Chronic abdominal pain and Budd-Chiari syndrome: A relentless quest for an underlying neoplastic etiology.

In this article, we report on a 62-year-old non-cirrhotic male presenting to the emergency department (ED) with chronic abdominal pain, anorexia, and weight loss. Upon initial presentation, physical exam was unremarkable, other than for sarcopenia and splenomegaly. Initial imaging studies revealed a large thrombosis from the iliac vein to the right atrium of the heart. Following discharge, the patient re-consulted to the ED four months later and was re-admitted in renal failure and ascites. The diagnosis of Budd-Chiari syndrome (BCS) was established. Positive immunohistochemistry confirmed a neoplastic ideology of epithelial nature. This case offers a unique perspective on the clinical presentation of secondary BCS, necessitating a consideration in the differential diagnosis of a para-vascular cause. In this case, chronic abdominal pain, often overlooked, may necessitate further workup to establish a clinical diagnosis.

Utilization of serum D-dimer assays prior to computed tomography pulmonary angiography scans in the diagnosis of pulmonary embolism among emergency department physicians: a retrospective observational study.

BACKGROUND: A variety of evidence-based algorithms and decision rules using D-Dimer testing have been proposed as instruments to allow physicians to safely rule out a pulmonary embolism (PE) in low-risk patients. OBJECTIVE: To describe the prevalence of D-Dimer utilization among emergency department (ED) physicians and its impact on positive yields and utilization rates of Computed Tomography Pulmonary Angiography (CTPA). METHODS: Data was collected on all CTPA studies ordered by ED physicians at three sites during a 2-year period. Using a chi-square test, we compared the diagnostic yield for those patients who had a D-Dimer prior to their CTPA and those who did not. Secondary analysis was done to examine the impact of D-Dimer testing prior to CTPA on individual physician diagnostic yield or utilization rate. RESULTS: A total of 2811 CTPAs were included in the analysis. Of these, 964 CTPAs (34.3%) were ordered without a D-Dimer, and 343 (18.7%) underwent a CTPA despite a negative D-Dimer. Those CTPAs preceded by a D-Dimer showed no significant difference in positive yields when compared to those ordered without a D-Dimer (9.9% versus 11.3%, p = 0.26). At the individual physician level, no statistically significant relationship was found between D-Dimer utilization and CTPA utilization rate or diagnostic yield. CONCLUSION: This study provides evidence of suboptimal adherence to guidelines in terms of D-Dimer screening prior to CTPA, and forgoing CTPAs in patients with negative D-Dimers. However, the lack of a positive impact of D-Dimer testing on either CTPA diagnostic yield or utilization rate is indicative of issues relating to the high false-positive rates associated with D-Dimer screening.

Transabdominal Direct Sac Puncture Embolization of Type II Endoleaks after Endovascular Abdominal Aortic Aneurysm Repair.

PURPOSE: To determine the efficacy and safety of transabdominal direct sac puncture embolization of type II endoleaks after endovascular abdominal aortic aneurysm repair (EVAR). MATERIALS AND METHODS: This retrospective review included 30 patients (4 women, 26 men; mean age = 79.1 years) who underwent 33 transabdominal direct sac puncture embolization procedures for type II endoleaks after EVAR. Embolization agents included cyanoacrylate glue only (45.5%), glue/coils (36.4%), and Onyx with or without glue/coils (18.1%). Technical success was defined as complete endoleak embolization on intraprocedural fluoroscopy. The primary outcome was freedom of aneurysm growth, which was defined as ≤ 5% aneurysm sac volume change on follow-up computed tomography (CT) imaging or ≤ 5 mm aneurysm sac diameter change on ultrasound without definite endoflow. Aneurysm sac volumes before and after embolization were manually segmented from CT images. The procedural complication rate was calculated. RESULTS: Technical success was achieved in 97% of patients (29/30). Follow-up imaging was available in 27 patients (25 CT; 2 ultrasound), and mean imaging follow-up duration was 15.5 months. Freedom of aneurysm growth was achieved in 85.2% of patients (23/27) after 1 or more embolization procedures. Median fluoroscopic and procedure times were 11.3 minutes and 90 minutes, respectively. The complication rate was 9.1% (3/33) and included 1 case of nontarget embolization with transient neuropraxia and 2 self-limiting rectus sheath hematomas relating to the percutaneous puncture site. No aneurysm-related mortality occurred during the follow-up period. CONCLUSIONS: Percutaneous transabdominal embolization is a safe and efficacious treatment for type II endoleak, with a short procedure time.

Non-contrast-enhanced MR angiography in critical limb ischemia: performance of quiescent-interval single-shot (QISS) and TSE-based subtraction techniques.

PURPOSE: The aim of this study was to evaluate diagnostic performance of non-contrast-enhanced 2D quiescent-interval single-shot (QISS) and 3D turbo spin-echo (TSE)-based subtraction magnetic resonance angiography (MRA) in the assessment of peripheral arteries in patients with critical limb ischemia (CLI). MATERIALS AND METHODS: Nineteen consecutive patients (74 % male, 72.8 ± 9.9 years) with CLI underwent 2D QISS and 3D TSE-based subtraction MRA at 1.5 T. Axial-overlapping QISS MRA (3 mm/2 mm; 1 × 1 mm2) covered from the toes to the aortic bifurcation while coronal 3D TSE-based subtraction MRA (1.3 × 1.2 × 1.3 mm3) was restricted to the calf only. MRA data sets (two readers) were evaluated for stenosis (≥50 %) and image quality. Results were compared with digital subtraction angiography (DSA). RESULTS: Two hundred and sixty-seven (267) segments were available for MRA-DSA comparison, with a prevalence of stenosis ≥50 % of 41.9 %. QISS MRA was rated as good to excellent in 79.5-96.0 % of segments without any nondiagnostic segments; 89.8-96.1 % of segments in 3D TSE-based subtraction MRA were rated as nondiagnostic or poor. QISS MRA sensitivities and specificities (segmental) were 92 % and 95 %, respectively, for reader one and 81-97 % for reader two. Due to poor image quality of 3D TSE-based subtraction MRA, diagnostic performance measures were not calculated. CONCLUSION: QISS MRA demonstrates excellent diagnostic performance and higher robustness than 3D TSE-based subtraction MRA in the challenging patient population with CLI. KEY POINTS: • QISS MRA allows reliable diagnosis of peripheral artery stenosis in critical limb ischemia. • Robustness of TSE-based subtraction MRA is limited in critical limb ischemia. • QISS MRA allows robust therapy planning in PAD patients with resting leg pain.

Direct sac puncture versus transarterial embolization of type II endoleaks: An evaluation and comparison of outcomes.

Purpose To determine the outcomes of type II endoleak embolization with aneurysm sac obliteration and whether the approach - direct sac puncture or transarterial - affects outcome. Methods A retrospective review of patients who underwent endovascular aneurysm repairs and subsequent type II endoleak embolization over 10 years was performed. Twenty-three patients (median age: 73 years, range: 40-88 years) underwent 35 embolizations. Embolization was performed with the goal of obliterating both the endoleak sac and feeding vessels. Embolization agents used include cyanoacrylate glue only (48%), glue and coils (36%), coils only (13%), and other (3%). Results Mean follow-up was 21.8 months. Patients underwent an average of 1.5 embolizations, with 35% requiring more than one. Technical success rate was 89%. Freedom from aneurysm sac expansion was achieved in 91%. Freedom from type II endoleak was accomplished in 70%. There were no ruptured aneurysms during the follow-up period. Direct sac puncture and transarterial approaches had similar incidences of aneurysm sac growth ( p = 0.74), persistent type II endoleak ( p = 0.32), and complications ( p = 0.64). However, direct sac puncture had significantly shorter fluoroscopy ( p < 0.001) and total procedure times ( p < 0.001) than transarterial embolizations. Conclusion Direct sac puncture and transarterial embolization of type II endoleak with aneurysm sac obliteration are similarly effective for the prevention of aneurysm sac growth. However, direct sac puncture is our preferred approach given its significantly shorter fluoroscopic and procedural times.

Combined Coil Embolization and Foam Sclerotherapy for the Management of Varicose Veins.

BACKGROUND: We propose a novel technique for endovenous treatment of varicose veins (VVs) using combined coil embolization and foam sclerotherapy of the great saphenous vein (GSV). METHODS: A retrospective case-series analysis on patients undergoing fluoroscopically guided coil embolization of the GSV and foam sclerotherapy of the GSV and below-knee varices at a single Canadian center. RESULTS: Twenty-two patients underwent the procedure on 23 legs. Most patients (78.3%) presented for follow-up 57.2 ± 21.9 days postoperatively. Doppler studies demonstrated complete GSV occlusion in all patients. While 3 patients (13.6%) noted skin discoloration overlying the treated VVs, none complained of pain on follow-up or developed leg numbness, deep vein thrombosis, or pulmonary emboli. CONCLUSIONS: Coil embolization and foam sclerotherapy are a novel and effective treatment for VVs that uses existing and readily available angiographic equipment.

Elastic Recoil after Balloon Angioplasty in Hemodialysis Accesses: Does It Actually Occur and Is It Clinically Relevant?

Purpose To qualify and quantify elastic recoil and determine its effect on access patency. Materials and Methods Research ethics board approval was obtained and all patients signed an informed consent form. This was a prospective, nonrandomized study of mature accesses that underwent balloon percutaneous transluminal angioplasty (PTA) between January 2009 and December 2012. After PTA, completion fistulography was performed at 0-, 5-, 10-, and 15-minute intervals. From Digital Imaging and Communications in Medicine images, percentage of lesion stenosis before and after PTA was measured at each time point. A total of 76 patients (44 men, 32 women; mean age, 59.6 years) were enrolled and underwent 154 PTAs in 56 grafts and 98 fistulas. Venous elastic recoil was defined as recurrent luminal narrowing greater than 50% within 15 minutes after full effacement of the stenosis by the angioplasty balloon. Data collected included sex, age, access type and location, lesion location, length, and time to next intervention. Access patency was estimated by using Kaplan-Meier survival method, association of variables with the risk of loss of patency was assessed by using a Cox proportional hazards model, and a multiple variable model was examined by considering all variables. Results Technical success of PTA with less than 30% residual stenosis was 78%. By 15 minutes, 15.6% (24 of 154) of treated lesions recurrently narrowed by more than 50%, with a majority observed at 5 minutes (15 of 24). Technical failure of PTA was predictive of elastic recoil (P < .001), as was cephalic arch stenosis in fistulas (P = .047) and autogenous fistulas (P = .04). Elastic recoil, when it did occur, did not influence patency. Six-month primary patency was 34.8% in grafts and 47.1% in fistulas. Conclusion Venous elastic recoil after PTA of stenoses in hemodialysis access circuits is common, but its occurrence does not influence access primary patency after PTA. (©) RSNA, 2015.

The in-hospital costs of treating high-risk patients with fenestrated and branched endografts.

OBJECTIVE: This study determined the 30-day morbidity and mortality and in-hospital costs of elective fenestrated (fEVAR) and branched (bEVAR) endovascular aneurysm repairs at a single academic institution and determined factors that influence them. METHODS: All elective fEVAR or bEVAR patients treated between November 2007 and March 2014 in a Canadian academic hospital were included. Procedural details, 30-day morbidity and mortality rates, and cost of hospitalization were analyzed. Nonparametric bootstrap analysis was used to compare means between groups and calculate confidence intervals (CIs). RESULTS: There were 84 consecutive fEVAR (n = 61) and bEVAR (n = 23) procedures. The 30-day mortality was 3.3% for fEVAR and 4.3% for bEVAR. Mean hospital stay was 7.2 ± 0.8 days for fEVAR and 12.6 ± 2.2 days for bEVAR. The mean cost of the index hospitalization was $57,000 for fEVAR and $91,000 for bEVAR. Device-related costs accounted for 55% of the total costs. The occurrence of intraoperative or postoperative events were used to further divide each of the fEVAR and bEVAR groups into "complicated hospitalization" (fEVAR, n = 10; bEVAR, n = 13) and "uncomplicated hospitalization" (fEVAR, n = 51; bEVAR, n = 10) groups. Device-related costs were not significantly different between the complicated and uncomplicated hospitalization groups (mean difference [95% CI] fEVAR: $3383 [-$3405 to $9809], P = .3; and bEVAR: $1930 [-$7892 to $11,288], P = .68). However, there were significant differences between the complicated and uncomplicated hospitalization groups in hospital length of stay (mean difference [95% CI] fEVAR: 8.1 [3.0-13.2] days, P = .001; and bEVAR: 10.8 [5.9-19.9] days, P = .002) and nondevice-related costs (mean difference [95% CI,] fEVAR: $25,843 [$11,689-$43,247], P = .001; and bEVAR; $20,326 [$9362-$36,615], P = .002). CONCLUSIONS: bEVAR and fEVAR are expensive interventions. Intraoperative adverse events and postoperative systemic complications dramatically increase costs and length of stay. Measures to minimize complications will reduce hospitalization costs and improve patient outcomes.

Randomized Trial Comparing Radiologic Pigtail Gastrostomy and Peroral Image-Guided Gastrostomy: Intra- and Postprocedural Pain, Radiation Exposure, Complications, and Quality of Life.

PURPOSE: To prospectively compare radiologically created pigtail gastrostomy (PG), in which the tube is inserted directly through the abdominal wall, versus peroral image-guided gastrostomy (POG), in which the tube is inserted through the mouth. Pain profiles (primary outcome measure), fluoroscopy times, total room times, technical success, complications, and quality of life (QOL) were measured. MATERIALS AND METHODS: Sixty patients were prospectively randomized to receive 14-F PG or 20-F POG tubes. All patients received prophylactically created gastrostomies before radiation therapy for head and neck squamous-cell carcinoma. Patients receiving palliative treatment were excluded, as were those with established pharyngeal obstruction. Pain was measured by numeric rating scale (NRS) scores for 6 weeks after the procedure and by intraprocedural fentanyl and midazolam doses and postprocedural 24-h morphine doses. Fluoroscopy times, total room times, technical success, complications up to 6 months, and gastrostomy-related QOL (using the Functional Assessment of Cancer Therapy-Enteral Feeding questionnaire) were determined. RESULTS: Fifty-six patients underwent the randomized procedure. The POG group required significantly higher intraprocedural midazolam and fentanyl doses (mean, 1.2 mg and 67 µg, respectively, for PG vs 1.9 mg and 105 µg for POG; P < .001) and had significantly longer fluoroscopy times (mean, 1.3 min for PG vs 4.8 min for POG; P < .0001). NRS scores, morphine doses, total room times, technical success, complication rates, and QOL did not differ significantly between groups. The one major complication, a misplaced PG in the peritoneal cavity, followed a technical failure of POG creation. CONCLUSIONS: Despite the differences in insertion technique and tube caliber, the measured outcomes of POG and PG are comparable.

Efficacy of Ovarian Artery Embolization for Uterine Fibroids: Clinical and Magnetic Resonance Imaging Evaluations.

PURPOSE: The objective of the study was to assess the efficacy of ovarian artery embolization (OAE) treatment for symptomatic uterine leiomyomas. METHODS: A retrospective review of 17 patients who underwent OAE in conjunction with uterine artery embolization in a 6-year period (2006-2012) was performed. Ten patients had previous failed embolization, while 7 had not received any embolization therapy before. Percent uterine volume change, percent dominant fibroid volume change, and percent dominant fibroid infarction were assessed with magnetic resonance (MR) imaging. Resolution of menorrhagia, dysmenorrhea/pain, and bulk and/or pressure symptoms including urinary frequency were evaluated clinically. Change in menopausal state was also an outcome of interest. RESULTS: Mean MR imaging follow-up was performed 3 months post-OAE. MR images showed complete infarction in the majority of cases (64.7%; n = 11), with infarction rates of 90%-100% in 3 cases, 1 case with 30%-50% infarction, and 2 cases with 0%-10% infarction. Average uterine size reduction on MR was 32.3% (95% confidence interval [CI]: 22.5%-42.2%; P < .001). The average size reduction for the dominant fibroid was 42.4% (95% CI: 27.7%-57.0%; P = .01). The mean time to final follow-up visit was 11 months. At this point complete symptom resolution (menorrhagia, dysmenorrhea and bulk-related) was achieved in 82.4% (n = 14) of cases. At the final follow-up 11.8% (n = 2) of cases reported menopause. CONCLUSIONS: We observed OAE to be an effective and safe adjunct to uterine artery embolization when hypertrophic ovarian artery(ies) require intervention. However, incomplete fibroid infarction of 23% remains a concern with a potential for long-term treatment failure. In addition, long-term effect on ovarian function is uncertain.

Evaluation of percutaneous ultrasound-guided biopsies of solid mass lesions of the pancreas: a center's 10-year experience.

OBJECTIVE: To assess the efficacy and complication rates of percutaneous ultrasound (US)-guided pancreatic mass biopsy and to determine if location of the mass or method of biopsy affects efficacy. METHODS: Imaging, pathology, and clinical records of all patients undergoing percutaneous US-guided pancreatic mass sampling from January 2001 until November 2011 were reviewed. Of 88 pancreatic masses, 13 underwent fine needle aspiration (FNA) only, 60 underwent core needle biopsy only, and 15 underwent both. Diagnostic rate, sensitivity, specificity, accuracy, and positive predictive value and negative predictive value (NPV) based on location of the mass (head/neck vs. body/tail) and method of biopsy (core vs. FNA vs. combined) were determined. The final diagnosis was determined on the basis of follow-up imaging, clinical course, and/or surgical pathology. Complications were assessed by reviewing clinical notes and postprocedural imaging. RESULTS: The overall diagnostic rate, sensitivity, accuracy, and NPV of all 88 biopsies were 94%, 93%, 93%, and 57%, respectively. Five samples were nondiagnostic and considered false negatives. There were no false-positive biopsy results. No significant difference was observed in the diagnostic rate, sensitivity, accuracy, and NPV between core biopsies, FNAs, and combined core and FNA biopsies. Furthermore, no significant difference was found between head/neck and body/tail samplings. In 96.7% (85/88) of the cases, the procedure was uneventful. There were no major complications. CONCLUSIONS: Percutaneous US-guided sampling of pancreatic mass is safe and effective irrespective of location of the mass and method of biopsy.

Response Evaluation Criteria in Solid Tumors (RECIST) criteria are superior to European Association for Study of the Liver (EASL) criteria at 1 month follow-up for predicting long-term survival in patients treated with transarterial chemoembolization before liver transplantation for hepatocellular cancer.

PURPOSE: To determine whether response to transarterial chemoembolization can predict survival in patients with hepatocellular carcinoma (HCC) who are candidates for orthotopic liver transplantation (LT) and if either European Association for Study of the Liver (EASL) criteria or Response Evaluation Criteria in Solid Tumors (RECIST) criteria are more accurate for this purpose. MATERIALS AND METHODS: A retrospective review of all patients who underwent LT after transarterial chemoembolization between January 2005 and June 2011 was performed. Follow-up imaging with multiphasic computed tomography or magnetic resonance imaging was performed 1 month after transarterial chemoembolization and every 3 months thereafter until LT. Treatment response was evaluated at each imaging time point using RECIST criteria and EASL criteria. The relationship between survival and objective response (OR), time to response (TTR), time to progression (TTP), and time interval between transarterial chemoembolization and LT was assessed. RESULTS: A median of one transarterial chemoembolization procedure was performed before LT in 58 patients (52 men, 6 women; mean age, 57 y). OR was shown by 28 (48%) patients and 51 (88%) patients at 1 month by EASL criteria and RECIST criteria, respectively. OR at 1-month follow-up using RECIST criteria was associated with increased survival compared with patients with no response (NR) (P = .03). Using RECIST criteria, 5-year survival in the OR group was 66.7% versus 0% in the NR group (P = .015). There was no significant difference in survival in patients who showed OR at 1 month using EASL criteria. There was poor agreement between RECIST and EASL response assessments (κ = 0.23). There was no significant association between survival and TTR, TTP, or time interval between transarterial chemoembolization and LT. CONCLUSIONS: Patients with objective response to transarterial chemoembolization at 1 month using RECIST criteria showed improved survival over nonresponders. RECIST criteria demonstrated better accuracy compared with EASL criteria for predicting survival in patients after LT who had transarterial chemoembolization as a "bridge."

Prevalence and significance of extravascular incidental findings on computed tomographic angiography and magnetic resonance angiography.

Computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) are routinely used to evaluate patients with vascular disease. They have the ability to detect unexpected non-vascular pathology. The purpose of this study was to determine the prevalence and significance of extravascular incidental findings in patients undergoing CTA or MRA. A retrospective review of 737 patients who underwent CTA and 184 patients who underwent MRA during a five-year period was performed. Incidental findings were classified as low, moderate or high significance findings. For patients with high significance extravascular findings, assessment of the rates of appropriate follow-up was conducted. Among the CTA patients, 539 (73.1%) had incidental findings. Low, moderate and high significance findings were discovered in 514 (69.7%), 95 (12.9%) and 41 (5.6%) patients, respectively. Twenty (48.8%) patients with high significance findings received appropriate follow-up investigations. Among the MRA patients, 95 (51.6%) had extravascular findings. Low, moderate and high significance findings were present in 80 (43.5%), 27 (14.7%), and 3 (1.6%) patients, respectively. Two (66.7%) patients with high significance findings were properly followed up. In conclusion, incidental findings on CTA and MRA are very common. A small percentage of these findings could be serious and were not all adequately followed-up in our study population. Referring physicians should be aware of the potential for serious incidental findings and manage them appropriately.

Venous aneurysms in autogenous hemodialysis fistulas: is there an association with venous outflow stenosis.

PURPOSE: To determine whether patients with venous aneurysms in their arteriovenous fistulas (AVFs) have associated venous outflow stenoses. MATERIALS AND METHODS: A retrospective study was performed, which included all patients presenting with dysfunction and had venous aneurysms in their AVFs. Patient's medical records and imaging studies were examined and data collected including access characteristics, patient demographics and imaging findings. Data were analyzed using Fisher's exact test. RESULTS: A total of 89 patients (58 men, 31 women; mean age 60) presented for intervention related to access dysfunction with incident venous aneurysms over the study period. Of the 89 patients with venous aneurysms (mean diameter 2.3 cm) of their AVF's, 69 (78%) patients had an associated venous outflow stenosis. The stenoses were present most commonly in the outflow cephalic vein (57%), followed by the cephalic arch (20%), brachiocephalic vein (10%) and subclavian vein (6%). Outflow stenoses in AVFs with venous aneurysms were observed in 87% of brachiocephalic AVFs, 60% of radiocephalic AVFs and 80% of brachiobasilic AVFs. Brachiocephalic AVFs with venous aneurysms were significantly more likely to have an associated outflow stenosis than radiocephalic AVFs with venous aneurysms (P=0.007). AVFs with outflow stenosis were on average 1502 days old while AVFs without outflow stenosis were on average 2351 days old, which was a statistically significant difference (P=0.031). No statistically significant differences were observed for sex and side of the fistula. CONCLUSIONS: Outflow stenosis was observed to be associated with venous aneurysms in AVFs with a more statistically significant association in brachiocephalic AVFs compared to other AVFs.

An en bloc approach to CT perfusion for the evaluation of limb ischemia.

We examine volumetric CT perfusion in soft tissues of the entire foot with an en bloc technique to provide a meaningful measure of differentiation between mild and major vascular impairment. With Institutional Review Board approval, 22 healthy male subjects between the ages of 21 and 50 (mean 37) were enrolled. Volumetric computed tomography using an en bloc technique was conducted on 14 subjects for validation while unilateral vascular obstruction was simulated in the calves of the remaining 8 subjects. Perfusion estimates were made using in-house software and differences in perfusion estimates between feet were evaluated with Student's t-test at 95% confidence. Subjects with simulated major vascular obstruction (calf blood pressure cuff inflated to 200 mmHg) showed significantly higher ratios of perfusion estimates between the unobstructed and obstructed foot compared to subjects with simulated mild vascular obstruction (cuff inflated to 120 mmHg), mean 4.6, SD 2.6 vs. mean 1.3, SD 0.2; P = 0.05. CT perfusion using an en bloc technique shows promise for the future evaluation of patients with critical limb ischemia and particularly for re-characterization post medical, surgical or endovascular intervention.

Pathologic assessment of radiofrequency ablation of pulmonary metastases.

PURPOSE: To evaluate pathologically the effectiveness of radiofrequency (RF) ablation in the treatment of pulmonary metastases. MATERIALS AND METHODS: Patients with multiple pulmonary metastases scheduled for surgical resection were prospectively enrolled. Patients underwent RF ablation of one percutaneously accessible tumor and within 2-4 weeks underwent surgical resection of the ablated tumor and any additional lesions. Resected tumors all were assessed by routine light microscopy, and selected tumors were assessed by immunohistochemistry with MIB1 and proliferative cell nuclear antigen (PCNA). Relationship of ablation zone to the tumor and viability of the ablated tumors were assessed. RESULTS: Nine patients (four men and five women) 46-76 years of age were included in the study. Four patients had metastatic colorectal carcinoma, and five patients had metastases from soft tissue sarcomas. Ablated tumors ranged from 1.0-3.0 cm in diameter. Each target lesion was completely encompassed by the ablation zone. All tumor tissue within the ablation zone showed characteristic changes of coagulative necrosis with hematoxylin and eosin staining. Tumors showed preservation of MIB1 staining but loss of PCNA protein staining. RF ablation resulted in complete coagulative necrosis of all the pulmonary metastases treated in the study. CONCLUSIONS: Although this series is small, it provides histologic support for RF ablation as an effective treatment for selected pulmonary metastases.

Perfusion in peripheral musculoskeletal structures from dynamic volumetric computed tomography using an en bloc approach.

Volumetric computed tomography offers improved potential to perform perfusion analysis in peripheral musculoskeletal structures. Despite poor baseline tissue enhancement and artifacts from adjacent bone, reproducible perfusion estimates were attained using a volumetric en bloc technique in the plantar muscle compartment, Achilles tendon, and subcalcaneal adipose tissue of 16 feet in healthy male subjects. Inadequate enhancement prevented perfusion estimates in the second metatarsal head of all cases. Perfusion calculations succeeded in the calcaneus in 6 of the 16 examined feet.

The value of preprocedure computed tomography for planning insertion of inferior vena cava filters.

PURPOSE: To determine if valuable information could be obtained from abdominal computed tomography (CT) performed before insertion of an inferior vena cava (IVC) filter. MATERIALS AND METHODS: A retrospective review was performed on IVC filter insertions with a CT performed before the procedure. Cavagram and CT were compared for renal vein and IVC anatomy, the diameter of the IVC, and the prevalence of iliocaval thrombus. Correlations were assessed among 3 reference standards for measuring the IVC at cavography. RESULTS: The mean IVC diameter was 23.0 mm on CT. On cavagram the mean IVC diameter was assessed by using 3 reference standards: 20.7 mm, with the catheter tip as a reference; 26.9 mm, with a radiopaque ruler; and 23.4 mm, by using a lumbar vertebral body. There was good correlation among the 3 measures of IVC diameter (Pearson's r = 0.75, P < .0001) but moderate correlation with CT (r = 0.36-0.56, P < .001). The sensitivity of cavagram for detecting retroaortic and circumaortic renal veins was 40% and 0%, respectively. Nineteen accessory renal veins (12.8%) were not seen by cavagram. Thirteen patients (8.8%) had iliocaval thrombus on cavagram, of which 12 (92.3%) were not previously detected by CT. CONCLUSIONS: CT is more sensitive than cavagram for detection of renal vein variants and the level of the lowest renal vein. Therefore, if available, the CT should be reviewed before placement of an IVC filter to optimize positioning. Cavagram remains the criterion standard for detection of iliocaval thrombosis and is necessary before IVC filter insertion.