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.

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.

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.

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.

Needle tract seeding after radiofrequency ablation of hepatic tumors.

PURPOSE: To determine the incidence and risk factors associated with needle tract seeding after radiofrequency ablation (RFA) of liver tumors. MATERIALS AND METHODS: A prospective data base of patients with hepatic tumors treated by RFA from December 1999 until August 2003 was reviewed to identify patients with needle tract seeding. During this period, 200 patients (148 men, 52 women) with 299 lesions underwent 298 treatment sessions. Patients with both primary (153 hepatocellular carcinoma, two cholangiocarcinoma) and a variety of secondary tumors (35 colorectal, 10 other) were treated. RFA was performed percutaneously with computed tomography (CT) and/or ultrasound (US) guidance, or with US guidance at laparoscopy or laparotomy. All procedures were performed with a LeVeen needle electrode. The needle tract was not routinely coagulated or embolized. RESULTS: Eight patients out of 200 (4%) were identified with needle tract seeding, based on imaging findings or surgical reintervention. This corresponds to a rate of eight of 298 (2.7%) per treatment session and eight of 299 (2.7%) per lesion. Statistically significant risk factors for neoplastic seeding included treatment of a subcapsular lesion (OR = 11.57, P = .007), multiple treatment sessions (OR = 2.0, P = .037), and multiple electrode placements (OR = 1.4, P = .006). CONCLUSIONS: Neoplastic seeding may occur after RFA of liver tumors. The results show that the frequency of this complication is not insignificant, and are at the upper end of rates reported in the literature of 0.5% to 2.8%. Specific risk factors identified in this study include treatment of subcapsular lesions, patients treated in multiple sessions, and lesions requiring more than one electrode placement.