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BACKGROUND: The popliteal artery is highly exposed to biomechanical stress, which is the primary factor associated with stent failure. However, information on the optimal endovascular treatment for the popliteal artery is lacking. OBJECTIVE: To report the efficacy of the GORE® TIGRIS® Vascular Stent for the endovascular treatment of popliteal artery lesions. METHODS: Retrospective analysis of all patients with symptoms of peripheral artery occlusive disease (PAD) and popliteal artery lesions who underwent implantation of a GORE® TIGRIS® Vascular Stent between August 2012 and August 2014 at a tertiary vascular centre. RESULTS: Between August 2012 and August 2014, 48 patients (32 men, aged 75±8 years) were treated with a GORE® TIGRIS® Vascular Stent. The technical success rate was 100%. At 12 months, the primary and secondary patency rates were 74% and 85%, respectively. During follow-up, no stent fracture was observed. No major amputations were performed. CONCLUSIONS: Our study showed that isolated popliteal artery lesions in patients with symptomatic PAD could easily be treated with the GORE® TIGRIS® Vascular Stent, as good short-term results were achieved at 12 months. Therefore, the discontinuation of this product removed a useful tool with a simple release mechanism from the endovascular armamentarium of vascular specialists.
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Artéria Poplítea , Stents , Humanos , Artéria Poplítea/cirurgia , Masculino , Idoso , Feminino , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Doença Arterial Periférica , Procedimentos Endovasculares/métodos , Resultado do TratamentoRESUMO
Background: Endovascular treatment of calcified peripheral artery lesions may be associated with suboptimal vessel expansion, increased complication risk, and reduced long-term patency. The primary endpoint from the Disrupt PAD III randomized controlled trial (RCT) demonstrated superior procedural success in patients treated with intravascular lithotripsy (IVL) vs percutaneous transluminal angioplasty (PTA). The present study evaluates primary patency after 1 and 2 years in this randomized population. Methods: The Disrupt PAD III RCT enrolled 306 patients with moderately-to-severely calcified femoropopliteal arteries treated with IVL (n = 153) or PTA (n = 153) prior to DCB treatment or stenting. The powered secondary effectiveness endpoint was primary patency at 1 year, defined as freedom from clinically driven target lesion revascularization plus freedom from restenosis determined by duplex ultrasound. Acute PTA failure requiring stent placement during the index procedure was prespecified as a loss of primary patency. Results: Primary patency at 1 year was significantly greater in the IVL arm (80.5% vs 68.0%, P = .017). The requirement for provisional stenting was significantly lower in the IVL group (4.6% vs 18.3%, P < .0001). Freedom from clinically driven target lesion revascularization (IVL: 95.7% vs PTA: 98.3%, P = .94) and restenosis rates (IVL: 90.0% vs PTA: 88.8%, P = .48) were similar between the 2 groups at 1 year. At 2 years, primary patency remained significantly greater in the IVL arm (70.3% vs 51.3%, P = .003). Conclusions: The Disrupt PAD III RCT secondary endpoint of superior 1-year primary patency was achieved, confirming the consistent safety and effectiveness of IVL followed by DCB treatment to facilitate a durable approach for patients with heavily calcified femoropopliteal arteries largely without stent requirement.
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OBJECTIVES: The study sought to compare short-term outcomes in patients with femoropopliteal artery calcification receiving vessel preparation with intravascular lithotripsy (IVL) or percutaneous transluminal angioplasty (PTA) prior to drug-coated balloon (DCB) for symptomatic peripheral artery disease. BACKGROUND: Endovascular treatment of calcified peripheral artery lesions is associated with suboptimal vessel expansion and increased complication risk. Although initial results from single-arm studies with IVL have been reported, comparative evidence from randomized trials is lacking for most devices in the presence of heavy calcification. METHODS: The Disrupt PAD III (Shockwave Medical Peripheral Lithoplasty System Study for PAD) randomized trial enrolled patients with moderate or severe calcification in a femoropopliteal artery who underwent vessel preparation with IVL or PTA prior to DCB or stenting. The primary endpoint was core lab-adjudicated procedural success (residual stenosis ≤30% without flow-limiting dissection) prior to DCB or stenting. RESULTS: In patients receiving IVL (n = 153) or PTA (n = 153), procedural success was greater in the IVL group (65.8% vs. 50.4%; p = 0.01) and the percentage of lesions with residual stenosis ≤30% (66.4% vs. 51.9%; p = 0.02) was greater in the IVL group, while flow-limiting dissections occurred more frequently in the PTA group (1.4% vs. 6.8%; p = 0.03). Post-dilatation (5.2% vs. 17.0%; p = 0.001) and stent placement (4.6% vs. 18.3%; p < 0.001) were also greater in the PTA group. The rates of major adverse events (IVL: 0% vs. PTA: 1.3%; p = 0.16) and clinically driven target lesion revascularization (IVL: 0.7% vs. PTA: 0.7%; p = 1.0) at 30 days were comparable between groups. CONCLUSIONS: IVL is an effective vessel preparation strategy that facilitates definitive endovascular treatment in calcified femoropopliteal arteries in patients with peripheral artery disease. (Shockwave Medical Peripheral Lithoplasty System Study for PAD [Disrupt PAD III]; NCT02923193).
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Angioplastia com Balão , Litotripsia , Doença Arterial Periférica , Calcificação Vascular , Angioplastia com Balão/efeitos adversos , Materiais Revestidos Biocompatíveis , Artéria Femoral/diagnóstico por imagem , Humanos , Litotripsia/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Estudos Prospectivos , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia , Grau de Desobstrução VascularRESUMO
BACKGROUND: Drug coated balloon (DCB) angioplasty significantly reduces reintervention rates in patients with symptomatic femoropopliteal peripheral artery disease (PAD). However, stand-alone DCB use in long, severely calcified lesions is frequently associated with vessel recoil and/or high-grade dissections necessitating provisional stent implantation. OBJECTIVES: Assess the safety and effectiveness of a vessel preparation strategy with directional atherectomy (DA) prior to DCB angioplasty in patients with symptomatic severely calcified femoropopliteal PAD. METHODS: REALITY (NCT02850107) prospectively enrolled subjects at 13 multinational centers with 8-36 cm femoropopliteal stenoses or occlusions with bilateral vessel wall calcification treated with DA prior to DCB angioplasty. The primary effectiveness endpoint was 12-month primary patency, and the primary safety endpoint was freedom from major adverse events through 30 days. Independent angiographic and duplex core laboratories assessed outcomes and a Clinical Events Committee adjudicated events. RESULTS: A total of 102 subjects were enrolled; one lesion was treated per subject. The mean lesion length was 17.9 ± 8.1 cm, 39.0% were chronic total occlusions (mean lesion length 22.6 ± 8.6 cm); 86.2% of lesions exhibited moderate to severe bilateral calcification. Provisional stents were implanted in 8.8% (9/102) of subjects. Twelve-month primary patency rate was 76.7% (66/86) and freedom from CD-TLR rate was 92.6% (87/94). No device or procedure related deaths and one index-limb major amputation were reported. CONCLUSIONS: Plaque excision with DA in patients with symptomatic severely calcified femoropopliteal arterial disease prior to DCB angioplasty is a safe and effective treatment strategy with a low provisional stent rate.
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Angioplastia com Balão , Fármacos Cardiovasculares , Doença Arterial Periférica , Angioplastia com Balão/efeitos adversos , Aterectomia/efeitos adversos , Fármacos Cardiovasculares/efeitos adversos , Materiais Revestidos Biocompatíveis , Artéria Femoral/diagnóstico por imagem , Humanos , Paclitaxel/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
BACKGROUND: Type 2 endoleaks (T2EL) are the most frequent complication following endovascular aortic repair. Multiple studies primarily deal with the technical and clinical success of the embolization of persisting T2EL, thereby revealing controversial outcomes. Current reports rarely focus on the detailed execution of such a complex interventional procedure with respect to the difficult anatomic setting. METHODS: The present review provides an in-depth depiction and evaluation of the interventional methodology of the embolization of T2EL in the abdominal aorta with use of ethylene vinyl alcohol copolymer (EVOH). Complicating anatomic conditions are taken into account as well as technical and clinical success rates. RESULTS: Using the transarterial approach, there are at least 4 different pathways to access the nidus of a T2EL. CT-guided direct puncture of the aneurysm sac provides an alternative method of high technical success. EVOH with its slow solidification characteristics enables good control to achieve complete filling of the T2EL. During the intervention, however, it remains difficult to meet exactly the embolization endpoint, especially in large T2ELs. CONCLUSION: T2EL embolization using EVOH is an effective treatment with low major complication rates when conducted by skilled interventionists with detailed knowledge of diverse complex access routes. KEY POINTS: · Many roads lead to Rome to access the nidus of a T2EL including diverse complex transarterial pathways and direct aneurysm sac puncture.. · Ethylene vinyl alcohol co-polymer enables good control for slow filling of the nidus with low risk of major complications.. · Identification of the embolization endpoint remains difficult during the procedure and may result in secondary interventions.. · Successful T2EL embolization requires detailed knowledge of all access routes to the nidus and skilled handling of liquid embolics.. CITATION FORMAT: · Nolte-Ernsting C, Mecklenbeck F, Stehr A. Embolization of Type 2 Endoleaks in the Abdominal Aorta Using Ethylene Vinyl Alcohol Copolymer. Fortschr Röntgenstr 2021; 193: 1426â-â1435.
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Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Aorta Abdominal , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Endoleak/cirurgia , Endoleak/terapia , Humanos , Polivinil , Estudos Retrospectivos , Fatores de TempoRESUMO
Background: This study aimed to evaluate a Multiple Stent Delivery System for provisional focal stenting of the femoropopliteal artery. Patient and methods: The LOCOMOTIVE EXTENDED study (Multi-LOC for flOw liMiting Outcomes after plain old balloon angioplasty and/or drug-coated balloon Treatment in the infrainguinal position with the objectIVE to implant multiple stent segments) is a prospective, single-arm, multicentre observational study. The Multi-LOC Multiple Stent Delivery System (B.Braun, Melsungen, Germany) was used for provisional focal stenting of the femoropopliteal artery. We enrolled 357 patients with 449 femoropopliteal lesions; all had flow-limiting dissections or recoil following angioplasty. Eligibility included Rutherford classification 2 to 5 with a de novo or non-stented restenotic femoropopliteal lesion undergoing plain balloon or drug-coated balloon angioplasty. The 6- and 12-month efficacy endpoints encompassed target lesion revascularisation and primary patency rates. Results: The mean patient age was 71 ± 10 years. The mean lesion length was 16.0 ± 9.7 cm; 44.5% were TASC II C/D lesions and 31.4% were chronic total occlusions. By operator choice, 45% of the patients underwent drug-coated balloon angioplasty. On average, 4.0 stents (each 13 mm long) were placed in each lesion, resulting in a scaffolding proportion of 56% of the total lesion length with a technical success rate of 98.3%. At 6 and 12 months, the freedom from clinically driven target lesion revascularisation was 95.5% and 88.7% and the primary patency rates were 88.7% and 82.3%, respectively. At 12 months, significant improvements were noted in Rutherford categories and ankle-brachial indices. In multiple regression analyses, both diabetes mellitus and no distal run-off vessel showed a trend toward worse TLR, while other factors such as DCB predilation or the lesion length were not predictive. Conclusions: The LOCOMOTIVE EXTENDED study demonstrated the safety and efficacy of the Multi-LOC stent system for focal provisional stenting of complex femoropopliteal lesions.
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Angioplastia com Balão , Doença Arterial Periférica , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Artéria Femoral/diagnóstico por imagem , Alemanha , Humanos , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Estudos Prospectivos , Stents , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
Background: Previous studies showed favorable results after treatment of femoropopliteal lesions with the Pulsar-18 self-expanding (SE) nitinol stent. The objective of this registry was to evaluate whether these results will be confirmed in a real-world setting with varying stenting strategies. Patients and methods: In this prospective, observational trial, 160 patients with 186 femoropopliteal lesions were treated with the Pulsar-18 SE nitinol stent at 9 German sites. Mean lesion length was 116 ± 103 mm, and 41.9 % of the lesions were moderately or heavily calcified. Eighty lesions were concomitantly treated with drug-coated balloon (DCB). Main effectiveness outcome was primary patency at 12 months, and main safety outcome was freedom from the composite of device or procedure related death, major target limb amputation, and clinically driven target lesion revascularization (TLR) at 30 days and 6 months. Results: Kaplan-Meier estimate of primary patency was 89.1 %, 67.3 %, and 57.1 % at 6, 12, and 24 months. Freedom from TLR was 95.5 %, 91.4 %, and 85.2 % at 6, 12, and 24 months, respectively. Lesions, which were additionally treated with DCB (plus DCB-group), were longer (150 versus 82 mm on average, p < 0.0001), and associated with lower primary patency estimates than those without DCB angioplasty (stent-only-group) (log-rank p = 0.006). However, there was no difference in freedom from TLR between groups (log-rank p = 0.542). Improvement by ≥ 1 Rutherford category was achieved in 84.8 %, 81.0 %, and 81.7 % of patients at 6, 12, and 24 months, respectively. Walking distance and patient-reported pain improved persistently through 24 months (p < 0.001). Hemodynamic improvement was achieved in 68.2 %, 73.7 %, and 70.7 % of the patients at 6, 12, and 24 months, respectively. Conclusions: The Pulsar-18 self-expanding nitinol stent with optional drug-coated balloon angioplasty can be considered an efficacious and safe therapy option for endovascular treatment of femoropopliteal artery disease.
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Angioplastia com Balão , Doença Arterial Periférica , DEAE-Dextrano , Artéria Femoral , Humanos , Artéria Poplítea , Estudos Prospectivos , Sistema de Registros , Stents , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
BACKGROUND The aim of this study was to evaluate the safety and efficacy of DSM (degradable starch microspheres) as an embolic agent in transarterial chemoembolization in the treatment of intrahepatic cholangiocellular carcinoma (ICC). MATERIAL AND METHODS This was a national, multi-center observational cohort study on the safety and efficacy of DSM-TACE using mitomycin, gemcitabine, cisplatin, doxorubicin, and carboplatin in palliative treatment of ICC. Recruitment period for the study was from January 2010 to June 2014. Primary endpoints were toxicity, safety, and response according to mRECIST criteria. RESULTS Twenty-five DSM-TACE procedures in cases of advanced ICC were performed in seven patients. Nausea and vomiting occurred as adverse event (AE) in eight out of 25 treatments (32%), with seven of eight events (87.5%) associated with the use of gemcitabine. In 11 out of 25 treatments (44%) moderate, transient epigastric pain was registered as an adverse event (AE) within 24 hours of DSM-TACE. One case (1/25) of severe AE (4%) with thrombocytopenia led to discontinuation of the DSM-TACE-treatment. A total of 25 DSM-TACE procedures with complete clinical and imaging follow-up over a two-year-period were analyzed: objective response (OR) was achieved in three of 25 treatments (12%) Disease control (DC) was achieved in 44% (11/25) of treatments; progress was registered in 4% (1/25). CONCLUSIONS The use of DSM as an embolic agent for TACE is safe in the treatment of ICC. A standardized anti-emetic medication should be established, especially when using gemcitabine. Further prospective studies need to be conducted to find the most suitable, standardized DSM-TACE treatment regime.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias dos Ductos Biliares/terapia , Quimioembolização Terapêutica/métodos , Colangiocarcinoma/terapia , Amido/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Ductos Biliares Intra-Hepáticos , Carboplatina/administração & dosagem , Quimioembolização Terapêutica/efeitos adversos , Cisplatino/administração & dosagem , Estudos de Coortes , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Doxorrubicina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , GencitabinaRESUMO
PURPOSE: To evaluate the 1-year patency of the 4-F Pulsar-18 self-expanding nitinol stent for treatment of femoropopliteal occlusive disease in a national, prospective, multicenter, all-comers registry. METHODS: Between January and June 2012, the German PEACE I all-comers prospective registry enrolled 148 patients with symptomatic femoropopliteal lesions (Rutherford category 2-5) undergoing recanalization and implantation of the Pulsar-18 SE nitinol stent at 6 clinical centers. Thirty patients did not have the 12-month follow-up visit (18 declined reevaluation, 5 withdrew consent, and 7 died), leaving 118 patients (64 men; mean 71.9±9.6 age years) for the 1-year evaluation. The average lesion length was 111.5±71.4 mm, and 38 of the 118 lesions were classified as TASC II D. More than half the lesions (67, 56.7%) were chronic total occlusions (CTO). The popliteal segment was involved in 22 (18.7%) lesions. The mean stented length was 122.7±64.5 mm. Routine follow-up included duplex ultrasound at 6 and 12 months. Outcome measures were primary patency and no clinically driven target lesion revascularization (TLR) within 12 months. RESULTS: The overall primary patency rates after 6 and 12 months were 87.4% and 79.5%, respectively; in the popliteal segments, the rate was 71.4% after 12 months. The overall freedom from TLR was 93.2% after 6 months and 81% after 12 months. Ankle-brachial index, pain-free walking distance, and Rutherford category all improved significantly (p<0.0001) after 6 and 12 months. The primary patency rates in patients with diabetes (p=1.0) and those with renal insufficiency (p=0.8) were not significantly lower compared to the overall rate. There was no significant difference (p=0.67) in restenosis rate for recanalization of CTOs compared to non-CTO lesions. CONCLUSIONS: In this all-comers registry, the use of the Pulsar-18 self-expanding nitinol stent in femoropopliteal lesions averaging 111.5 mm long showed promising primary patency and freedom from TLR after 6 and 12 months. Diabetes had no negative impact on patency. Primary patency in the popliteal segments was acceptable at 12 months.
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Ligas , Angioplastia/instrumentação , Artéria Femoral/fisiopatologia , Doença Arterial Periférica/terapia , Artéria Poplítea/fisiopatologia , Stents , Grau de Desobstrução Vascular , Idoso , Idoso de 80 Anos ou mais , Angioplastia/efeitos adversos , Constrição Patológica , Intervalo Livre de Doença , Feminino , Artéria Femoral/diagnóstico por imagem , Alemanha , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Estudos Prospectivos , Desenho de Prótese , Recidiva , Sistema de Registros , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler DuplaRESUMO
The aim was to develop clinical guidelines for multidetector computed tomography urography (CTU) by a group of experts from the European Society of Urogenital Radiology (ESUR). Peer-reviewed papers and reviews were systematically scrutinized. A summary document was produced and discussed at the ESUR 2006 and ECR 2007 meetings with the goal to reach consensus. True evidence-based guidelines could not be formulated, but expert guidelines on indications and CTU examination technique were produced. CTU is justified as a first-line test for patients with macroscopic haematuria, at high-risk for urothelial cancer. Otherwise, CTU may be used as a problem-solving examination. A differential approach using a one-, two- or three-phase protocol is proposed, whereby the clinical indication and the patient population will determine which CTU protocol is employed. Either a combined nephrographic-excretory phase following a split-bolus intravenous injection of contrast medium, or separate nephrographic and excretory phases following a single-bolus injection can be used. Lower dose (CTDIvol 5-6 mGy) is used for benign conditions and normal dose (CTDIvol 9-12 mGy) for potential malignant disease. A low-dose (CTDIvol 2-3 mGy) unenhanced series can be added on indication. The expert-based CTU guidelines provide recommendations to optimize techniques and to unify the radiologist's approach to CTU.
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Tomografia Computadorizada por Raios X/métodos , Urografia/métodos , Doenças Urológicas/diagnóstico por imagem , Meios de Contraste , Humanos , Interpretação de Imagem Radiográfica Assistida por ComputadorRESUMO
BACKGROUND: To analyze clinical courses and outcome of postpancreatectomy hemorrhage (PPH) after major pancreatic surgery. SUMMARY BACKGROUND DATA: Although PPH is the most life-threatening complication following pancreatic surgery, standardized rules for its management do not exist. METHODS: Between 1992 and 2006, 1524 patients operated on for pancreatic diseases were included in a prospective database. A risk stratification of PPH according to the following parameters was performed: severity of PPH classified as mild (drop of hemoglobin concentration <3 g/dL) or severe (>3 g/dL), time of PPH occurrence (early, first to fifth postoperative day; late, after sixth day), coincident pancreatic fistula, intraluminal or extraluminal bleeding manifestation, and presence of "complex" vascular pathologies (erosions, pseudoaneurysms). Success rates of interventional endoscopy and angiography in preventing relaparotomy were analyzed as well as PPH-related overall outcome. RESULTS: Prevalence of PPH was 5.7% (n = 87) distributed almost equally among patients suffering from malignancies, borderline tumors, and focal pancreatitis (n = 47) and from chronic pancreatitis (n = 40). PPH-related overall mortality of 16% (n = 14) was closely associated with 1) the occurrence of pancreatic fistula (13 of 14); 2) vascular pathologies, ie, erosions and pseudoaneurysms (12 of 14); 3) delayed PPH occurrence (14 of 14); and 4) underlying disease with lethal PPH found only in patients with soft texture of the pancreatic remnant, while no patient with chronic pancreatitis died. Conversely, primary severity of PPH (mild vs. severe) and the kind of index operation (Whipple resection, pylorus-preserving partial pancreaticoduodenectomy, organ-preserving procedures) had no influence on outcome of PPH. Endoscopy was successful in 3 from 15 patients (20%), who had intraluminal PPH within the first or second postoperative day. "True," early extraluminal PPH had uniformly to be treated by relaparotomy. Seventeen patients had "false," early extraluminal PPH due to primarily intraluminal bleeding site from the pancreaticoenteric anastomosis with secondary disruption of the anastomosis. From 43 patients subjected to angiography, 25 underwent interventional coiling with a success rate of 80% (n = 20). Overall, relaparotomy was performed in 60 patients among whom 33 underwent surgery as first-line treatment, while 27 were relaparotomied as rescue treatment after failure of interventional endoscopy or radiology. CONCLUSION: Prognosis of PPH depends mainly on the presence of preceding pancreatic fistula. Decision making as to the indication for nonsurgical interventions should consider time of onset, presence of pancreatic fistula, vascular pathologies, and the underlying disease.
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Embolização Terapêutica/métodos , Endoscopia Gastrointestinal/métodos , Hemorragia Gastrointestinal , Hemostasia Cirúrgica/métodos , Pancreatectomia/métodos , Pancreatopatias/cirurgia , Hemorragia Pós-Operatória , Angiografia/métodos , Seguimentos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/terapia , Hemostase Endoscópica , Humanos , Laparotomia , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/terapia , Prevalência , Estudos Prospectivos , Reoperação , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
PURPOSE: To evaluate MRI for a qualitative and quantitative in vivo tracking of intraaortal injected iron oxide-labeled mesenchymal stem cells (MSC) into rats with acute kidney injury (AKI). MATERIALS AND METHODS: In vitro MRI and R2* measurement of nonlabeled and superparamagnetic iron oxide (SPIO)-labeled MSC (MSC(SPIO)) was performed in correlation to cellular iron content and cytological examination (Prussian blue, electron microscopy). In vivo MRI and R2* evaluation were performed before and after ischemic/reperfusion AKI (N = 14) and intraaortal injection of 1.5 x 10(6) MSC(SPIO) (N = 7), fetal calf serum (FCS) (medium, N = 6), and SPIO alone (N = 1) up to 14 days using a clinical 3T scanner. Signal to noise ratios (SNR), R2* of kidneys, liver, spleen, and bone marrow, renal function (creatinine [CREA], blood urea nitrogen [BUN]), and kidney volume were measured and tested for statistical significance (Student's t-test, P < 0.05) in comparison histology (hematoxylin and eosin [H&E], Prussian blue, periodic acid-Schiff [PAS], CD68). RESULTS: In vitro, MSC(SPIO) showed a reduction of SNR and T2* with R2* approximately number of MSC(SPIO) (R2 = 0.98). In vivo MSC(SPIO) administration resulted in a SNR decrease (35 +/- 15%) and R2* increase (101 +/- 18.3%) in renal cortex caused by MSC(SPIO) accumulation in contrast to control animals (P < 0.01). Liver, spleen, and bone marrow (MSC(SPIO)) showed a delayed SNR decline/R2* increase (P < 0.05) resulting from MSC(SPIO) migration. The increase of kidney volume and the decrease in renal function (P < 0.05) was reduced in MSC-treated animals. CONCLUSION: Qualitative and quantitative in vivo cell-tracking and monitoring of organ distribution of intraaortal injected MSC(SPIO) in AKI is feasible in MRI at 3T.
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Isquemia/diagnóstico , Isquemia/terapia , Rim/citologia , Imageamento por Ressonância Magnética/métodos , Transplante de Células-Tronco Mesenquimais , Animais , Meios de Contraste , Dextranos , Estudos de Viabilidade , Óxido Ferroso-Férrico , Processamento de Imagem Assistida por Computador , Injeções Intra-Arteriais , Ferro , Isquemia/fisiopatologia , Nanopartículas de Magnetita , Óxidos , Ratos , Ratos Sprague-Dawley , Coloração e RotulagemRESUMO
The purpose of this study was to evaluate the possibility of reducing X-ray exposure during multidetector CT urography (MDCTU) considering image quality using a porcine model. MDCTU was performed in eight healthy pigs. Scanning was conducted using a gradual reduction of the tube current-time product at 120 kV [200-20 mAs (eff.) in ten steps]. Three blinded observers independently evaluated the image data for anatomic detail, subjective image quality, and subjective image noise. Overall image quality was compared to milliampere-second settings and radiation dose. Objective noise measurements were assessed. Noise measurements in patients were also performed to verify the comparabilty of the animal model. Adequate image quality allowing for detailed visualization of the upper urinary tract was obtained when the tube current-time product was decreased to 70 eff. mAs at 120 kV. Image noise did not impair image quality to a relevant degree using these parameters. There was high agreement among the observers (ICC = 0.95). In the animal experiments, reduced-dose MDCTU produced good image quality. A maximum current-time product reduction to 70 eff. mAs at 120 kV (CTDI(vol) = 5.3 mGy) proved to be feasible, thereby offering an advantageous dosage reduction. The study provides a basis for the development of reduced-dose MDCTU protocols in humans.
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Doses de Radiação , Proteção Radiológica/métodos , Tomografia Computadorizada por Raios X/métodos , Urografia/métodos , Animais , Processamento de Imagem Assistida por Computador , Modelos Animais , Variações Dependentes do Observador , Imagens de Fantasmas , Estatísticas não Paramétricas , Suínos , Tomografia Computadorizada por Raios X/efeitos adversos , Urografia/efeitos adversosRESUMO
A calcium-scoring phantom with hydroxyapatite-filled cylindrical holes (0.5 to 4 mm) was used. High-resolution scans were performed for an accuracy baseline. The phantom was mounted to a moving heart phantom. Non-moving data with the implementation of an ECG-signal were acquired for different pitches (0.2/0.3), heart rates (60/80/95 bpm) and collimations (16 x 0.75/16 x 1.5 mm). Images were reconstructed with a cone-beam multi-cycle algorithm at a standard thickness/increment of 3 mm/1.5 mm and the thinnest possible thickness (0.8/0.4 and 2/1). Subsequently, ECG-gated moving calcium-scoring phantom data were acquired. The calcium volume and Agatston score were measured. The temporal resolution and reconstruction cycles were calculated. High-resolution scans determine the calcium volume with a high accuracy (mean overestimation, 0.8%). In the non-moving measurements, the volume underestimation ranged from about 6% (16 x 0.75 mm; 0.8/0.4 mm) to nearly 25% (16 x 1.5 mm; 3/1.5 mm). Moving scans showed increased measurement errors depending on the reconstructed RR interval, collimation, pitch, heart rate and gantry rotation time. Also, a correlation with the temporal resolution could be found. The reliability of calcium-scoring results can be improved with the use of a narrower collimation, a lower pitch and the reconstruction of thinner images, resulting in higher patient doses. The choice of the correct cardiac phase within the RR interval is essential to minimize measurement errors.
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Calcinose/diagnóstico por imagem , Doença das Coronárias/diagnóstico por imagem , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Eletrocardiografia , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos TestesRESUMO
CT urography has emerged as a serious alternative to conventional urography by utilizing the advantages of modern multislice CT techniques for the visualization of the entire upper urinary tract. Several different examination techniques have been developed in multislice CT (MSCT) urography for improving the opacification and distension of the urinary tract. All efforts in performing MSCT urography have to compromise between the best possible image quality and a reasonably low radiation exposure. Initial low-dose examination protocols are already available. Operating modern MSCT urography properly is not difficult, but it presupposes basic knowledge on the variety of current MSCT urography techniques, including such issues as present-day indications, split-bolus injection, compression, saline infusion, low-dose diuretic administration, hybrid scanning, timing of the acquisition delay, examination protocols, postprocessing, image analysis, and radiation exposure. This article is not intended to provide guidelines of how to conduct MSCT urography, but everyone will be able to understand the functionality of several robust operating MSCT urography techniques, which helps making an individual selection for the clinical practice. In the near future, systematic studies are awaited evaluating the morphologic and diagnostic accuracy of MSCT urography regarding diverse urinary tract disorders.
Assuntos
Tomografia Computadorizada por Raios X/métodos , Urografia/métodos , Doenças Urológicas/diagnóstico por imagem , Meios de Contraste , Diagnóstico Diferencial , Humanos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por ComputadorRESUMO
PURPOSE: To retrospectively analyze the reliability of opacification and image quality of a modified MDCTU examination protocol using furosemide and an individual acquisition delay by low-dose test images MATERIALS AND METHODS: Excretory phase images obtained from 4-row and 16-row MSCTU examinations in 103 patients (69 men, 34 women) were independently reviewed by two radiologists. MDCTUs were performed by using a low-dose furosemide iv injection. No fixed delay for urographic image acquisition was applied. Urographic timing was individually adjusted by performing low-dose test images of the distal ureters to display their current opacification. Image analysis included grading of opacification and image quality of the segmented collecting system. Average urographic delay was calculated. Stratified comparisons of mean scores were assessed. Interobserver kappa values were calculated. RESULTS: Calculated median scan delay for patients with normal creatine levels (n = 92) was 420 sec (mean 453 sec; SD, 121 sec). The median number of acquired test images was 2 (range 1-6 images). The analysis of opacification demonstrated that 97% of the ICS, 89% of the proximal, 86% of the middle, and 81% of the distal ureter segments showed opacification greater than 90%. 7.8% of the distal ureteral segments could not be visualized. Statistics did not show significant differences of opacification between proximal, middle, and distal ureteral segments (P > 0.05). Overall image quality of MSCTU showed to be high when latest test images indicated homogeneous bilateral contrasted ureters (Pearson correlation coefficient r= 0.81). Interobserver kappa values were 0.8 and 0.78. CONCLUSION: Furosemide and scan delay timing by means of test images for MDCTU proved to be a reliable procedure to reach improved opacification of the upper urinary tract. It features the individual adaption of MDCTU to the excretory rate of the kidneys.
Assuntos
Diuréticos , Furosemida , Nefropatias/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Urografia/métodos , Doenças Urológicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de TempoRESUMO
To characterize the peri-infarction zone using T2-weighted (T2w) magnetic resonance imaging (MRI) and infarct size on delayed enhancement (DE) MRI in patients with acute myocardial infarction (AMI). In 65 patients, short-axis T2w and DE MRI images were acquired 5 +/- 3 d after AMI. The MRI was analyzed using a threshold method defining infarct size on DE MRI and edema on T2w MRI as areas with signal intensity larger than +2 SD above remote normal myocardium. The peri-infarction zone was calculated as the difference between the size of edema and the infarct size. The size of edema on T2w MRI (31.3 +/- 13.4% of LV area) was larger than the infarct size on DE MRI (20.3 +/- 10.4% of LV area, p< 0.0001). The size of the peri-infarction zone was 11.0 +/- 10.0% of the LV area. Good correlation was found between infarct size on DE MRI and peak creatine kinase (CK) isoenzyme MB (r = 0.65, p< 0.0001), but there was no correlation between the size of the peri-infarction zone and CK MB (r = 0.05, p = 0.67). The peri-infarction zone was larger in patients with an infarct size <28% of the LV area (12.6 +/- 10.0% LV area) compared with patients with an infarct size > or =28% of the LV area (6.7 +/- 9.0% of the LV area, p< 0.05). The peri-infarction zone does not correlate with enzymatic parameters of infarct size and is substantially larger in small infarcts, indicating viable myocardium.
Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/patologia , Adulto , Idoso , Meios de Contraste , Edema/diagnóstico , Feminino , Gadolínio DTPA , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Adult stem cells are promising for the development of novel therapies in regenerative medicine. Acute renal failure (ARF) remains a frequent clinical complication, associated with an unacceptably high mortality rate, in large part due to the ineffectiveness of currently available therapies. The aim of this study was, therefore, to evaluate the therapeutic effectiveness of bone marrow-derived mesenchymal stem cells in a rat model of ischemia/reperfusion (I/R) ARF. METHODS: We used a common I/R model in rats to induce ARF by clamping both renal pedicles for 40 minutes. Mesenchymal stem cells were iron-dextran-labeled for in vivo tracking studies by magnetic resonance imaging (MRI) and kidneys were imaged for mesenchymal stem cells immediately after infusion and at day 3 after ARF. Renal injury was scored on day 3 and cells were additionally tracked by Prussian blue staining. RESULTS: We show in I/R-induced ARF in rats, modeling the most common form of clinical ARF, that infusion of mesenchymal stem cells enhances recovery of renal function. Mesenchymal stem cells were found to be located in the kidney cortex after injection, as demonstrated by MRI. Mesenchymal stem cells-treated animals had both significantly better renal function on days 2 and 3 and better injury scores at day 3 after ARF. Histologically, mesenchymal stem cells were predominantly located in glomerular capillaries, while tubules showed no iron labeling, indicating absent tubular transdifferentiation. CONCLUSION: We conclude that the highly renoprotective capacity of mesenchymal stem cells opens the possibility for a cell-based paradigm shift in the treatment of I/R ARF.
Assuntos
Injúria Renal Aguda/terapia , Traumatismo por Reperfusão/terapia , Transplante de Células-Tronco , Injúria Renal Aguda/patologia , Animais , Corantes , Ferrocianetos , Sobrevivência de Enxerto , Complexo Ferro-Dextran , Rim/patologia , Imageamento por Ressonância Magnética , Masculino , Mesoderma/citologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismo por Reperfusão/patologiaAssuntos
Valva Aórtica/cirurgia , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Imagem Cinética por Ressonância Magnética , Valva Mitral/cirurgia , Deiscência da Ferida Operatória/diagnóstico , Ecocardiografia Transesofagiana , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: We sought to evaluate intraindividually 3 different preparation protocols for achieving improved opacification and anatomic depiction of the upper urinary tract in multisclice computed tomography urography (MSCTU) using a porcine model. MATERIAL AND METHODS: MSCTU was performed in 8 healthy pigs. Each animal underwent 3 MSCT urographies using 3 different preparations before the injection of contrast material: A, intravenous (iv) saline (250 mL); B, iv low-dose furosemide (0.1 mg/kg); and C, iv saline (250 mL) plus iv low-dose furosemide (0.1 mg/kg). Image analysis was performed blinded to the applied protocols and included the evaluation of the opacification and anatomic depiction of the upper urinary tract by means of graded scales. Ureteral distension was determined and density was measured within the collecting system. RESULTS: Furosemide significantly improved both mean opacification scores and mean scores of anatomic depiction compared with the exclusive infusion of saline for MSCTU. There was no significant difference between the application of furosemide and the combination of furosemide plus saline. A significant increase of 25-26% for ureteral distension was found when furosemide was applied. Significant lower mean attenuation values (Hounsfield units) and standard deviation were found within the opacified urine for diuretic-enhanced MSCTU. CONCLUSIONS: Low-dose furosemide injection is superior to saline infusion for achieving optimal enhancement in MSCTU. It is not necessary to combine furosemide and saline infusion. In MSCTU, low-dose furosemide is a simple add-on simplifying image acquisition timing and removing the need for abdominal compression devices.