significant difference on the extent of ischemic damage was observed between groups B and C (P < 0.05). Microscopically, NBCA-Lp induced acute vasculitis. Embolization of three or fewer vasa recta with NBCA-Lp induced no ischemic damage or limited necrosis, whereas embolization of five or more vasa recta with NBCA-Lp induced extensive necrosis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Thermal Ablation of Lung Tissue: In Vivo Experimental Comparison of Microwave and Radiofrequency

This study was designed to compare feasibility, safety, and effectiveness of microwave (MW) ablation versus radiofrequency (RF) ablation of lung tissue in a rabbit model. Twenty New Zealand White rabbits were submitted to MW (n = 10, group A) or RF ablation (n = 10, group B). The procedures were performed with a prototype MW ablation device with a 1.6-cm radiating section antenna (Valleylab MW Ablation System) and with a 2-cm exposed-tip RF electrode (Cool-tip RF Ablation System). At immediate computed tomography increase in density, maximum diameters (D1-D3) of ablation zones were measured and ablation volume was calculated. Histopathologic assessment was performed 3 and 7 days after the procedure. Technical success was achieved in nine of 10 rabbits in each group. One death occurred in group B. Complications included pneumothorax (group A, n = 4; group B, n = 4), abscess (group A, n = 1; group B, n = 1), and thoracic wall burn (group A, n = 4). No significant differences were demonstrated in attenuation increase (P = 0.73), dimensions (P = 0.28, 0.86, 0.06, respectively, comparing D1-D3) and volume (P = 0.17). At histopathology, ablation zones were similar, with septal necrosis, edema, hemorrhage, and peripheral lymphocytic infiltrate. Complete thrombosis of more than 90% of vessels up to 2 mm in diameter was depicted at the periphery of the ablation zone in group A specimens. In group B specimens, complete thrombosis was depicted in 20% of vessels. Feasibility and safety of MW and RF ablation are similar in a lung rabbit model. MW ablation produces a greater damage to peripheral small vessels inducing thrombosis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Predictors of Reintervention After Endovascular Repair of Isolated Iliac Artery Aneurysm

The objective of this study was to identify factors predicting the need for reintervention after endovascular repair of isolated iliac artery aneurysm (IIAA). We reviewed prospectively collected database records of all patients who underwent endovascular repair of IIAA between 1999 and 2008. Detailed assessment of the aneurysms was performed using computed tomography angiography (CTA). Follow-up protocol included CTA at 3 months. If this showed no complication, then annual duplex scan was arranged. Multivariate analysis and analysis of patient survival and freedom from reintervention were performed using Kaplan-Meier life tables. Forty IIAAs (median diameter 44 mm) in 38 patients were treated (all men; median age 75 years), and median follow-up was 27 months. Endovascular repair of IIAA was required in 14 of 40 aneurysms (35%). The rate of type I endoleak was significantly higher with proximal landing zone (PLZ) diameter >30 mm in the aorta or >24 mm in the common iliac artery or distal landing zone (DLZ) diameter >24 mm (P = 0.03, 0.03, and 0.0014, respectively). Reintervention rate (RR) increased significantly with increased diameter or decreased length of PLZ; increased DLZ diameter; and endovascular IIAA repair (P = 0.005, 0.005, 0.02, and 0.02 respectively); however, RR was not significantly affected by length of PLZ or DLZ. Freedom-from-reintervention was 97, 93, and 86% at 12, 24, and 108 months. There was no in-hospital or aneurysm-related mortality. Endovascular IIAA repair is a safe treatment option. Proper patient selection is essential to decrease the RR.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Massive Pulmonary Embolism: Treatment with the Rotarex Thrombectomy System

This study was designed to evaluate the efficacy and safety of percutaneous mechanical thrombectomy (PMT) for acute massive pulmonary embolism (PE). Fourteen patients (8 men, 6 women) with a mean age of 55.4 (range, 38-71) years with acute massive PE were initially diagnosed by computed tomography (CT) and confirmed by pulmonary angiography. All patients presented with acute PE symptoms and hemodynamic compromise. Each patient was treated with Straub Rotarex thrombectomy device and five patients received additional thrombolysis. Technique success and clinical improvement were achieved in all patients without major complications. The mean pulmonary artery pressure (PAP) decreased from 37.6 {+-} 6.6 to 29 {+-} 6.4 mmHg (P < 0.01) after PMT. Partial arterial pressures of O{sub 2} (PaO{sub 2}) increased from 61.1 {+-} 9.2 to 88 {+-} 5.1 mmHg (P < 0.01). The Miller index was 0.67 {+-} 0.11 and 0.37 {+-} 0.13 (P < 0.01), respectively, before and after PMT (P < 0.01). Eleven patients had no recurrence of PE on a mean follow-up of 28.3 months, whereas the other three patients were lost to follow-up. The preliminary experience in our series suggests that the Straub Rotarex thrombectomy device, which has been utilized in peripheral arteries, also is useful for the treatment of acute massive PE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Occlusion of Arteriovenous Fistulas of In-Situ Saphenous Vein Bypass Grafts Using the Amplatzer Vascular Plug 4: Initial Experience

We examined the safety and efficacy of vessel occlusion of the Amplatzer Vascular Plug 4 (AVP-4) in patients with arteriovenous fistulas after in-situ saphenous vein bypass grafts. We treated 18 fistulas of seven patients (four women, mean {+-} standard deviation age 76 {+-} 7 years, range 63-88 years). All fistulas were detected within 14 days after surgery. Initial diagnosis and follow-up was established by sonography. We measured the diameter of the feeding vessel and the time of vessel occlusion after plug deployment. Additionally, we recorded procedure time and the dose area product. Additional interventional procedures were necessary in three patients. We successfully used 19 AVP-4 for occlusion of all fistulas without thromboembolic complications. There was no need for recapturing the device, and we did not observe dislocation. Mean occlusion time was 9.6 min (range 5-22 min). Mean diameter of the feeding vessels was 3.5 mm (range 2.6-5.1 mm). Plug sizes ranged from 4-8 mm (mean 5.5 mm) resulting in an oversizing of 33-88%. Mean procedure time for patients with and without additional intervention was 91 {+-} 38 min and 35 {+-} 18 min, respectively. Mean dose area product was 11,790 cGy/cm{sup 2} (range 1,850-23,500 cGy/cm{sup 2}). Permanent occlusion of the fistulas was confirmed by ultrasound after a mean follow-up of 4 months (1-6 months). Occlusion of arteriovenous fistulas with an AVP-4 seems to be effective and safe in patients with in-situ saphenous vein bypass grafts. The AVP-4 is well suited for this purpose because of the appropriate diameter of the feeding vessels.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Direct Current Combined With Bipolar Radiofrequency Ablation: An Ex Vivo Feasibility Study

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.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Renal Artery Embolization Combined With Radiofrequency Ablation in a Porcine Kidney Model: Effect of Small and Narrowly Calibrated Microparticles as Embolization Material on Coagulation Diameter, Volume, and Shape

The purpose of this study was to evaluate the effect of renal artery embolization with small and narrowly calibrated microparticles on the coagulation diameter, volume, and shape of radiofrequency ablations (RFAs) in porcine kidneys. Forty-eight RFAs were performed in 24 kidneys of 12 pigs. In 6 animals, bilateral renal artery embolization was performed with small and narrowly calibrated microparticles. Upper and lower kidney poles were ablated with identical system parameters. Applying three-dimensional segmentation software, RFAs were segmented on registered 2 mm-thin macroscopic slices. Length, depth, width, volume{sub s}egmented, and volume{sub c}alculated were determined to describe the size of the RFAs. To evaluate the shape of the RFAs, depth-to-width ratio (perfect symmetry-to-lesion length was indicated by a ratio of 1), sphericity ratio (perfect sphere was indicated by a sphericity ratio of 1), eccentricity (perfect sphere was indicated by an eccentricity of 0), and circularity (perfect circle was indicated by a circularity of 1) were determined. Embolized compared with nonembolized RFAs showed significantly greater depth (23.4 {+-} 3.6 vs. 17.2 {+-} 1.8 mm; p < 0.001) and width (20.1 {+-} 2.9 vs. 12.6 {+-} 3.7 mm; p < 0.001); significantly larger volume{sub s}egmented (8.6 {+-} 3.2 vs. 3.0 {+-} 0.7 ml; p < 0.001) and volume{sub c}alculated (8.4 {+-} 3.0 ml vs. 3.3 {+-} 1.1 ml; p < 0.001); significantly lower depth-to-width (1.17 {+-} 0.10 vs. 1.48 {+-} 0.44; p < 0.05), sphericity (1.55 {+-} 0.44 vs. 1.96 {+-} 0.43; p < 0.01), and eccentricity (0.84 {+-} 0.61 vs. 1.73 {+-} 0.91; p < 0.01) ratios; and significantly greater circularity (0.62 {+-} 0.14 vs. 0.45 {+-} 0.16; p < 0.01). Renal artery embolization with small and narrowly calibrated microparticles affected the coagulation diameter, volume, and shape of RFAs in porcine kidneys. Embolized RFAs were significantly larger and more spherical compared with nonembolized RFAs.

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