Biomedical subjects

Claudio Vignali

Publications and source records attributed to Claudio Vignali.

10 recordsLinked to original sources

PubMed2005

Type II lumbar endoleaks: hemodynamic differentiation by contrast-enhanced ultrasound scanning and influence on aneurysm enlargement after endovascular aneurysm repair.

OBJECTIVE: The objective of this study was to differentiate type II lumbar endoleaks on the basis of dynamic features identified by contrast-enhanced ultrasound scanning (CUS) and to evaluate the role of this differentiation in detecting abdominal aortic aneurysm (AAA) enlargement > or =1 mL/mo. METHODS: Eighteen male patients (mean age, 71.8 years) with type II lumbar endoleak suspected at CUS underwent computed tomography angiography (CTA) and digital subtraction angiography (DSA). On CTA, AAA volumes and endoleak visualization and volume were assessed. At CUS, performed after a bolus of 1.5 to 2.4 mL of a second generation blood pool contrast agent, the following parameters were evaluated: presence of contrast material within the aneurysmal sac (endoleak), delay of endoleak detection (wash-in) and disappearance (washout) from the beginning of contrast injection, visualization of inflow and outflow vessels, and presence of cavity filling. Statistical analysis was performed regarding endoleak features at CUS, endoleak detection at CTA, and rate of AAA enlargement. RESULTS: DSA confirmed all the endoleaks. Mean +/- standard deviation wash-in and washout times were 121.9 +/- 132.6 and 337.2 +/- 193.7 seconds, respectively; a significant relation was observed between these two parameters (P < .01, analysis of variance). By Youden plots, endoleaks were classified as hyperdynamic when wash-in was <100 seconds (n = 10, 55.5%) and/or washout was <520 seconds (n = 13, 72.2%). A slower washout was associated with nonvisualized outflow (66.7%) and/or inflow arteries (66.7%) ( P < .05). Eight endoleaks (44.4%) were missed at CTA; it occurred in hypodynamic endoleaks, absence of detectable inflow or outflow vessels, and absence of cavity filling at CUS (P < .05). Overall mean AAA volume increase rate was 1.1 +/- 1.7 mL/mo. By multiple logistic regression model, the washout time > or = 520 seconds was the only independent predictor of AAA volume increase > or = 1 mL/mo (8 patients, 44.4%). CONCLUSION: Type II lumbar endoleaks show different hemodynamic features at CUS, which might influence the rate of aneurysm enlargement, addressing the need for treatment.

Aged↗

PubMed2005

Low-profile stent system for treatment of atherosclerotic renal artery stenosis: the GREAT trial.

PURPOSE: The Palmaz Genesis Peripheral Stainless Steel Balloon Expandable Stent in Renal Artery Treatment (GREAT) Trial was designed to assess the safety and performance of a low-profile stent for the treatment of obstructive renal artery disease by looking at 6-month renal artery patency uniformly analyzed by a Core Lab. MATERIALS AND METHODS: Fifty-two consecutive patients (mean age, 63.7 years) were successfully treated with the Palmaz Genesis Peripheral Stent (Cordis, Miami, FL) on the Slalom 0.018-inch Delivery System (Cordis Europe N.V., Oosteinde 8, NLO-9301 LJ Roden, The Netherlands) at 11 investigational centers. Patients with severe renal failure and > 8-mm renal artery were excluded. Primary endpoint was angiographic determination of in-stent percent diameter stenosis at 6 months. Fifty-one patients were treated with one stent, one patient was treated with two stents to cover the complete lesion. RESULTS: Mean percentage diameter stenosis before renal angioplasty was 68.2% +/- 12.0%. No stent implantation failure, displacement, need for additional stent implantation, or procedural complication was observed. Six-month angiography was performed in 41 of 52 patients (79%) resulting in a mean in-stent percent diameter stenosis or Quantitative Vessel analysis (QVA) at 6 months of 23.9%. The in-stent binary (percent diameter stenosis > 50%) restenosis rate at 6 months was 14.3%. No fatal events occurred up to 6 months after implantation. Major adverse events occurred in five patients: four patients (7.7%) required a revascularization and one patient (1.9%) experienced a cerebrovascular event, which regressed spontaneously. CONCLUSIONS: The Palmaz Genesis stent (Cordis) provides good results for renal artery stent placement, with an in-stent binary restenosis rate (percent diameter stenosis > 50%) at 6 months of 14.3% as determined with angiography.

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PubMed2005

TIPS with expanded polytetrafluoroethylene-covered stent: results of an Italian multicenter study.

OBJECTIVE: Our objective is to describe the results of a multicenter prospective trial on the safety and efficacy of transjugular intrahepatic portosystemic shunts (TIPS) using the Viatorr stent-graft. SUBJECTS AND METHODS: From 2001 to 2003, 114 patients (75 men and 39 women; mean age, 59.3 years) with portal hypertension underwent TIPS with the Viatorr stent-graft. Indications for treatment were variceal bleeding (n = 49, 43.0%), refractory ascites (n = 52, 45.6%), hypertensive gastropathy (n = 10, 8.8%), Budd-Chiari syndrome (n = 1, 0.9%), and hepatorenal syndrome (n = 2, 1.7%). Eight patients (7.0%) had Child-Pugh class A cirrhosis; 60 (52.6%), Child-Pugh class B; and 46 (40.4%), Child-Pugh class C. Patients were monitored by color Doppler sonography and phlebography. RESULTS: The procedure was successful in 113 (99.1%) of 114 patients; in one patient, creation of the track was not feasible. The mean portosystemic pressure gradient decreased from 21.8 to 8.7 mm Hg. Three minor immediate complications (2.6%) occurred (two cases of self-limiting hemoperitoneum and one extrahepatic portal puncture requiring covered stenting). At a mean follow-up of 11.9 months, the overall mortality rate was 31.0% (35/113), with a 30-day mortality rate of 8.8% (10/113). Mortality was significantly higher in patients in Child-Pugh class C with refractory ascites and with post-procedural encephalopathy. Cumulative primary patency rates were 91.9%, 79.9%, and 75.9% at 6, 12, and 24 months' follow-up, respectively. Restenosis occurred in 15 patients (13.3%) within the stent (n = 8, 53.3%) or at the ends of the portal (n = 1, 6.7%) or hepatic (n = 6, 40%) veins and was solved by percutaneous transluminal angioplasty (n = 11), stenting (n = 3), or parallel TIPS (n = 1). The secondary patency rate was 98.2%. Post-procedural encephalopathy occurred in 27 patients (23.9%). CONCLUSION: The Viatorr stent-graft is safe and effective in TIPS creation, with high primary patency rates. Covering the entire track up to the inferior vena cava can increase patency.

Adolescent↗

PubMed2004

Abdominal aortic aneurysms: virtual imaging and analysis through a remote web server.

The study describes the application of a web-based software in the planning of the endovascular treatment of abdominal aortic aneurysms (AAA). The software has been developed in the framework of a 2-year research project called Aneurysm QUAntification Through an Internet Collaborative System (AQUATICS); it allows to manage remotely Virtual Reality Modeling Language (VRML) models of the abdominal aorta, derived from multirow computed tomography angiography (CTA) data sets, and to obtain measurements of diameters, angles and centerline lengths. To test the reliability of measurements, two radiologists performed a detailed analysis of multiple 3D models generated from a synthetic phantom, mimicking an AAA. The system was tested on 30 patients with AAA; CTA data sets were mailed and the time required for segmentation and measurement were collected for each case. The Bland-Altman plot analysis showed that the mean intra- and inter-observer differences in measures on phantoms were clinically acceptable. The mean time required for segmentation was 1 h (range 45-120 min). The mean time required for measurements on the web was 7 min (range 4-11 min). The AQUATICS web server may provide a rapid, standardized and accurate tool for the evaluation of AAA prior to the endovascular treatment.

Angiography↗

PubMed2004

Abdominal aortic aneurysm: contrast-enhanced US for missed endoleaks after endoluminal repair.

PURPOSE: To evaluate contrast material-enhanced ultrasonography (US) for depiction of endoleaks after endovascular abdominal aortic aneurysm repair (or endovascular aneurysm repair [EVAR]) in patients with aneurysm enlargement and no evidence of endoleak. MATERIALS AND METHODS: From November 1998 to February 2003, 112 patients underwent EVAR. At follow-up, duplex US and biphasic multi-detector row computed tomographic (CT) angiography were performed. In 10 patients (group A), evident aneurysm enlargement was observed, with no evidence of complications, at both CT angiography and duplex US. Group A patients, 10 men (mean age, 69.6 years +/- 10 [standard deviation]), underwent US after intravenous bolus injection of a second-generation contrast agent, with continuous low-mechanical index (0.01-0.04) real-time tissue harmonic imaging. Group B patients, 10 men (mean age, 71.3 years +/- 8.2) with aneurysm shrinkage and no evidence of complications, and group C patients, 10 men (mean age, 73.2 years +/- 6) with CT angiographic evidence of endoleak, underwent contrast-enhanced US. Digital subtraction angiography (DSA) was performed in groups A and C. Endoleak detection and characterization were assessed with imaging modalities used in groups A-C; at contrast-enhanced US, time of detection of endoleak, persistence of sac enhancement, and morphology of enhancement were evaluated. RESULTS: In group A, contrast-enhanced US depicted one type I, six type II, one type III, and two undefined endoleaks that were not detected at CT angiography. All leakages were characterized by slow and delayed echo enhancement detected at longer than 150 seconds after contrast agent administration. DSA results confirmed findings in all patients; percutaneous treatment was performed. In group B, contrast-enhanced US did not show echo enhancement; in group C, results with this modality confirmed findings at CT angiography and DSA. CONCLUSION: Contrast-enhanced US depicts endoleaks after EVAR, particularly when depiction fails with other imaging modalities.

Aged↗

PubMed2003

Vascular injuries after percutaneous renal procedures: treatment by transcatheter embolization.

Percutaneous renal procedures have become the standard technique for diagnosis and treatment of a number of renal pathologies. Hemorrhage and vascular lesions are the most serious complications. We report our experience with 15 patients treated by hyperselective vascular embolization. Fifteen patients (10 men and 5 women; mean age 55 years) had severe perioperative hemorrhage after percutaneous renal procedures, due to arterial renal major injury. All patients underwent duplex US, CT, and renal arteriography demonstrating the presence of arteriovenous fistulas (n=2), renal hematoma (n=3), pseudoaneurysms (n=3), and hematoma with pseudoaneurysm (n=7). Four patients showed transient renal dysfunction, with an increase in serum creatinine levels. One patient had a solitary transplanted kidney. Hyperselective arterial embolization was performed successfully by means of coils (n=14), associated with gelfoam in 4 cases; homologous blood clot was used in 1 patient. No major complications occurred, and renal function rapidly normalized in the 4 patients with transient renal failure. Imaging follow-up confirmed the successful devascularization of the lesion. Renal arterial hemorrhage following percutaneous procedures is a rare but severe complication. Hyperselective renal artery embolization, with particles and/or coils, represents the first-choice treatment option, being safe and effective in stopping the bleeding.

Angiography, Digital Subtraction↗

PubMed2003

Evaluation of the proximal aortic neck enlargement following endovascular repair of abdominal aortic aneurysm: 3-years experience.

The aim of this study was to evaluate incidence, potential risk factors and effects on stent-graft migration of proximal neck dilatation after endoluminal repair of abdominal aortic aneurysm (EVAR), and the role of ultrasound (US) in detecting neck enlargement. From November 1998 to October 2001, 90 patients underwent EVAR. On follow-up, US and CT angiography (CTA) were performed, and diameters of the suprarenal and infrarenal aortic necks were monitored. Incidence of significant neck enlargement (> or =2.5 mm) and distal stent-graft migration (>10 mm) was calculated. Several factors were evaluated as predictive of neck enlargement. Ultrasound and CTA measurements were compared. The US and CTA examinations were available in 68, 39, and 11 patients at 1, 2, and 3 years follow-up (mean follow-up 15 months). Incidence of significant neck dilatation was 21.8% at the infrarenal level (13, 33, and 36% at 1, 2, and 3 years follow-up) and 13.8% at the suprarenal level (9, 18, and 27% at 1, 2, and 3 years follow-up). Significant stent-graft migration occurred in 14 of 87 patients (16%) and was associated with neck dilatation in 8 (2 suprarenal and 6 infrarenal). No risk factors were identified. Ultrasound was less accurate than CT in measuring neck diameter, in particular at the suprarenal level. Proximal aortic neck enlargement occurs in up to 30% of patients after EVAR and represents the main risk factor for stent-graft migration. The risk of infrarenal neck dilatation is higher at 2 years follow-up, whereas the suprarenal neck enlarges later. Ultrasound is not useful in monitoring neck diameter.

Aged↗

PubMed2002

T-tube removal after liver transplantation: a new technique that reduces biliary complications.

This article discusses a new simple, fast, and easily performed technique that allows reduction of morbidity and hospital stay after T-tube removal. A retrospective analysis was conducted of 145 recipients who underwent T-tube removal 3 months after orthotopic liver transplantation. Patients were divided in two groups: group 1 (n=93) underwent T-tube removal and contemporary placement under fluoroscopic guidance of a counter-drain. Group 2 (n=52) T-tubes were removed from the bile duct under fluoroscopy but were left in place as a counter-drain. Overall, there were 33 (22.7%) complications related to T-tube removal. Treatment was always conservative and no deaths were related to T-tube. In group 1, 29 (31.2%) complications occurred; and the mean hospital stay was 9.4+/-9.3 days. In group 2, four complications (7.7%) occurred (P=0.002); and the mean hospital stay was 5.8+/-5.5 days (P=0.012). The adoption of this new technique-under fluoroscopic guidance, using the T-tube itself as a counter-drain-for T-tube removal allowed us to significantly reduce biliary complications and hospital stay.

Biliary Tract Diseases↗

PubMedDate not supplied

Predictive factors of in-stent restenosis in renal artery stenting: a retrospective analysis.

PURPOSE: To retrospectively evaluate the role of clinical and procedural factors in predicting in-stent restenosis in patients with renovascular disease treated by renal artery stenting. METHODS: From 1995 to 2002, 147 patients underwent renal artery stenting for the treatment of significant ostial atherosclerotic stenosis. Patients underwent strict clinical and color-coded duplex ultrasound follow-up. Ninety-nine patients (111 stents), with over 6 months of continuous follow-up (mean 22+/-12 months, range 6-60 months), were selected and classified according to the presence (group A, 30 patients, 32 lesions) or absence (group B, 69 patients, 79 lesions) of significant in-stent restenosis. A statistical analysis was performed to identify possible preprocedural and procedural predictors of restenosis considering the following data: sex, age, smoking habit, diabetes mellitus, hypertension, serum creatinine, cholesterol and triglyceride levels, renal artery stenosis grade, and stent type, length and diameter. RESULTS: Comparing group A and B patients (chi(2) test), a statistically significant relation was demonstrated between stent diameter and length and restenosis: the risk of in-stent restenosis decreased when the stent was >/=6 mm in diameter and between 15 and 20 mm in length. This finding was confirmed by multiple logistic regression analysis. Stent diameter and length were proved to be significantly related to in-stent restenosis also when evaluating only patients treated by Palmaz stent (71 stents). CONCLUSION: Although it is based on a retrospective analysis, the present study confirms the importance of correct stent selection in increasing long-term patency, using stents of at least 6 mm in diameter and with a length of approximately 15-20 mm.

Adult↗

PubMedDate not supplied

Endovascular repair of abdominal aortic aneurysms: analysis of aneurysm volumetric changes at mid-term follow-up.

PURPOSE: To evaluate the volumetric changes in abdominal aortic aneurysms (AAA) after endovascular AAA repair (EVAR) in 24 months of follow-up. METHODS: We evaluated the volume modifications in 63 consecutive patients after EVAR. All patients underwent strict duplex ultrasound and computed tomography angiography (CTA) follow-up; when complications were suspected, digital subtraction angiography was also performed. CTA datasets at 1, 6, 12, and 24 months were post-processed through semiautomatic segmentation, to isolate the aneurysmal sac and calculate its volume. Maximum transverse diameters (Dmax) were also obtained in the true axial plane, Presence and type of endoleak (EL) were recorded. A statistical analysis was performed to assess the degree of volume change, correlation with diameter modifications, and significance of the volume increase with respect to ELs. RESULTS: Mean reconstruction time was 7 min. Mean volume reduction rates were 6.5%, 8%, and 9.6% at 6, 12, and 24 months follow-up, respectively. Mean Dmax reduction rates were 4.2%, 6.7%, and 12%; correlation with volumes was poor (r = 0.73-0.81). ELs were found in 19 patients and were more frequent (p = 0.04) in patients with higher preprocedural Dmax, The accuracies of volume changes in predicting ELs ranged between 74.6% and 84.1% and were higher than those of Dmax modifications. The strongest independent predictor of EL was a volume change at 6 months < or = 0.3% (p = 0.005), although 6 of 19 (32%) patients with EL showed no significant AAA enlargement, whereas in 6 of 44 (14%) patients without EL the aneurysm enlarged. CONCLUSION: The lack of volume decrease in the aneurysm of at least 0.3% at 6 months follow-up indicates the need for closer surveillance, and has a higher predictive accuracy for an endoleak than Dmax.

Aged↗