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1.
Abdom Radiol (NY) ; 41(9): 1782-92, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27188888

RESUMO

PURPOSE: To evaluate the efficacy of superselective transcatheter arterial embolization (TAE) in the treatment of acute peripancreatic bleeding complications. METHODS: During a 9-year period, 44 patients with acute bleeding of the peripancreatic arteries underwent TAE in our institution. Thirty-eight patients were treated using microcatheters and 6 patients with a diagnostic catheter. Embolic agents included coils (n = 38), polyvinyl alcohol (PVA) particles (n = 2), isobutyl cyanoacrylate (n = 2), coils plus PVA particles (n = 1), and coils plus isobutyl cyanoacrylate (n = 1). Outcome measures included technical success, clinical success, and the rate of complications. RESULTS: Identified bleeding sources included gastroduodenal artery (n = 14), splenic artery (n = 9), pancreaticoduodenal artery (n = 6), common hepatic artery (n = 5), superior mesenteric artery branches (n = 4), proper hepatic artery (n = 3), and dorsal/transverse pancreatic artery (n = 3). Technical success with effective control of active bleeding was achieved in 41/44 patients (93 %). Clinical success attributed to TAE alone was documented in 40/44 patients (91 %). The rate of major complications was 2 % including death in one patient. CONCLUSIONS: Superselective TAE allows effective, minimally invasive control of acute peripancreatic bleeding complications with a low rate of therapeutically relevant complications.


Assuntos
Embolização Terapêutica , Hemorragia , Artéria Hepática , Humanos , Pâncreas , Estudos Retrospectivos , Resultado do Tratamento
2.
Mol Cancer Ther ; 10(6): 1007-17, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21487053

RESUMO

Sorafenib targets the Raf/mitogen-activated protein kinase, VEGF, and platelet-derived growth factor pathways and prolongs survival patients in advanced hepatocellular carcinoma (HCC). Everolimus inhibits the mammalian target of rapamycin, a kinase overactive in HCC. To investigate whether the antitumor effects of these agents are additive, we compared a combined and sequential treatment regimen of everolimus and sorafenib with monotherapy. After hepatic implantation of Morris Hepatoma (MH) cells, rats were randomly allocated to everolimus (5 mg/kg, 2×/week), sorafenib (7.5 mg/kg/d), combined everolimus and sorafenib, sequential sorafenib (2 weeks) then everolimus (3 weeks), or control groups. MRI quantified tumor volumes. Erk1/2, 4E-BP1, and their phosphorylated forms were quantified by immunoblotting. Angiogenesis was assessed in vitro by aortic ring and tube formation assays, and in vivo with Vegf-a mRNA and vascular casts. After 35 days, tumor volumes were reduced by 60%, 85%, and 55%, relative to controls, in everolimus, the combination, and sequential groups, respectively (P < 0.01). Survival was longest in the combination group (P < 0.001). Phosphorylation of 4E-BP1 and Erk1/2 decreased after everolimus and sorafenib, respectively. Angiogenesis decreased after all treatments (P < 0.05), although sorafenib increased Vegf-a mRNA in liver tumors. Vessel sprouting was abundant in control tumors, lower after sorafenib, and absent after the combination. Intussusceptive angiogenic transluminal pillars failed to coalesce after the combination. Combined treatment with everolimus and sorafenib exerts a stronger antitumoral effect on MH tumors than monotherapy. Everolimus retains antitumoral properties when administered sequentially after sorafenib. This supports the clinical use of everolimus in HCC, both in combination with sorafenib or after sorafenib.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzenossulfonatos/farmacologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Piridinas/farmacologia , Sirolimo/análogos & derivados , Inibidores da Angiogênese/farmacologia , Animais , Benzenossulfonatos/administração & dosagem , Proteínas de Transporte/metabolismo , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Everolimo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neovascularização Patológica/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia , Fosfoproteínas/metabolismo , Piridinas/administração & dosagem , Distribuição Aleatória , Ratos , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Sorafenibe , Carga Tumoral/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Radiology ; 257(3): 810-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21084415

RESUMO

PURPOSE: To evaluate diffusion-weighted magnetic resonance (MR) imaging of the human placenta in fetuses with and fetuses without intrauterine growth restriction (IUGR) who were suspected of having placental insufficiency. MATERIALS AND METHODS: The study was approved by the local ethics committee, and written informed consent was obtained. The authors retrospectively evaluated 1.5-T fetal MR images from 102 singleton pregnancies (mean gestation ± standard deviation, 29 weeks ± 5; range, 21-41 weeks). Morphologic and diffusion-weighted MR imaging were performed. A region of interest analysis of the apparent diffusion coefficient (ADC) of the placenta was independently performed by two observers who were blinded to clinical data and outcome. Placental insufficiency was diagnosed if flattening of the growth curve was detected at obstetric ultrasonography (US), if the birth weight was in the 10th percentile or less, or if fetal weight estimated with US was below the 10th percentile. Abnormal findings at Doppler US of the umbilical artery and histopathologic examination of specimens from the placenta were recorded. The ADCs in fetuses with placental insufficiency were compared with those in fetuses of the same gestational age without placental insufficiency and tested for normal distribution. The t tests and Pearson correlation coefficients were used to compare these results at 5% levels of significance. RESULTS: Thirty-three of the 102 pregnancies were ultimately categorized as having an insufficient placenta. MR imaging depicted morphologic changes (eg, infarction or bleeding) in 27 fetuses. Placental dysfunction was suspected in 33 fetuses at diffusion-weighted imaging (mean ADC, 146.4 sec/mm(2) ± 10.63 for fetuses with placental insufficiency vs 177.1 sec/mm(2) ± 18.90 for fetuses without placental insufficiency; P < .01, with one false-positive case). The use of diffusion-weighted imaging in addition to US increased sensitivity for the detection of placental insufficiency from 73% to 100%, increased accuracy from 91% to 99%, and preserved specificity at 99%. CONCLUSION: Placental dysfunction associated with growth restriction is associated with restricted diffusion and reduced ADC. A decreased ADC used as an early marker of placental damage might be indicative of pregnancy complications such as IUGR. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10092283/-/DC1.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Insuficiência Placentária/diagnóstico , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Estatísticas não Paramétricas , Ultrassonografia Pré-Natal
4.
Oncologist ; 15(11): 1198-204, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21036880

RESUMO

BACKGROUND AND AIM: It is unknown whether sorafenib can be combined with transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma. This study assesses the safety and tolerability of a continuous regimen of sorafenib combined with TACE. METHODS: This was an open-label phase I study testing a continuous administration of sorafenib (dose escalation from 200 mg twice daily [bid] to 400 mg bid) starting 7 days prior to TACE with doxorubicin (50 mg). RESULTS: Twenty-one patients were screened and 14 received sorafenib combined with TACE. Because there were no dose-limiting toxicities in the first three patients who received sorafenib at a dose of 200 mg bid, subsequent patients received 400 mg bid. Twenty-seven procedures were performed (median, two per patient) and two local therapy-related severe adverse events occurred. The median duration of sorafenib therapy was 246 days (range, 14-547 days). Sorafenib-related adverse events of grade ≥3 were hand-foot skin reaction (n = 3), weight loss (n = 2), diarrhea (n = 1), abdominal pain (n = 1), and thrombocytopenia (n = 3). After treatment with sorafenib and TACE, there was a significant decrease in the concentration of plasma vascular endothelial growth factor (VEGF) from 93 ng/l to 67 ng/l. CONCLUSIONS: Continuous administration of sorafenib at a dose of 400 mg bid combined with TACE was tolerable. The adverse event profile of this regimen was comparable with that of sorafenib monotherapy with the exception of thrombocytopenia, which may be more frequent. There were no increases in the circulating VEGF levels after TACE with this combined regimen. (Swiss Association for the Study of the Liver study number 25; ClinicalTrials.gov trial identifier, NCT00478374).


Assuntos
Antineoplásicos/administração & dosagem , Benzenossulfonatos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/terapia , Piridinas/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos Antineoplásicos , Benzenossulfonatos/efeitos adversos , Benzenossulfonatos/uso terapêutico , Cateteres de Demora , Terapia Combinada , Doxorrubicina/uso terapêutico , Humanos , Mitomicina/uso terapêutico , Niacinamida/análogos & derivados , Compostos de Fenilureia , Piridinas/efeitos adversos , Piridinas/uso terapêutico , Sorafenibe , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangue
5.
Radiology ; 253(3): 879-90, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19864508

RESUMO

PURPOSE: To prospectively compare the diagnostic accuracy of steady-state, high-spatial-resolution magnetic resonance (MR) angiography of the lower leg, performed with a blood pool contrast agent, with selective digital subtraction angiography (DSA) as the reference standard in patients with symptomatic peripheral arterial disease. MATERIALS AND METHODS: Local ethics committee approval and written informed consent were obtained. In a nonrandomized trial, selective DSA and MR angiography were performed at 3.0 T with a blood pool contrast agent on 22 calves in 20 patients (mean age, 69.4 years +/- 11.3 [standard deviation]), 16 men (mean age, 67.8 years +/- 12.4) and four women (mean age, 75.6 years +/- 3.6 years), to evaluate 352 arterial segments. DSA and MR angiography were performed within 24 hours of each other and directly compared by three experienced, blinded radiologists by using high-spatial-resolution steady-state MR angiograms. Consensus reading for both DSA and MR angiography served as the reference standard. RESULTS: MR angiography was successful and occurred without serious adverse events in all patients. Seven significantly stenosed and 40 occluded segments were rated equally in both modalities. In three cases, the tibial arteries were shown to be occluded or significantly stenosed at DSA but appeared normal or significantly stenosed at MR angiography. The respective average segment sensitivity, specificity, and accuracy were 98.3% (59 of 60), 98% (113.7 of 116), and 98.1% (172.7 of 176) for DSA and 100% (60 of 60), 100% (116 of 116), and 100% (176 of 176) for MR angiography. Steady-state MR angiography was especially useful for the distal peroneal artery and the proximal anterior tibial artery. CONCLUSION: MR angiography performed with blood pool agents has an accuracy comparable with that of selective DSA in the lower leg but with less risk involved. Steady-state imaging performed with blood pool agents facilitates evaluation of MR angiography of infrapopliteal arteries.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Gadolínio , Perna (Membro)/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Compostos Organometálicos , Doenças Vasculares Periféricas/diagnóstico , Artéria Poplítea/patologia , Adulto , Idoso , Análise de Variância , Angiografia Digital , Arteriopatias Oclusivas/patologia , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/patologia , Estudos Prospectivos , Sensibilidade e Especificidade , Estatísticas não Paramétricas
6.
Invest Radiol ; 43(8): 580-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18648258

RESUMO

OBJECTIVES: To assess magnetic resonance (MR)-colonography (MRC) for detection of colorectal lesions using two different T1w three-dimensional (3D)-gradient-recalled echo (GRE)-sequences and integrated parallel data acquisition (iPAT) at a 3.0 Tesla MR-unit. MATERIALS AND METHODS: In this prospective study, 34 symptomatic patients underwent dark lumen MRC at a 3.0 Tesla unit before conventional colonoscopy (CC). After colon distension with tap water, 2 high-resolution T1w 3D-GRE [3-dimensional fast low angle shot (3D-FLASH), iPAT factor 2 and 3D-volumetric interpolated breathhold examination (VIBE), iPAT 3] sequences were acquired without and after bolus injection of gadolinium. Prospective evaluation of MRC was performed. Image quality of the different sequences was assessed qualitatively and quantitatively. The findings of the same day CC served as standard of reference. RESULTS: MRC identified all polyps >5 mm (16 of 16) in size and all carcinomas (4 of 4) correctly. Fifty percent of the small polyps 0.6). CONCLUSIONS: MRC using 3D-GRE-sequences and iPAT is feasible at 3.0 T-systems. The high-resolution 3D-FLASH was slightly preferred over the 3D-VIBE because of better image quality, although both used sequences showed no statistical significant difference.


Assuntos
Colo/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Processamento Eletrônico de Dados , Feminino , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade
7.
Magn Reson Imaging Clin N Am ; 15(3): 395-402, vii, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17893059

RESUMO

MR colonography is a powerful noninvasive method to image colorectal masses and inflammatory bowel disease. This article describes current techniques of MR colonography and compares its implementation at 1.5T and 3T.


Assuntos
Doenças do Colo/diagnóstico , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Artefatos , Catárticos , Imagem Ecoplanar/métodos , Humanos , Aumento da Imagem/instrumentação , Imageamento Tridimensional/métodos , Doenças Inflamatórias Intestinais/diagnóstico , Imageamento por Ressonância Magnética/instrumentação
8.
Curr Gastroenterol Rep ; 6(5): 389-94, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15341715

RESUMO

Colorectal carcinoma is still the second leading cause of cancer-related death, although it arises mostly from benign adenomas. Numerous screening methods are available, but none of them is accepted as ideal. Ultrafast three-dimensional data sets acquired by cross-sectional imaging modalities (CT or magnetic resonance ) in combination with new post-processing modes, known as virtual colonoscopy, have led to a new discussion of screening tests for colorectal cancer. Recently published results indicate a high sensitivity for CT colonography and for MR-based colonography (MRC), with detection rates of greater than 90% for colorectal lesions greater than 10 mm in size. Three-dimensional data acquisition for MRC is performed in less than 1 minute, and no severe complications have been reported. The main advantages of MRC are the lack of ionizing radiation, the low risk of the procedure, and low patient discomfort. MRC has become an attractive diagnostic procedure for colorectal lesions that can also be used as a screening method.


Assuntos
Neoplasias Colorretais/diagnóstico , Colonoscopia/métodos , Humanos , Imageamento por Ressonância Magnética/métodos
9.
Eur Radiol ; 14(12): 2311-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15322808

RESUMO

The purpose of the study was to assess the diagnostic performance of MR cystography with virtual cystoscopic and multiplanar reconstructions for detection of malignant bladder tumors. Thirty-two patients with 43 bladder tumors previously confirmed by cystoscopy (mean size 2.5 cm; 0.4-9.1 cm;) were examined at 1.5 T with a three-dimensional T2-weighted turbo spin echo sequence (TR=2911 ms, TE=500 ms, echo train length 256). Virtual cystoscopic reconstructions (VC) and multiplanar reconstructions (MPR) were obtained and analyzed separately by three radiologists without knowledge of the tumor location. Intraoperative or cystoscopic findings served as standard of reference. Sensitivities and specificities were calculated using a receiver-operating characteristic analysis with five levels of confidence. Area-under-curve values were similar for MPRs (0.952), VC (0.932) and the combination of both methods (0.954). Optimal sensitivity was 92.3% for MPR and 90.7% for VC, respectively, with a specificity of 91.1% for MPR and 90.4% for VC. The combination of MPR and VC resulted in a sensitivity of 90.7% and specificity of 94.0%. MR cystography is a promising, completely non-invasive technique for the detection of bladder lesions with a high diagnostic performance.


Assuntos
Carcinoma de Células de Transição/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/diagnóstico por imagem , Cistoscopia/métodos , Imagem Ecoplanar/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Radiografia , Sensibilidade e Especificidade , Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/diagnóstico por imagem
10.
Top Magn Reson Imaging ; 13(6): 427-34, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12478022

RESUMO

The high incidence of colorectal carcinoma and the fact that colorectal cancer mostly arises from benign adenomas have led to recommendations for screening programs. The introduction of ultrafast three-dimensional datasets acquired by cross-sectional imaging modalities (computed tomography or magnetic resonance imaging) in combination with new postprocessing modes, known as virtual endoscopy, has led to new discussion on the recommendation of screening tests for colorectal cancer. Published results have indicated a high sensitivity for computed tomographic colonography and magnetic resonance-based colonography. Both techniques currently must be combined with colon cleansing. Three-dimensional data acquisition for magnetic resonance-based colonography is less than 1 minute using three-dimensional gradient-echo sequences. The lack of ionizing radiation, the low risk and discomfort to patients, and new techniques of minimized patient preparation make this magnetic resonance technique an attractive diagnostic procedure for colorectal lesions, with many aspects for use as a screening method.


Assuntos
Neoplasias Colorretais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Programas de Rastreamento/métodos , Colonoscopia/métodos , Neoplasias Colorretais/epidemiologia , Meios de Contraste , Humanos , Imageamento Tridimensional , Fatores de Risco
11.
Eur J Radiol ; 42(1): 74-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12039025

RESUMO

OBJECTIVE: Clinical evaluation of computed tomography (CT) fluoroscopy and comparison with conventional CT guidance for monitoring of percutaneous pulmonary biopsy procedures. METHODS: Twenty CT-guided pulmonary biopsy procedures were conducted. The interventions have prospectively been performed either with CT fluoroscopy or with conventional CT guidance. About 120 kV and 50 mA with a frame-rate of eight images per second were used for CT fluoroscopy. Number of pleural needle passages, procedure times, radiation doses and histologic results were analyzed separately for both methods. RESULTS: Compared with conventional CT guidance, CT fluoroscopy was associated with less pleural needle passages (1.8+/-0.6 vs. 1.1+/-0.3; P=0.003, t-test) and procedure times were shorter than for conventional CT guidance (12.7+/-2.2 min vs. 26.7+/-16.4 min; P=0.02). Analysis of estimated patient related radiation exposure and histologic outcome showed no significant difference between conventional and fluoroscopic CT-guided procedures (P>0.05). CONCLUSION: CT fluoroscopy facilitates guidance of percutaneous pulmonary biopsy procedures. Compared with conventional CT assistance, procedure times are decreased and less pleural needle passages are required. While patient-related radiation exposure is similar, operator-related radiation exposure remains a disadvantage associated with CT fluoroscopy.


Assuntos
Biópsia/métodos , Fluoroscopia , Neoplasias Pulmonares/patologia , Pulmão/patologia , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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