RESUMEN

PURPOSE: Accurate stenosis quantification in the carotid arteries is of great clinical importance. We aimed to compare the diagnostic accuracy of multi-slice computed tomography angiography (CTA) to digital subtraction angiography (DSA) for the detection and grading of atherosclerotic lesions involving the supraaortic arteries. MATERIALS AND METHODS: We retrospectively analyzed 30 patients (10 women; mean age, 67 years). CTA was performed after administration of 100 ml Ultravist 370 (Bayer Schering, Germany), at a flow of 5 ml/s, using a Philips Brilliance 16MDCT scanner (Philips, Best, Netherland) at a collimation of 16 mm×0.75 mm prior to DSA. The supraaortic arteries were divided into 17 segments, and, within each segment, the presence and severity of stenotic or occlusive lesions was determined, based on a four-point scale (0-49%, 50-69%, 70-99%, occlusion), by four independent readers using the NASCET criteria. Sensitivity and specificity of MDCT was calculated for the detection of moderate (50-69%) versus significant stenoses (70-99%) and occlusion. RESULTS: There were 291 segments assessed with both methods. Thirteen lesions were "not assessable" on CTA. DSA identified 53 significant lesions, and CTA 56 significant lesions. With regard to significant lesions, CTA overrated six lesions and underestimated six lesions, resulting in a sensitivity, specificity, and accuracy of 86.4%, 97.6%, and 95.9%, respectively. For the detection of stenoses greater than 50%, sensitivity, specificity, and accuracy were 90.2%, 95.8%, and 94.8%, respectively. CONCLUSIONS: Compared to DSA, CTA shows high accuracy in the detection and grading of lesions involving the supraaortic arteries enabling its use in the detection and treatment planning for stenoses of the supraaortic vessels.

Asunto(s)

Angiografía de Substracción Digital/métodos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Aortografía/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad

RESUMEN

PURPOSE: To determine the primary success and short-term patency of stent application as a primary treatment modality for high-grade lesions of the infrapopliteal arteries compared with treatment with percutaneous transluminal angioplasty (PTA) in critical limb ischemia in a randomized prospective study. METHODS: Endovascular therapy was performed on 95 lesions in 51 patients (mean age 72.0 years, range 47-80 years) who presented clinically with Fontaine stages III and IV. One patient underwent treatment in both limbs. After angiographic lesion identification, patients were randomized for treatment by PTA (53 lesions in 27 patients) or stent application (42 lesions in 24 patients). Follow-up by clinical investigation and conventional angiography or spiral CT angiography was performed in 37 patients (57 lesions) 6 to 12 months after the procedure, or when clinically indicated. Evaluation was performed by two observers, double-blinded, with thresholds for lesion restenosis of 50% and 70%. Statistical evaluation was performed on a lesion basis by Kaplan-Meier estimated probability rates, and log-rank and Wilcoxon tests. The primary endpoint was the angiographic patency rate of treated lesions. RESULTS: The inter-reader agreement was high (kappa = 0.82). For the stent group the cumulative primary patency at 6 months was 83.7% at the 70% restenosis threshold, and 79.7% at the 50% restenosis threshold. For PTA, the primary patency at 6 months was 61.1% at the 70% restenosis threshold and 45.6% at the 50% restenosis threshold. Both results were statistically significant (p < 0.05). CONCLUSION: Infrapopliteal stent application is an effective treatment modality for high-grade lesions in chronic critical limb ischemia. Compared with PTA, higher patency rates can be expected after 6 months.

Asunto(s)

Angioplastia de Balón , Isquemia/cirugía , Pierna/irrigación sanguínea , Arteria Poplítea/cirugía , Stents , Anciano , Anciano de 80 o más Años , Carbono , Materiales Biocompatibles Revestidos , Método Doble Ciego , Femenino , Humanos , Isquemia/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Proyectos Piloto , Arteria Poplítea/diagnóstico por imagen , Estudios Prospectivos , Radiografía , Estadísticas no Paramétricas , Análisis de Supervivencia , Resultado del Tratamiento , Grado de Desobstrucción Vascular

RESUMEN

Endovascular stent-graft placement has become a safe and effective treatment modality for various diseases of the distal aortic arch as well as of the descending aorta. However, its effectiveness may be limited by various kinds of endoleaks resulting in persistent or recurrent perfusion of the aneurysm sac. Subsequently, systemic pressurization leads to expansion of the aneurysm sac, exposing the patient to a recurrent risk of aneurysm rupture. We report on the case of a 57-year-old male who underwent emergency stent-graft placement in March 2001 due to a contained rupture of a distal aortic arch aneurysm involving the origin of the left subclavian artery. Due to the emergency condition, a subclavian-to-carotid artery transposition had not been performed prior to stent-graft placement. During follow-up the patient developed a type II endoleak originating from the left subclavian artery with consecutive enlargement of the aneurysm sac. The endoleak was successfully treated by subclavian-to-carotid artery transposition.

Asunto(s)

Aneurisma de la Aorta Torácica/cirugía , Rotura de la Aorta/cirugía , Arteria Carótida Común/trasplante , Stents , Arteria Subclavia/trasplante , Aneurisma de la Aorta Torácica/clasificación , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Rotura de la Aorta/clasificación , Rotura de la Aorta/diagnóstico por imagen , Implantación de Prótesis Vascular , Arteria Carótida Común/diagnóstico por imagen , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/trasplante , Humanos , Masculino , Persona de Mediana Edad , Arteria Subclavia/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento

RESUMEN

PURPOSE: To evaluate whether stent placement is superior to percutaneous transluminal angioplasty (PTA) in the treatment of chronic symptoms in short femoropopliteal arterial stenoses. MATERIALS AND METHODS: One hundred twenty-four limbs in 116 patients, who ranged in age from 39 to 87 years (mean age, 67 years), were randomized to PTA (n = 53) versus PTA followed by implantation of long-medium Palmaz-Stents (n = 71). Inclusion criteria were intermittent claudication or chronic critical limb ischemia, short stenosis or occlusion (lesion length < or = 5 cm), and at least one patent run-off vessel at angiography. The follow-up included clinical assessment, measurement of ankle/brachial index (ABI), color duplex ultrasound, and/or angiography at 6, 12 and 24 months. Angiographic follow-up between 12 and 36 months was available in 54 limbs (45 %). RESULTS: Initial technical success was achieved in 50 of 53 limbs (94.4 %) in the PTA group versus 70 of 71 limbs (98.6 %) in the stent group. Overall, major complications occurred in 9.5 % (n = 11), with n = 4 in the PTA group compared to n = 7 in the stent group. No difference was found between the groups of treatment: clinical success at 1 and 2 years was 80.5 and 77.1 % in the PTA group versus 78.1 and 71.0 % in the stent group. The cumulative 1-year and 2-year angiographic primary patency rates were 66.1 and 49.1 % in the stent group versus 76.1 and 66.1 % in the PTA group. The secondary 1-year and 2-year angiographic patency rates were 88.5 and 53.3 % in the stent group versus 82.7 % and 76.2 % in the PTA group. CONCLUSION: The primary success rate was slightly higher after stent placement than after PTA. However, the angiographic, clinical and hemodynamic success after 1 and 2 years tends to be slightly better for PTA.

Asunto(s)

Angioplastia de Balón , Arteriopatías Oclusivas/terapia , Arteria Femoral , Arteria Poplítea , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Angioplastia de Balón/efectos adversos , Interpretación Estadística de Datos , Femenino , Arteria Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Estudios Prospectivos , Stents/efectos adversos , Factores de Tiempo , Ultrasonografía Doppler en Color , Grado de Desobstrucción Vascular

RESUMEN

Vertebroplasty is a radiological intervention for the augmentation of bone lesions with bone cement. Main indications are the treatment of osteoporotic vertebral body fractures, however also the treatment of tumorous lesions becomes more and more established. The indication for vertebroplasty of tumorous lesions is therapy-refractory pain in symptomatic hemangiomas, metastases and myelomas. By minimal invasive therapy stabilization of vertebral bodies and pain reduction may be achieved.

Asunto(s)

Cifosis/cirugía , Procedimientos Ortopédicos/métodos , Osteoporosis/complicaciones , Fracturas de la Columna Vertebral/cirugía , Neoplasias de la Columna Vertebral/complicaciones , Vértebras Torácicas/cirugía , Tomografía Computarizada por Rayos X , Cementos para Huesos , Contraindicaciones , Fluoroscopía , Estudios de Seguimiento , Hemangioma/complicaciones , Humanos , Cifosis/etiología , Procedimientos Ortopédicos/efectos adversos , Dolor/tratamiento farmacológico , Dolor/etiología , Dolor/prevención & control , Plasmacitoma/complicaciones , Factores de Riesgo , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/etiología , Neoplasias de la Columna Vertebral/secundario , Vértebras Torácicas/lesiones , Factores de Tiempo , Resultado del Tratamiento

RESUMEN

BACKGROUND: In patients undergoing transjugular intrahepatic portosystemic shunt (TIPS), prognostic scores may identify those with a poor prognosis or even those with a clear survival benefit. The Child-Pugh score (CPS) is well established but several drawbacks have led to development of the model of end stage liver disease (MELD). AIM: The aim of the study was to compare the predictive power of CPS and MELD, to validate the original MELD formula, and to assess the predictive value of the determinants used in the two prognostic scores outside of a study setting. PATIENTS: A total of 501 patients underwent elective TIPS placement and 475 patients fulfilled the inclusion criteria. METHODS: Data of all patients undergoing elective TIPS in one university hospital and four community hospitals in Vienna, Austria, between 1991 and 2001, were analysed retrospectively. The main statistical tests were Cox proportional hazards regression model, the log rank test, Kaplan-Meier analysis, and concordance c statistics. RESULTS: Median follow up was 5.2 years and median survival was 4.6 years. During follow up, 230 patients died, 75 within three months after TIPS placement. In stepwise proportional hazards analyses, independent predictors of death were creatinine level, bilirubin level, age, and refractory ascites. MELD was better in predicting survival in a stepwise Cox model but both scores were equally predictive in c statistics for one month, three month, and one year survival. Renal function was the strongest independent predictor of survival. CONCLUSIONS: Although MELD was the primary predictor of overall survival in multivariate analysis, c statistics showed that both scores can be used for patients undergoing TIPS with equal accuracy. For assessing prognosis in patients undergoing TIPS implantation, there seems little reason to replace the well established Child-Pugh score.

Asunto(s)

Indicadores de Salud , Derivación Portosistémica Intrahepática Transyugular , Adulto , Anciano , Femenino , Estudios de Seguimiento , Hepatitis Viral Humana/cirugía , Humanos , Cirrosis Hepática Alcohólica/cirugía , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento

RESUMEN

PURPOSE: To investigate initial and long-term success rate after percutaneous treatment of iliac artery occlusion with angioplasty and stent deployment. To investigate the influence of vascular comorbidity, lesion length, stent placement and lesion coverage as possible predictors of outcome. METHODS: Between January 1994 and December 1999, 80 iliac recanalizations were performed on 78 patients, median age 61.1 +/- 11.5 (SD) years. All patients were followed up by clinical examinations, duplex ultrasound and intravenous digital subtraction angiography. Mean follow-up time was 2.0 +/- 1.53 (SD) years. Multivariate Cox regression analysis was used to determine the influence of cofactors on patency. RESULTS: One, 2 and 4 years after recanalization, primary patency was 78.1%, 74.5% and 64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively. Patients with shorter occlusions, complete lesion coverage and patent ipsilateral femoral arteries had significantly longer patency rates. Complications included inguinal hematoma (n=1), technical failure (n=3) aortic dissection (n=1), embolic occlusions (n=7), gluteal claudication (n=1) and genital necrosis after subsequent urethral surgery in one patient with contralateral occlusion and ipsilateral overstenting of the internal iliac artery with subsequent stenosis. Complications were of permanent clinical significance in seven of 78 (9%) of the patients. In 17 (22%) cases, percutaneous reintervention was performed with angioplasty in the stent (n=16) or deployment of a new stent (n=1). CONCLUSION: Endoluminal stent placement has its place in an interdisciplinary therapeutic approach as a viable therapeutic alternative to major transabdominal bypass surgery and can be performed with comparable complication rates. Patients with short occlusions, patent femoral arteries, and stents covering the entire occlusion have significant longer patency.

Asunto(s)

Angioplastia de Balón , Arteriopatías Oclusivas/terapia , Arteria Ilíaca , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/métodos , Arteriopatías Oclusivas/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Radiografía , Stents/efectos adversos , Factores de Tiempo , Resultado del Tratamiento

RESUMEN

The aim of this study was firstly to describe the spectrum of imaging findings seen in iliopsoas bursitis, and secondly to compare cross-sectional imaging techniques in the demonstration of the extent, size and appearance of the iliopsoas bursitis as referenced by surgery. Imaging studies of 18 patients (13 women, 5 men; mean age 53 years) with surgically proven iliopsoas bursitis were reviewed. All patients received conventional radiographs of the pelvis and hip, US and MR imaging of the hip. The CT was performed in 5 of the 18 patients. Ultrasound, CT and MR all demonstrated enlarged iliopsoas bursae. The bursal wall was thin and well defined in 83% and thickened in 17% of all cases. The two cases with septations on US were not seen by CT and MRI. A communication between the bursa and the hip joint was seen, and surgically verified, in all 18 patients by MR imaging, whereas US and CT failed to demonstrate it in 44 and 40% of the cases, respectively. Hip joint effusion was seen and verified by surgery in 16 patients by MRI, whereas CT (4 of 5) and US ( n=12) underestimated the number. The overall size of the bursa corresponded best between MRI and surgery, whereas CT and US tended to underestimate the size. Contrast enhancement of the bursal wall was seen in all cases. The imaging characteristics of iliopsoas bursitis are a well-defined, thin-walled cystic mass with a communication to the hip joint and peripheral contrast enhancement. The most accurate way to assess iliopsoas bursitis is with MR imaging; thus, it should be used for accurate therapy planning and follow-up studies. In order to initially prove an iliopsoas bursitis, US is the most cost-effective, easy-to-perform and fast alternative.

Asunto(s)

Bursitis/diagnóstico , Diagnóstico por Imagen , Femenino , Cadera , Articulación de la Cadera , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Músculos Psoas , Tomografía Computarizada por Rayos X

RESUMEN

BACKGROUND: To investigate the contribution of inflammation to postangioplasty lumen loss, we used an adenoviral gene therapy approach to inhibit the central inflammatory mediator nuclear factor-kappaB (NF-kappaB) by overexpression of its natural inhibitor, IkappaBalpha. METHODS AND RESULTS: The adenovirus carrying human IkappaBalpha was applied immediately after balloon dilatation by a double-balloon catheter in a rabbit iliac artery restenosis model. Immunohistochemistry of IkappaBalpha revealed that mainly smooth muscle cells of the media but also cells of the adventitia were transduced and expressed the transgene IkappaB alpha for >/= 8 days. At this time point, intercellular adhesion molecule-1 (30%) and monocyte chemotactic protein-1 (50%) expression, as well as recruitment of macrophages into the wounded area (90%), were significantly reduced in IkappaB alpha-treated vessels. In addition, expression of inhibitor of apoptosis proteins was reduced and the percentage of apoptotic cells was increased compared with control-treated contralateral vessels. Animals killed 5 weeks after treatment exhibited a significantly reduced degree of lumen narrowing (P<0.02) on the side treated with adenovirus IkappaBalpha. The lumen gain of approximately 40% was due to positive remodeling. CONCLUSIONS: From these data, we conclude that balloon angioplasty-induced activation of NF-kappaB contributes to lumen loss likely via induction of an inflammatory response and a decrease in the rate of apoptosis. These data show for the first time that inflammation mediated by NF-kappaB is involved in postangioplasty lumen narrowing. Specific and more potent inhibitors of NF-kappaB might therefore be a useful therapeutic measure to improve clinical outcome after balloon dilatation.

Asunto(s)

Oclusión de Injerto Vascular/metabolismo , Oclusión de Injerto Vascular/prevención & control , Proteínas I-kappa B , FN-kappa B/metabolismo , Adenoviridae/genética , Angiografía de Substracción Digital , Angioplastia de Balón/efectos adversos , Animales , Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CCL2/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/farmacología , Dieta Aterogénica , Modelos Animales de Enfermedad , Expresión Génica , Oclusión de Injerto Vascular/patología , Humanos , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/metabolismo , Arteria Ilíaca/patología , Inmunohistoquímica , Molécula 1 de Adhesión Intercelular/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , Infiltración Neutrófila/efectos de los fármacos , Conejos , Transgenes , Grado de Desobstrucción Vascular/efectos de los fármacos

RESUMEN

Currently contrast medium-enhanced, 3D magnetic resonance angiography enables fast and non-invasive depiction of the arterial vessels in the neck, thorax, abdomen, and limbs, which allows high sensitivity and specificity in the diagnostically evaluation of aneurysms, dissection and arterial stenosis. Intravenous bolus administration of a paramagnetic contrast medium is performed after timing of the bolus arrival time, thus enabling rapid acquisition of 3D datasets with high contrast between vessel lumen and surrounding soft tissue. Thorax and abdomen are examined within one breath-hold, the periphery of the extremities and the supra-aortal vessels can be imagined with longer sequences and even increased spatial resolution. Fast contrast-enhanced 3D magnetic resonance angiography--in combination with flow measurements--carries the potential to replace the additional functional information obtained by conventional digital subtraction angiography.

Asunto(s)

Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Angiografía por Resonancia Magnética , Enfermedades Vasculares/diagnóstico , Angiografía de Substracción Digital , Arterias/patología , Velocidad del Flujo Sanguíneo/fisiología , Contraindicaciones , Medios de Contraste/administración & dosificación , Diseño de Equipo , Humanos , Aumento de la Imagen , Sensibilidad y Especificidad

RESUMEN

The long-term success of infrainguinal bypass grafts depends on meticulous surgical technique and a periodic program of postoperative surveillance. Duplex scanning is the method of choice for the detection of stenotic lesions that threaten graft patency. As an alternative to surgery, PTA is gaining increasing acceptance for the treatment of non-recurrent, short, and single stenotic lesions, despite somewhat controversial opinions. The initial technical success rates for PTA were reported to be up to 100 %, and a 5-year primary assisted patency rate of up to 65 % has been achieved. Some authors favorize intra-arterial infusion of fibrinolytic agents for the treatment of bypass graft occlusion with technical success rates of up to 92 %. In addition to a reduced trauma compared to surgical thrombectomy, of the venous wall the advantage of thrombolytic therapy is clot lysis in run-off vessels, and uncovering of the stenotic lesions. This stenosis may then be treated by an endovascular or surgical approach.

Asunto(s)

Implantación de Prótesis Vascular , Oclusión de Injerto Vascular/tratamiento farmacológico , Isquemia/cirugía , Pierna/irrigación sanguínea , Terapia Trombolítica , Venas/trasplante , Angiografía , Angioplastia de Balón , Oclusión de Injerto Vascular/diagnóstico por imagen , Humanos , Isquemia/diagnóstico por imagen , Pronóstico

RESUMEN

PURPOSE: To evaluate the safety and performance of a recently developed expanded polytetrafluoroethylene (ePTFE)-covered nitinol stent-graft to create transjugular intrahepatic portosystemic shunt (TIPS) in patients with portal hypertension and related complications. MATERIALS AND METHODS: The ePTFE-covered nitinol stent-graft was used to create TIPS in 16 patients with recurrent variceal bleeding (n = 13) or refractory ascites (n = 3). Follow-up was performed with duplex ultrasonography, clinical assessment, and venography at 6 months. Technical success and portosystemic pressure gradients (PPGs) before and after stent-graft implantation and at follow-up were assessed. Two patients died during follow-up. Histopathologic follow-up data were available for one patient at autopsy and for the other after liver transplantation. RESULTS: The implantation technical success rate was 100%. Mean (+/- SD) PPG was reduced from 24 mm Hg +/- 5 to 9 mm Hg +/- 2. Histopathologic analysis of the explanted endoprostheses revealed no inflammatory response or neointima formation. The venographic follow-up data available for 10 patients demonstrated 100% in-graft patency (mean follow-up, 289 days +/- 26). Revisions with implantation of a new ePTFE-covered nitinol stent-graft or another commercially available stent in 10 patients were necessary because of hepatic vein stenosis above the grafted portion and/or relative diameter mismatch causing TIPS dysfunction. CONCLUSION: The ePTFE-covered nitinol stent-graft was used successfully to create TIPS and has the potential to prolong TIPS patency upon complete coverage to the hepatocaval junction.

Asunto(s)

Aleaciones , Hipertensión Portal/cirugía , Politetrafluoroetileno , Derivación Portosistémica Intrahepática Transyugular , Stents , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Prótesis e Implantes , Diseño de Prótesis

RESUMEN

OBJECTIVE: The aim of our study was to assess the frequency, efficacy, and incidence of adverse effects of internal iliac artery embolization. MATERIALS AND METHODS: Of 343 patients examined for stent-graft repair, 147 were suitable for endovascular treatment. Fifty-five patients underwent preprocedural embolization of the internal iliac artery either unilaterally (46 patients) or bilaterally (nine patients). Successful embolization was assessed angiographically and with helical CT follow-up examinations. Colonic ischemia was ruled out clinically or colonoscopically. Buttock claudication, and sexual dysfunction in men, were evaluated through a questionnaire. RESULTS: Embolization of the internal iliac artery increased by 16% the percentage of patients for whom endovascular repair was suitable. After successful embolization in all patients, routine CT follow-up examinations after a mean time of 16.7 months showed no evidence of endoleaks related to retrograde perfusion via embolized internal iliac arteries. Nevertheless, in all patients who had undergone embolization, a primary endoleak was detected in 43.4% at the first postoperative CT examination. None of our patients had evidence of colonic ischemia. Clinical follow-up data of 46 patients were available. Of these patients, mild to severe new onset buttock claudication was found in 13 (36.1%) of 36 patients with unilateral, and in eight (80%) of 10 patients with bilateral, internal iliac artery embolization (p = 0.03). Five (25%) of 20 men had an erectile dysfunction after the procedure. CONCLUSION: Embolization of the internal iliac artery is a safe and efficient procedure that increases the applicability for endovascular repair of aortoiliac aneurysms. However, buttock claudication and erectile dysfunction are a drawback in a substantial number of patients.

Asunto(s)

Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Embolización Terapéutica , Arteria Ilíaca , Cuidados Preoperatorios , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aortografía , Nalgas/irrigación sanguínea , Embolización Terapéutica/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Arteria Ilíaca/diagnóstico por imagen , Claudicación Intermitente/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento

RESUMEN

PURPOSE: To compare the biocompatibility and performance of various stent-grafts to those of a bare stent in an ovine model with a subchronic (3 months) endpoint. MATERIALS AND METHODS: Three different types of stent-grafts (ePTFE/nitinol, n = 8; polyester/nitinol, n = 8; and polycarbonate urethane/cobalt-alloy, n = 8) and a bare stent as a control (Ni-Co-Ti-steel-alloy, n = 8) were implanted in the iliac arteries in eight female sheep. One type of each stent-graft was implanted per animal, two implants at each side. The implantation sites for each type varied from animal to animal. Angiographic control and intravascular ultrasound (IVUS) imaging were performed before and after implantation, after 2 months, and before explantation at 3 months and were used to characterize patency and to assess intimal hyperplasia. After 3 months, the implants were retrieved and subjected to histologic evaluation (after methacrylate embedding, cutting, and histologic staining) to characterize the biologic response. RESULTS: Implantation was technically successful in all procedures. At 2 and 3 months after implantation, all segments in which stents had been implanted were patent. Marked neointima formation was found in the polyester-covered stent-graft that showed significant luminal narrowing of 50%, compared to the ePTFE-covered (24%) and polycarbonate urethane-covered endoprostheses (22%), as well as the bare stent (Wallstent; 9%; P < .001). A minimal inflammatory vessel wall reaction was demonstrated for the polyester-covered and ePTFE-covered endoprostheses; the polycarbonate urethane-covered stent-graft's response was demonstrable but not significantly different from that of the Wallstent. At 3 months, the ePTFE-covered stent-graft showed incomplete (>90%) endothelial coverage; in the other endoprostheses, complete but partially immature endothelialization was found. CONCLUSION: All stent-grafts induced an inflammatory vessel wall reaction with neointimal hyperplasia. The polyester-covered endoprosthesis caused a marked reaction with 50% luminal stenosis. Endothelialization was retarded with the ePTFE-covered stent-graft. The bare stent performed best in regard to neointimal formation and caused the least inflammatory response.

Asunto(s)

Materiales Biocompatibles , Prótesis Vascular , Arteria Ilíaca , Stents , Aleaciones , Animales , Implantación de Prótesis Vascular , Femenino , Hiperplasia , Poliésteres , Politetrafluoroetileno , Ovinos , Factores de Tiempo , Túnica Íntima/patología , Grado de Desobstrucción Vascular

RESUMEN

PURPOSE: To evaluate if stent placement is superior to percutaneous transluminal angioplasty (PTA) in the treatment of chronic symptoms in short femoropopliteal arterial lesions. MATERIALS AND METHODS: One hundred fifty-four limbs in 141 patients who ranged in age from 39 to 87 years (mean age, 67 years) were randomized to PTA (n = 77) versus PTA followed by implantation of Palmaz stents (n = 77). Inclusion criteria were patients with intermittent claudication (n = 108, Society of Vascular Surgery/International Society of Cardiovascular Surgery [SVS-ISCVS] categories 1-3) or chronic critical limb ischemia (n = 46 with either ischemic rest pain [category 4] or minor tissue loss [category 5]), short stenosis or occlusion (lesion length < or = 5 cm), and at least one patent run-off vessel at angiography. Follow-up included clinical assessment, measurement of ankle/ brachial index (ABI), color duplex ultrasound, and/or angiography at 6 or 12 months. Angiographic follow-up between 12 and 36 months was available in 46 limbs (29.9%). RESULTS: In the PTA group, initial technical success was achieved in 65 of 77 limbs (84%) versus 76 of 77 (99%) limbs in the stent group (chi2 value = 0.009). Overall, major complications occurred in 3.9% (n = 6); n = 4 in the PTA group compared to n = 2 in the stent group. There was no difference between groups of treatment: hemodynamic/clinical success at 1 and 2 years in the PTA group was 72% and 65% versus 77% and 65% in the stent group (Gehan P value = .26). The cumulative 1- and 2-year angiographic primary patency rates were 63% and 53%, respectively, for both groups. The secondary 1- and 2-year angiographic patency rates were 86% and 74% in the PTA group versus 79% and 73% in the stent group (P = .5). CONCLUSION: After stent placement, the primary success rate was significantly higher than after PTA. However, 1-year angiographic and clinical/hemodynamic success was not improved.

Asunto(s)

Angioplastia de Balón , Claudicación Intermitente/terapia , Isquemia/terapia , Pierna/irrigación sanguínea , Stents , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Arteria Femoral , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Arteria Poplítea , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del Tratamiento

RESUMEN

PURPOSE: The stenosis or occlusion of transjugular intrahepatic portosystemic shunt (TIPS) occurs in up to 75% of patients within 12 months after treatment. The aim of our investigation was to evaluate the feasibility, safety and efficacy of intraluminal high-dose rate brachytherapy (HDRBT) with Iridium-192 following TIPS revision to prevent restenosis due to pseudointimal hyperplasia. MATERIALS AND METHODS: Between September and November 1996, intraluminal BT was performed in five patients after TIPS revision. The indications for initial TIPS were a Budd-Chiari syndrome in two female patients and recurrent variceal bleeding by alcoholic liver cirrhosis in three male patients. TIPS was created with Wallstents (10 mm diameter in four patients) and Palmaz stent (10 mm diameter in one patient). The re-dilatation was done in all five patients 6 months after first stenting because of restenosis (>50% stent lumen reduction) or occlusion of the stent. A 5-French closed-tip, noncentered BT delivery catheter was used for subsequent radiotherapy. The whole length of the stent and performed dilatation (interventional length - IL) was taken as clinical target length (CTL). A 10-mm safety margin was added proximal and distal to the CTL due to uncertainties of BT source positioning, so forming the planning target length (PTL). To ensure that prescribed dose covers the whole PTL, the active source length (ASL) was 5 mm longer proximal and distal than PTL, so forming the reference isodose length (RIL). A dose of 12 Gy was prescribed in 3 mm distance from the source axis in the mid-plane of the applicator for three patients and in 5 mm distance for two patients. RESULTS: A normal patency (<50% lumen reduction) of the stent was achieved at 44 months follow-up (duplex sonography+portography) in all three patients with liver cirrhosis, whereas further revisions were necessary in two patients with Budd-Chiari syndrome (after 5.5 and 18 months). No acute, subacute or late brachytherapy (BT)-related side effects were seen until now. CONCLUSIONS: HDRBT following TIPS revision was safe and feasible in all patients. The exact impact of BT on the TIPS patency should be evaluated in larger clinical trials. Moderate dose escalation and use of today's commercially available centering radiation catheters seem to be necessary.

Asunto(s)

Braquiterapia/efectos adversos , Constricción Patológica/prevención & control , Constricción Patológica/radioterapia , Radioisótopos de Iridio/uso terapéutico , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Adulto , Síndrome de Budd-Chiari/complicaciones , Estudios de Factibilidad , Femenino , Humanos , Cirrosis Hepática Alcohólica/complicaciones , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reoperación/efectos adversos , Prevención Secundaria , Factores de Tiempo , Resultado del Tratamiento

RESUMEN

PURPOSE: Retrospective analysis of the results of rt-PA thrombolysis in the treatment of acute thromboembolic occlusion of the upper limb. METHODS: Of 55 patients with demonstrated acute embolic arterial occlusion, rt-PA thrombolysis was performed on 40 occlusions in 38 patients (23 women with a mean age of 62 years, range 32-85 years; 15 men with a mean age of 65 years, range 32-92 years) according to the following design: 6 mg rt-PA/hr for 30 min, 3 mg rt-PA/hr for the next 30 min, 1 mg rt-PA/hr for 7 hr, and 0.4 mg rt-PA/hr until the end of lysis. Onset of symptoms varied from 1 to 14 days. Included were three isolated upper-arm occlusions, nine combined brachial and forearm occlusions, and 28 forearm and hand artery occlusions. RESULTS: The overall success rate was 55%. The lysis results for isolated upper arm, combined brachial and forearm occlusions, and forearm and hand artery occlusions were 100%, 66%, and 46%, respectively. In eight patients surgical embolectomy had to be performed after failed thrombolysis. No amputation was required in the follow-up period. No lethal complications occurred. CONCLUSIONS: Interventional rt-PA treatment of proximal upper-extremity arterial occlusions may be performed with comparable success rates to surgical embolectomy and without severe complications. For distal occlusions the results are inferior to the success rates obtained with surgery.

Asunto(s)

Brazo/irrigación sanguínea , Tromboembolia/tratamiento farmacológico , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Arteria Braquial/diagnóstico por imagen , Embolectomía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Tromboembolia/diagnóstico por imagen , Tromboembolia/etiología , Tromboembolia/cirugía

RESUMEN

BACKGROUND: Magnetic resonance (MR)-guided biopsies are generally regarded as complex interventions. We implemented interventional MR (IMR) with the resources available in and for practical application in a large (1100 beds) central hospital. METHODS: This simple and straightforward IMR technique uses a step-by-step approach for localization, access route planning, biopsy, verification in at least two planes, and postoperative control. The technique has been used and evaluated unchanged for more than 400 punctures and interventions. RESULTS: Contrast, signal, matrix options, and visibility of needle track and tip permit uncomplicated orientation. The mean duration of a biopsy is 19 min. The technique can be applied to all radiologic puncture settings without any technical or medical complications. CONCLUSION: The crucial step in implementing IMR is not to contemplate its application but to simply start applying the procedure.

Asunto(s)

Biopsia con Aguja/métodos , Imagen por Resonancia Magnética , Anciano , Artefactos , Femenino , Humanos , Masculino , Persona de Mediana Edad

RESUMEN

PURPOSE: To evaluate the safety and efficacy of an endoluminal prosthesis for treatment of peripheral arterial occlusive disease (PAOD). MATERIALS AND METHODS: A self-expanding endoprosthesis with an expanded polytetrafluoroethylene tube inside a nitinol support structure was implanted in 127 patients with symptomatic PAOD in the iliac (61 limbs) and femoral arteries (80 limbs). Clinical category status, ankle-brachial index, and color duplex flow imaging results were recorded before treatment, at discharge, and at 1, 3, 6, and 12 months after treatment. Aspirin was administered throughout the study, and heparin was administered during and for 2 days after the procedure. RESULTS: Endoprosthesis deployment was technically successful in all patients. Complications occurred in 24 of 141 procedures and included three major complications. Early thrombosis (within 30 days) occurred in one iliac and three femoral arteries. Late restenosis or reocclusion was observed in five iliac and 14 femoral arteries within the 1st year. Primary patency rates in iliac arteries were 98% +/- 3% (standard error) and 91% +/- 4%, respectively, at 6 and 12 months after treatment. Primary patency rates in femoral arteries were 90% +/- 3% and 79% +/- 5%, respectively, at 6 and 12 months. Secondary patency rates were 95% and 93% for iliac and femoral arteries, respectively, at 12 months after treatment. CONCLUSION: The device used in this study can be implanted without additional risks to the patient and provided encouraging patency rates up to 1 year.

Asunto(s)

Arteriopatías Oclusivas/terapia , Enfermedades Vasculares Periféricas/terapia , Stents , Adulto , Anciano , Anciano de 80 o más Años , Aleaciones , Angiografía de Substracción Digital , Diseño de Equipo , Estudios de Evaluación como Asunto , Femenino , Arteria Femoral , Humanos , Arteria Ilíaca , Tablas de Vida , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Estudios Prospectivos , Factores de Riesgo , Resultado del Tratamiento , Grado de Desobstrucción Vascular

RESUMEN

The purpose of this study was to compare the diagnostic efficacy of a newly developed T(1)-weighted three-dimensional segmented echo planar imaging (3D EPI) sequence versus a conventional T(1)-weighted three dimensional spoiled gradient echo (3D GRE) sequence in the evaluation of brain tumors. Forty-four patients with cerebral tumors and infections were examined on a 1.0 T MR unit with 23 mT/m gradient strength. The total scan time for the T(1) 3D EPI sequence was 2 min 12 s, and for a conventional 3D GRE sequence it was 4 min 59 s. Both sequences were performed after administration of a contrast agent. The images were analyzed by three radiologists. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, and image artifacts. In addition, signal-to-noise and contrast-to-noise-ratio (C/N) were calculated. The gray-white differentiation and C/N ratio of 3D EPI were found to be inferior to conventional 3D GRE images, but the difference was not statistically significant. In the qualitative comparison, lesion detection and conspicuity of 3D EPI images and conventional 3D GRE images were similar, but a tow-fold reduction of the scanning time was obtained. With the 3D EPI technique, a 50% scan time reduction could be achieved with acceptable image quality compared to conventional 3D GRE. Thus, the 3D EPI technique could replace conventional 3D GRE in the preoperative imaging of brain.

Asunto(s)

Neoplasias Encefálicas/diagnóstico , Imagen Eco-Planar/métodos , Adulto , Femenino , Humanos , Masculino , Cuidados Preoperatorios