Non-enhanced MR angiography of renal arteries: comparison with contrast-enhanced MR angiography.

BACKGROUND: The main causes of renal artery stenosis (RAS) are atherosclerosis and fibromuscular dysplasia. Despite contrast-enhanced magnetic resonance angiography (CE-MRA) being a safe and reliable method for diagnosis of RAS especially in young individuals, recently it has been possible to adopt innovative technologies that do not require paramagnetic contrast agents. PURPOSE: To assess the accuracy of steady-state free-precession (SSFP) non-contrast-enhanced magnetic resonance angiography (NC-MRA) by using a 1.5 T MR scanner for the detection of renal artery stenosis, in comparison with breath-hold CE-MRA as the reference standard. MATERIAL AND METHODS: Sixty-three patients (33 men, 30 women) with suspected renovascular hypertension (RVHT) were examined by a 1.5T MR scanner; NC-MRA with an electrocardiography (ECG)-gated SSFP sequence was performed in 58.7% (37/63) of patients; in 41.3% (26/63) of patients a respiratory trigger was used in addition to cardiac gating. CE-MRA, with a three-dimensional gradient echo (3D-GRE) T1-weighted sequence, was performed in all patients within the same session. Maximum intensity projection (MIP) image quality, number of renal arteries, and the presence of stenosis were assessed by two observers (independently for NC-MRA and together for CE-MRA). The agreement between NC-MRA and CE-MRA as well as the inter-observer reproducibility were calculated with Bland-Altman plots. RESULTS: MIP image quality was considered better for NC-MRA. NC-MRA identified 143 of 144 (99.3%) arteries detected by CE-MRA (an accessory artery was not identified). Fourteen stenoses were detected by CE-MRA (11 atherosclerotic, 3 dysplastic) with four of 14 (28.5%) significant stenosis. Bland-Altman plot demonstrated an excellent concordance between NC-MRA and CE-MRA; particularly, the reader A evaluated correctly all investigated arteries, while over-estimation of two stenoses occurred for reader B. Regarding NC-MRA, inter-observer agreement was excellent. CONCLUSION: NC-MRA is a valid alternative to CE-MRA for the assessment of renal arteries.

Radiofrequency ablation for single lung tumours not suitable for surgery: seven years' experience.

PURPOSE: This study was done to review recurrence patterns in patients with lung cancer (primary or secondary) treated with percutaneous image-guided radiofrequency (RF) ablation. MATERIALS AND METHODS: From January 2003 to August 2010, 32 patients (24 with primary non-small-cell lung cancer and eight with metastases) with single lung cancer were treated with RF ablation. Post-treatment imaging results were available for each patient. Follow-up was performed using computed tomography (CT) scans at 1, 3, 6, 12, 18 and 24 months after the procedure and annually thereafter. Patterns of recurrence were classified as local, intrapulmonary, nodal, mixed and distant. We evaluated overall survival after RF ablation and the factors associated with recurrence. RESULTS: Seventeen (53.1%) patients showed no evidence of recurrence at follow-up imaging (range 12-72 months; mean, 32.5 months). Recurrence was seen in 15 (46.9 %) patients (range 6-36 months; mean 14.8 months). Local recurrence (40%) after RF ablation was the most frequent. Median disease-free survival was 20 months. Sex, tumour location, tumour size and tumour stage were not associated with a risk of recurrence. Patient age was related to the risk of recurrence (p<0.05). CONCLUSIONS: Local recurrence is the most common pattern in our series. A more aggressive initial RF ablation might offer improvement in outcomes, but this hypothesis needs to be confirmed by larger studies involving a larger number of patients.

Suprarenal inferior vena cava filter implantation.

PURPOSE: This study evaluated the feasibility, safety, and efficacy of the suprarenal implantation of a retrievable filter in patients with renal cell carcinoma (RCC) and renal vein thrombosis (RVT) [extending or not extending to the inferior vena cava (IVC)] undergoing surgery. MATERIALS AND METHODS: Between March 2005 and May 2010, 13 patients (eight men and five women; mean age 67.08 years, range 38-95) with RCC and RVT associated or not with IVC thrombosis underwent implantation of a retrievable suprarenal IVC filter. All patients underwent computed tomography angiography (CTA), which documented RVT and in some cases its extension to the IVC. The level of IVC involvement by the neoplastic thrombus was evaluated on the basis of the Oto classification. Cavography was performed before and after filter implantation. Surgical resection of RCC was performed in all patients. A CTA scan was performed 1 week before filter removal. RESULTS: The procedure had 100% feasibility. All filters were correctly deployed in the suprarenal tract of the IVC. There was no evidence of peri-or postprocedural complications. All patients were monitored for clinical symptoms of pulmonary embolism (PE). There was no evidence of PE in the 30 days after the procedure. All suprarenal IVC filters were removed from 30 to 60 days after surgery. CONCLUSIONS: Implantation of a temporary suprarenal IVC filter is an additional and feasible procedure that can prevent immediate and perioperative PE.

Initial experience with percutaneous biopsies of bone lesions using XperGuide cone-beam CT (CBCT): technical note.

PURPOSE: This paper describes our preliminary experience with percutaneous bone biopsy under XperGuide conebeam computed tomography (CBCT) guidance. MATERIALS AND METHODS: Seventeen patients (11 men and 6 women; mean age 57.8; range 17-81) with 17 bone lesions underwent biopsy with XperGuide CBCT (Philips Medical System, Best, The Netherlands). The mean diameter of the lesions was 2.32 cm (range 1-8 cm). Technical success (defined as the correct positioning of the needle within the lesion), diagnostic accuracy, sensitivity and specificity were evaluated. Complication rate was also recorded. RESULTS: The technical success rate was 100%. In 15 patients, a sample of adequate material for histopathological analysis to yield a definitive diagnosis was obtained; in two patients, the sample was inadequate for a definitive diagnosis. In one of these two cases, the lesion was closely followed up for 1 year, during which it remained stable in size, and as a result, it was considered a false positive; the other was considered a false negative. Diagnostic accuracy, sensitivity and specificity were 94.12%, 90.91% and 100%, respectively. No major complications were recorded; only one patient had slight bleeding, with a consequent small haematoma, which reabsorbed in about 15 days. CONCLUSIONS: Bone biopsy under XperGuide CBCT guidance can be considered accurate as a result of the combination of real-time needle orientation and spatial resolution of CT fluoroscopy. Moreover, our results are encouraging in terms of complication rate, diagnostic accuracy, sensitivity, specificity and reduction of CT workload.

Percutaneous cholecystostomy as the sole treatment in critically ill and elderly patients.

PURPOSE: This study was done to investigate the effectiveness and clinical outcome of percutaneous cholecystostomy (PC) of treating acute cholecystitis in critical ill and elderly patients. MATERIALS AND METHODS: In the last 3 years, PC was performed on 30 elderly and critically ill patients (17 men, 13 women; mean age 78.6, range 57-97 years) with acute cholecystitis and comorbid diseases. RESULTS: Technical success was 30/30 (100%). Clinical effectiveness was 30/30 (100%), with statistically significant reductions in while blood cell (WBC) count, C-reactive protein (CRP) and fever. Mean WBC upon admission (19.87×10(3)±1.61×10(3) /µl), axillary temperature (38.2±0.11 °C), and CRP (248.7±4.76 mg/l) values were significantly decreased in the 72 h following PC [12.9×10(3) ± 1.05×10(3)/µl (p≤0.0001), 37 ± 0.04 °C (p≤0.0001), 113.5 ± 3 mg/l (p≤0.0001), respectively]. Clinical and ultrasonographic (US) signs of acute cholecystitis decreased in all patients. There were no major complications or procedure-related deaths, and the morbidity rate was low (3/30; 10%). CONCLUSIONS: PC appears to be a fast, easy and effective treatment for the acute phase of cholecystitis in elderly and critically ill patients. Procedure-related morbidity and mortality rates are very low compared with surgery. Conservative treatment for patients who are not eligible for surgery is acceptable.

Upper urinary tract biopsy: an old device for a new approach.

PURPOSE: The authors sought to evaluate the feasibility, diagnostic accuracy and safety of urological biopsy performed using a flexible alligator forceps. MATERIALS AND METHODS: Twenty-seven patients with suspected urothelial malignancy underwent retrograde biopsy using a 7-F biopsy forceps (Cordis, Miami, FL, USA). Mild sedation was guaranteed by an anaesthesiologist. The final diagnosis was confirmed by cytohistological data and subsequently by pathology findings at surgery. Lesions with benign histopathology were closely monitored for at least 12 months. RESULTS: The technical success rate was 92.6%. The high diagnostic accuracy was related to the positive correspondence between histological outcomes and surgical results or follow-up observations. As regards sample site, the procedure was less successful in calyceal lesions than in lesions located in the upper urinary tract, with a technical success of 71.43%. Twenty patients had asymptomatic haematuria in the early hours after the procedure; ten of them had mild dysuria. No one require medication, and no major complications occurred. CONCLUSIONS: Urological forceps biopsy is a safe and easy procedure. It provides a relatively high level of accuracy in the diagnosis of lesions of the upper urinary tract.

Endovascular treatment of ruptured abdominal aortic aneurysms: aorto-uni-iliac or bifurcated endograft?

PURPOSE: This study evaluated the safety and technical and clinical success rates of positioning endovascular endografts (EG) in ruptured abdominal aneurysms. MATERIALS AND METHODS: Patients with a ruptured abdominal aortic aneurysm confirmed by contrast-enhanced computed tomography angiography (CTA) were eligible for the analysis. Of 67 patients, 42 (62.7%) were treated with EG. Thirteen patients (30.9%) received an aorto-uni-iliac EG (group A) and 29 a bifurcated EG (group B). Patients were divided for comparative analysis according to the configuration of the EG implanted. RESULTS: The primary technical success rate was 100%; the primary clinical success rate was 95% (40/42). There were two intraoperative deaths (4.7%) related to intractable shock. No patient required conversion to open repair. Overall, 12 patients (28.5%) died within 30 days. The in-hospital death rate was 30.9% (13/42). Hospital mortality rate was statistically higher in group A; the type of EG and intensive care unit admission were the only independent predictors of hospital mortality. CONCLUSIONS: In our experience, a higher mortality rate was observed for the aorto-uni-iliac configuration; shock at admission was confirmed as the most important factor for postoperative survival.

Complications of microwave and radiofrequency lung ablation: personal experience and review of the literature.

PURPOSE: Complications correlated with percutaneous radiofrequency ablation (RFA) and microwave ablation (MWA) of lung tumours were retrospectively reviewed to compare them with data from the literature and to assess risk factors related with the procedures. MATERIALS AND METHODS: From January 2003 to January 2009, 29 patients (36 lung lesions) were treated with RFA; from January 2007 to January 2009, 16 patients (17 lung lesions) were treated with MWA. Complications recorded at our institution are reported following the Society of Interventional Radiology guidelines. A systematic review of the literature was performed. RESULTS: Any major complication of RFA or MWA was recorded. In agreement with the literature, pneumothorax was the most frequent complication, even though the incidence in our series was lower than reported in the literature (3.5% vs. 4.3-18%). Other complications of RFA were pleural effusion and subcutaneous emphysema. No massive haemorrhages, haemoptysis, abscesses, pneumonia, infections or tumour seeding were recorded in our series. The most common complication of MWA was pneumothorax (25% vs. 39% reported in the literature). Pleural effusion was a common reaction, but therapeutic drainage was never required. CONCLUSIONS: Pneumothorax is the most common complication of both techniques. RFA and MWA are both excellent choices in terms of safety and tolerance.