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Purpose: To examine perceptions of interventional radiology (IR) among a group of second-year medical students and support the case for early exposure to the field in order to increase visibility and, ultimately, recruitment to this specialty., Materials and Methods: Sixty-five members of the class of 2011 from a single U.S. institution were anonymously surveyed about their opinions on IR before and after a 1-hour case-based introductory lecture., Results: Sixty-four students completed the survey in its entirety. Perception about what IR entails varied, with 52% of the students aware of IR involvement in major and potentially life-saving procedures; however, 34% believed that an interventional radiologist primarily performed "minor" procedures or "read films." Previous interaction with interventional radiologists was uncommon. Following the single, case-based introductory IR lecture, 74% of the class was eager to learn more about the specialty, with 22% interested in enrolling in a dedicated hands-on elective in IR. The perception and impression of what IR entails changed significantly for the better for 75% of the students. Before the lecture, 19% were considering IR as a career (first or second choice); this increased to 33% after the introductory lecture., Conclusions: Although medical students are aware of IR, their exposure and understanding is limited. They are keen to learn more when exposed to it. Reaching out to the medical students early in their career may help in recruiting talent and securing the specialty's growth., (Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the utility of C-arm computed tomography (CT) on treatment algorithms in patients undergoing transhepatic arterial chemoembolization for hepatocellular carcinoma (HCC)., Materials and Methods: From March 2008 to July 2008, 84 consecutive patients with HCC underwent 100 consecutive transhepatic arterial chemoembolizations with iodized oil. Unenhanced and iodinated contrast medium-enhanced C-arm CT with planar and three-dimensional imaging were performed in addition to conventional digital subtraction angiography (DSA) in all patients. The effect on diagnosis and treatment was determined by testing the hypotheses that C-arm CT, in comparison to DSA, provides (a) improved lesion detection, (b) expedient identification and mapping of arterial supply to a tumor, (c) improved characterization of a lesion to allow confident differentiation of HCC from pseudolesions such as arterioportal shunts, and (d) an improved evaluation of treatment completeness. The effect of C-arm CT was analyzed on the basis of information provided with C-arm CT that was not provided or readily apparent at DSA., Results: C-arm CT was technically successful in 93 of the 100 procedures (93%). C-arm CT provided information not apparent or discernible at DSA in 30 of the 84 patients (36%) and resulted in a change in diagnosis, treatment planning, or treatment delivery in 24 (28%). The additional information included, amongst others, visualization of additional or angiographically occult tumors in 13 of the 84 patients (15%) and identification of incomplete treatment in six (7.1%)., Conclusions: C-arm CT is a useful collaborative tool in patients undergoing transhepatic arterial chemoembolization and can affect patient care in more than one-fourth of patients., (Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.)

The use of image-guided radiation therapy in thoracic and abdominal tumors is increasing. Herein, the authors review the process of image-guided radiation therapy and describe techniques useful for optimal implantation of fiducial markers.

Purpose: To prepare for yttrium-90 ((90)Y) microsphere radioembolization therapy, digital subtraction angiography (DSA) and technetium- 99m-labeled macroaggregated albumin ((99m)Tc MAA) scintigraphy are used for treatment planning and detection of potential nontarget embolization. The present study was performed to determine if cone-beam computed tomography (CBCT) affects treatment planning as an adjunct to these conventional imaging modalities., Materials and Methods: From March 2007 to August 2008, 42 consecutive patients (21 men, 21 women; mean age, 59 years; range, 21-75 y) who underwent radioembolization were evaluated by CBCT in addition to DSA and (99m)Tc MAA scintigraphy during treatment planning, and their records were retrospectively reviewed. The contrast-enhanced territories shown by CBCT with selective intraarterial contrast agent administration were used to predict intrahepatic and possible extrahepatic distribution of microspheres., Results: In 22 of 42 cases (52%), extrahepatic enhancement or incomplete tumor perfusion seen on CBCT affected the treatment plan. In 14 patients (33%), the findings were evident exclusively on CBCT and not detected by DSA. When comparing CBCT versus (99m)Tc MAA scintigraphy, CBCT showed eight cases of extrahepatic enhancement (19%) that were not evident on (99m)Tc MAA imaging. CBCT findings directed the additional embolization of vessels or repositioning of the catheter for better contrast agent and microsphere distribution. One case of gastric ulcer from nontarget embolization caused by reader error was observed., Conclusions: CBCT can provide additional information about tumor and tissue perfusion not currently detectable by DSA or (99m)Tc MAA imaging, which should optimize (90)Y microsphere delivery and reduce nontarget embolization.

Objective: The use of imaging-guided radiation therapy (IGRT) to treat thoracic and abdominal tumors is increasing. In this article, we review the process of IGRT and describe techniques to implant fiducial markers in the optimal geometry., Conclusion: Implantation of fiducial markers can be challenging. A better understanding of the physics of IGRT can help optimize fiducial marker placement for precise tumor targeting.

Purpose: To evaluate the safety and technical success rate of percutaneous fiducial marker implantation in preparation for image-guided radiation therapy., Materials and Methods: From January 2003 to January 2008, we retrospectively reviewed 139 percutaneous fiducial marker implantations in 132 patients. Of the 139 implantations, 44 were in the lung, 61 were in the pancreas, and 34 were in the liver. Procedure-related major and minor complications were documented. Technical success was defined as implantation enabling adequate treatment planning and computed tomographic simulation., Results: The major and minor complication rates were 5% and 17.3%, respectively. Pneumothorax after lung implantation was the most common complication. Pneumothoraces were seen in 20 of the 44 lung implantations (45%); a chest tube was required in only seven of the 44 lung transplantations (16%). Of the 139 implantations, 133 were successful; in six implantations (4.3%) the fiducial markers migrated and required additional procedures or alternate methods of implantation., Conclusions: Percutaneous implantation of fiducial marker is a safe and effective procedure with risks that are similar to those of conventional percutaneous organ biopsy.

Purpose: Cross-sectional diagnostic imaging studies such as contrast-enhanced quadruple-phase helical computed tomography (CT) and contrast-enhanced magnetic resonance (MR) imaging are routinely performed to evaluate tumor response to transhepatic arterial chemoembolization. However, the true correlation between imaging characteristics and histopathologic tumor viability is not known. The aim of the present retrospective study was to determine the sensitivity and specificity of contrast-enhanced CT and contrast-enhanced MR imaging with use of histopathologic analysis., Materials and Methods: Between February 2002 and October 2005, a total of 31 patients (age, 51-74 years; mean, 60 y) who had undergone chemoembolization underwent follow-up diagnostic cross-sectional imaging before transplantation. The mean time interval between the imaging study and transplantation was 32 days (range, 1-117 d). Imaging studies were assessed for residual or recurrent tumor and were then correlated to the findings of histopathologic analysis performed on the surgical specimens at the time of transplantation., Results: The overall sensitivity and specificity rates of cross-sectional imaging studies were 35% and 64%, respectively. The overall accuracy rate of CT was 43%, with 36% sensitivity and 57% specificity. The overall accuracy rate of MR imaging was 55%, with 43% sensitivity and 75% specificity. Gross macroscopic disease was missed in one patient (9%) who underwent MR imaging and four patients (19%) who underwent CT., Conclusions: Contrast-enhanced CT and MR imaging after chemoembolization are associated with high error rates. Between the two modalities, MR has higher sensitivity and specificity and may be a preferable imaging tool for patients who have undergone chemoembolization.

Purposes: The standard medical management for patients in extremis from massive pulmonary embolism (PE) is systemic thrombolysis, but the utility of this treatment relative to catheter-directed intervention (CDI) is unknown. We evaluated the effectiveness of CDI as part of a treatment algorithm for life-threatening PE., Methods: A retrospective review was performed on 70 consecutive patients with suspected acute PE over a 10-year period (from 1997 to 2006) who had been referred for pulmonary angiography and/or intervention. The criteria for study inclusion were patients who received CDI due to angiographically confirmed massive PE and hemodynamic shock (shock index, > or = 0.9). CDI involved suction embolectomy and fragmentation with or without catheter thrombolysis., Results: Twelve patients were treated with CDI. There were seven men and five women (mean age, 56 years; age range, 21 to 80 years). Seven patients (58%) were referred for CDI after failing systemic infusion with 100 mg of tissue plasminogen activator, and five patients (42%) had contraindications to systemic thrombolysis. Catheter-directed fragmentation and embolectomy were performed in all patients (100%). Additionally, catheter-guided thrombolysis was performed in eight patients (67%). Technical success was achieved in 12 of 12 cases (100%). There were no major procedural complications (0%). Significant hemodynamic improvement (shock index, < 0.9) was observed in 10 of 12 cases (83%). The remaining two patients (17%) died secondary to cardiac arrest within 24 h. Ten of 12 patients (83%) survived and remained stable until hospital discharge (mean duration, 20 days; range, 3 to 51 days)., Conclusion: In the setting of hemodynamic shock from massive PE, CDI is potentially a life-saving treatment for patients who have not responded to or cannot tolerate systemic thrombolysis.

Two cases of complications secondary to the use of microwave ablation (MWA) in non-small-cell lung cancer (NSCLC) are discussed herein. The first case involves a 62-year-old man with stage IB NSCLC who declined surgery and pursued MWA. Within 7 months, he had residual disease at the MWA treatment site, and surgery was performed. The patient was found to have pleural and chest wall involvement, making complete resection impossible. The second case involves an 86-year-old woman with a second local recurrence of NSCLC and previous treatment including surgery and chemoradiation therapy. She was initially a surgical candidate but declined surgery and pursued MWA. Within 6 months, she had residual disease at the MWA treatment site. A second MWA was performed, and she developed a large cavitary abscess at the MWA site and had subsequent clinical decline. Less invasive ablation therapies and stereotactic radiosurgery are being developed for patients with inoperable lung cancer. Because these modalities have recently been developed, trials that clearly show efficacy and survival benefit are yet to be completed. Ablation procedures can result in complications, including residual disease and cavitary lesions susceptible to infection. These cases highlight the caution that should still be observed when recommending lung ablation strategies and the importance of selecting appropriate patients.

Purpose: Transarterial chemoembolization (TACE) has become a standard treatment option for patients with unresectable hepatocellular carcinoma (HCC). This retrospective study evaluated the safety and efficacy of TACE in patients at high risk with increased serum bilirubin level, low serum albumin level, poor hepatic reserve, or compromised hepatopetal flow in the portal vein (PV)., Materials and Methods: A total of 52 patients underwent 65 high-risk procedures. Thirty patients treated with 38 procedures (57.7% of patients and 58.5% of procedures) had serum bilirubin levels of 2-3 mg/dL (ie, moderate elevation) and 22 patients treated with 27 procedures (42.3% and 41.5%) had a serum bilirubin level of at least 3 mg/dL (ie, considerable elevation). Forty patients (76.9%) had serum albumin levels less than 3.5 mg/dL. Thirteen recipients of 15 procedures (25% and 20%) had portal diversion or obstruction. Twenty-four patients (46.2%) had a Child-Pugh (CP) score of 8 or less and 28 patients (53.8%) had a CP score of at least 9 at the time of TACE. Thirty patients (57.7%) had focal tumors and 22 patients (42.3%) had multifocal or infiltrative disease. Superselective chemoembolization could be performed in 37 procedures (56.9%); lobar chemoembolization was performed in the remaining 28 (43.1%)., Results: The 30-day mortality rate was 7.7% and the procedure-related morbidity rate was 10.8%. Patients with multifocal disease and lobar embolization had significantly higher mortality rates (P=.03). Individual factors such as serum bilirubin, serum albumin, and PV flow did not affect outcomes significantly. The 1- and 2-year survival rates in patients with focal disease were 67.9% and 37.7%, respectively, compared with 19.6% and 0% in patients with multifocal disease (P<.0001)., Conclusions: TACE in patients considered at high risk does not necessarily incur a higher incidence of morbidity or mortality. Patient selection should be based on extent of disease, and these tumors should be treated selectively at a segmental level if possible.

Transjugular intrahepatic portosystemic shunt (TIPS) is frequently complicated by hepatic encephalopathy. When medical therapy fails, TIPS narrowing and resultant increase in the portosystemic pressure gradient and blood flow to the liver is performed in order to reverse the encephalopathy. We present a method for reducing the TIPS using a polytetrafluoroethylene-covered balloon expandable stent placed over a self-expanding stent. This results in a narrowed TIPS that not only rapidly increases the portosystemic gradient but also can be adjusted by dilating the balloon expandable stent. This method was successful in narrowing the patient's TIPS, acutely increasing the portosystemic gradient and reversing the hepatic encephalopathy.

Interventional radiology techniques made possible by the antithrombotic properties of heparin have revolutionized treatment for a myriad of disorders. Newer low-molecular-weight heparins (LMWHs) offer several advantages over unfractionated heparin (UFH), especially in chronic settings. They are increasing in popularity for use during vascular procedures. However, LMWH shares limitations with UFH such as heterogeneity, nonspecificity, and induction of thrombocytopenia. These drawbacks have led to a search for the next generation of antithrombotic agents. Homogeneous drugs targeting specific coagulation cascade molecules are now available. The number of alternative anticoagulant drug combinations presents clinicians with a confusing array of choices. The strengths and weaknesses of UFH, LMWH, and direct antithrombin agents are presented. The promising future of LMWH and hirudins is discussed.

Purpose: Selective arterial embolization of renal angiomyolipomas (AMLs) was performed to prevent hemorrhage in patients with AMLs larger than 4 cm. This study was conducted to evaluate the long-term efficacy of AML embolization., Materials and Methods: Nineteen patients underwent embolization for 30 renal AMLs between July 1991 and June 2002. Of these, 10 patients had tuberous sclerosis (TS) with multiple AMLs and nine patients had a solitary sporadic AML. Embolization was performed with use of ethanol mixed with iodized oil (Ethiodol) in 29 tumors; coils were used in addition to the ethanol/Ethiodol mixture in one case. All tumors were completely embolized according to angiographic criteria including vascular stasis and absence of arterial feeders. The efficacy of embolization was determined over a mean follow-up period of 51.5 months (range, 6-132 months). Recurrence was defined as an increase in tumor size of greater than 2 cm on follow-up imaging and/or recurrent symptoms that required repeat embolization. An institutional review board exemption was obtained to perform this retrospective study., Results: Embolization of the renal AMLs was technically successful in all 19 patients and for all 30 lesions. AML recurrence was noted in 31.6% of patients (n = 19) and for 30% of lesions overall (n = 9). Six of 10 patients in the TS group had AML recurrences. No recurrences occurred in the patients with sporadic AML. In the TS group of 10 patients, there was a total of 21 AMLs and the overall tumor recurrence rate was 42.9% (nine of 21). Six lesions in four patients had to be reembolized because of recurrent symptoms, including one hemorrhage, and three lesions in two patients required repeat embolization because of a greater than 2 cm increase in size. The median time interval from embolization to recurrence was 78.7 months (range, 13-132 months). Statistical testing with use of the Fisher exact test demonstrated that patients with TS were significantly more likely to develop recurrence than those without TS (P = .01)., Conclusions: Transarterial embolization is effective in preventing hemorrhage in patients with renal AMLs. However, long-term follow-up revealed a high AML recurrence rate in patients with TS. Lifelong surveillance for recurrence after AML embolization is essential in patients with TS.

Major advances in the field of liver transplantation have led to an increase in both graft and patient survival rates. Despite increased graft survival rate, biliary complications lead to significant postoperative morbidity and even mortality. A multidisciplinary approach to these complications is critical. As part of the team approach, less invasive techniques used by the interventional radiologist have an increasing role in the management of complications after liver transplantation. This paper will review the current role of the interventionalist in management of biliary complications.

Intracranial chondrosarcomas have a predilection for the skull base, for which CT and MR imaging findings have been described. We present a rare case of primary chondrosarcoma arising from the falx in a young woman with no history of radiation. The CT, conventional MR imaging, perfusion MR imaging, and digital subtraction angiography findings are described.