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Dive into the research topics where Juan Ramón Ayuso is active.

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Featured researches published by Juan Ramón Ayuso.


Hepatology | 2007

Diagnosis of hepatic nodules 20 mm or smaller in cirrhosis: Prospective validation of the noninvasive diagnostic criteria for hepatocellular carcinoma†

Alejandro Forner; Ramon Vilana; Carmen Ayuso; Lluís Bianchi; Manel Solé; Juan Ramón Ayuso; Loreto Boix; Margarita Sala; María Varela; Josep M. Llovet; Concepció Brú; Jordi Bruix

This study prospectively evaluates the accuracy of contrast‐enhanced ultrasound (CEUS) and dynamic magnetic resonance imaging (MRI) for the diagnosis of nodules 20 mm or smaller detected during ultrasound (US) surveillance. We included 89 patients with cirrhosis [median age, 65 years; male 53, hepatitis C virus 68, Child‐Pugh A 80] without prior hepatocellular carcinoma (HCC) in whom US detected a small solitary nodule (mean diameter, 14 mm). Hepatic MRI, CEUS, and fine‐needle biopsy (gold standard) (FNB) were performed at baseline. Non‐HCC cases were followed (median 23 months) by CEUS/3 months and MRI/6 months. FNB was repeated up to 3 times and on detection of change in aspect/size. Intense arterial contrast uptake followed by washout in the delayed/venous phase was registered as conclusive for HCC. Final diagnoses were: HCC (n = 60), cholangiocarcinoma (n = 1), and benign lesions (regenerative/dysplastic nodule, hemangioma, focal nodular hyperplasia) (n = 28). Sex, cirrhosis cause, liver function, and alpha‐fetoprotein (AFP) levels were similar between HCC and non‐HCC groups. HCC patients were older and their nodules significantly larger (P < 0.0001). First biopsy was positive in 42 of 60 HCC patients. Sensitivity, specificity, and positive and negative predictive values of conclusive profile were 61.7%, 96.6%, 97.4%, and 54.9%, for MRI, 51.7%, 93.1%, 93.9%, and 50.9%, for CEUS. Values for coincidental conclusive findings in both techniques were 33.3%, 100%, 100%, and 42%. Thus, diagnosis of HCC 20 mm or smaller can be established without a positive biopsy if both CEUS and MRI are conclusive. However, sensitivity of these noninvasive criteria is 33% and, as occurs with biopsy, absence of a conclusive pattern does not rule out malignancy. These results validate the American Association for the Study of Liver Disease (AASLD) guidelines. (HEPATOLOGY 2007.)


The American Journal of Gastroenterology | 2004

Preoperative Staging and Tumor Resectability Assessment of Pancreatic Cancer: Prospective Study Comparing Endoscopic Ultrasonography, Helical Computed Tomography, Magnetic Resonance Imaging, and Angiography

Antonio Soriano; Antoni Castells; Carmen Ayuso; Juan Ramón Ayuso; Maria Teresa de Caralt; Maria Àngels Ginès; Maria Isabel Real; Rosa Gilabert; Llorenç Quintó; Antoni Trilla; Faust Feu; Xavier Montanyà; Laureano Fernández-Cruz; Salvador Navarro

OBJECTIVES:The objective of this study was to evaluate prospectively the efficacy of different strategies based on endoscopic ultrasonography (EUS), helical computed tomography (CT), magnetic resonance imaging (MRI), and angiography (A) in the staging and tumor resectability assessment of pancreatic cancer.METHODS:All consecutive patients with pancreatic carcinoma judged fit for laparotomy were studied by EUS, CT, MRI, and A. Results of each of the imaging techniques regarding primary tumor, locoregional extension, lymph-node involvement, vascular invasion, distant metastases, tumor TNM stage, and tumor resectability were compared with the surgical findings. Univariate, logistic regression, decision, and cost minimization analyses were performed.RESULTS:Sixty-two patients with pancreatic cancer were included. Helical CT had the highest accuracy in assessing extent of primary tumor (73%), locoregional extension (74%), vascular invasion (83%), distant metastases (88%), tumor TNM stage (46%), and tumor resectability (83%), whereas EUS had the highest accuracy in assessing tumor size (r = 0.85) and lymph node involvement (65%). The decision analysis demonstrated that the best strategy to assess tumor resectability was based on CT or EUS as initial test, followed by the alternative technique in those potentially resectable cases. Cost minimization analysis favored the sequential strategy in which EUS was used as a confirmatory technique in those patients in whom helical CT suggested resectability of the tumor.CONCLUSIONS:Helical CT and EUS are the most useful individual imaging techniques in the staging of pancreatic cancer. In those cases with potentially resectable tumors a sequential approach consisting of helical CT as an initial test and EUS as a confirmatory technique seems to be the most reliable and cost minimization strategy.


Clinical Gastroenterology and Hepatology | 2008

Portal Hypertension–Related Complications After Acute Portal Vein Thrombosis: Impact of Early Anticoagulation

Juan Turnes; Juan Carlos García–Pagán; Mónica Alonso González; Carles Aracil; Jose Luis Calleja; Cristina Ripoll; Juan G. Abraldeṣ; Rafael Bañares; Cándido Villanueva; Agustín Albillos; Juan Ramón Ayuso; Rosa Gilabert; Jaime Bosch

BACKGROUND & AIMS Acute portal vein thrombosis (APVT) is a rare disorder that causes chronic portal hypertension if recanalization is not obtained. However, response to anticoagulation and long-term prognosis of APVT are not well-defined. METHODS Thirty-eight patients diagnosed with APVT between 1995 and 2003 from 5 Spanish referral hospitals, in whom cirrhosis and malignancy were specifically excluded, were included in this retrospective study. The response to anticoagulation therapy and development of portal hypertension-related complications during follow-up were evaluated. RESULTS Mean follow-up was 43 months (range, 6-112 months). Recanalization occurred in 12 of 27 patients receiving anticoagulation versus 0 of 11 patients who did not receive anticoagulation (P = .008). Rates of recanalization were influenced by the precocity of heparin administration and the number of underlying prothrombotic conditions. Follow-up upper endoscopy performed in 29 patients disclosed gastroesophageal varices in 16 (55%). Varices appeared as early as 1 month after APVT. However, in most patients varices were detected in successive endoscopies, mainly during the first year. Two-year actuarial probability of variceal bleeding was 12% and for ascites 16%. Five-year survival was 87%. Mortality was related to the APVT episode in 2 cases and to an underlying hematologic disorder in one. CONCLUSIONS Anticoagulation achieved recanalization in about 40% of patients. Most patients not achieving recanalization will develop gastroesophageal varices during follow-up. However, development of variceal bleeding and ascites is infrequent, and survival is satisfactory.


Journal of Magnetic Resonance Imaging | 2004

MRA is useful as a follow-up technique after endovascular repair of aortic aneurysms with nitinol endoprostheses

Juan Ramón Ayuso; Teresa M. de Caralt; Mario Pagés; Vicente Riambau; Carmen Ayuso; Marcelo Sánchez; Maria Isabel Real; Xavier Montañá

To evaluate whether MR angiography (MRA) is a useful tool for the follow‐up of aortic aneurysms treated with nitinol endoluminal grafts.


American Journal of Roentgenology | 2006

Sonography of Budd-Chiari Syndrome

Xavier Bargalló; Rosa Gilabert; Carlos Nicolau; Juan Carlos García-Pagán; Juan Ramón Ayuso; Concepció Brú

OBJECTIVE The purpose of this pictorial essay is to review the color Doppler sonographic features of Budd-Chari syndrome. CONCLUSION Combining color and spectral data, sonography provides hemodynamic and anatomic information about vessel patency and collateral vessel formation. The diagnosis of Budd-Chari syndrome is based on the involvement of hepatic veins although intrahepatic collateral circulation and dilated caudate veins are also important and frequent signs. Half of the patients will develop regenerative nodules that can simulate hepatocellular carcinoma.


Liver Transplantation | 2004

Preoperative evaluation of biliary anatomy in adult live liver donors with volumetric mangafodipir trisodium enhanced magnetic resonance cholangiography

Juan Ramón Ayuso; Carmen Ayuso; Ernest Bombuy; Carmen De Juan; Josep M. Llovet; Teresa M. de Caralt; Marcel Sánchez; Mario Pagés; Jordi Bruix; Juan Carlos García-Valdecasas

Accurate preoperative depiction of biliary anatomy is not always adequately accomplished by imaging techniques in living donor liver transplantation (LDLT). We present the results of a prospective study designed to evaluate the ability of mangafodipir trisodium (Mn‐DPDP)‐enhanced magnetic resonance (MR) cholangiography (MRC) for this purpose in a series of 25 adult living liver donors (LLDs). We also analyze if a simple or a more complex surgical procedure can be preoperatively suggested for biliary reconstruction in the recipients. Findings on MRC were compared with operative cholangiography (OC). A conventional distribution with a right hepatic duct (RHD) longer than 1 cm anticipated a simple procedure (duct‐to‐duct anastomosis or hepaticojejunostomy [HJ]). A shorter RHD or any variant were predictors of a more complex surgery (bench ductoplasty or multiple anastomoses). Agreement between MRC and OC in assessing the biliary anatomy was measured using the κ statistic, and differences between the kind of surgery predicted at MRC and the biliary anastomosis performed were evaluated with Fishers exact test. Normal variants were present in 16 / 25 donors (64%). MRC was accurate in depicting the pattern of bile duct distribution observed at OC in 22 / 25 (88%) donors (κ = .831), and correctly predicted the complexity of biliary anastomosis in the recipient in 22 / 25 (88%) donors. No significant differences were observed between complexity of biliary surgery proposed at MRC and the final surgery performed (P = .002). In conclusion, Mn‐DPDP‐enhanced MRC is highly accurate in depicting the biliary duct anatomy and can be used preoperatively for surgical planning in LDLT. (Liver Transpl 2004;10:1391–1397.)


Cancer | 2010

Imatinib plus low-dose doxorubicin in patients with advanced gastrointestinal stromal tumors refractory to high-dose imatinib: a phase I-II study by the Spanish Group for Research on Sarcomas.

Joan Maurel; Ana Sofia Martins; Andres Poveda; José Antonio López-Guerrero; R. Cubedo; Antonio Casado; Javier Martinez-Trufero; Juan Ramón Ayuso; Antonio Lopez-Pousa; Xabier García-Albéniz; Xavier Garcia del Muro; Enrique de Alava

In KIT‐expressing Ewing sarcoma cell lines, the addition of doxorubicin to imatinib increases apoptosis, compared with imatinib or doxorubicin alone. On the basis of these in vitro data, the authors conducted a phase 1‐2 trial of doxorubicin with imatinib in patients with gastrointestinal sarcoma tumors refractory to high‐dose imatinib therapy.


European Radiology | 1999

Atypical retroperitoneal fibrosis: MRI findings.

Juan Ramón Ayuso; A. Garcia-Criado; T. M. Caralt; Carmen Ayuso; A. Torras; T. Ribalta

Abstract. A case of retroperitoneal fibrosis with an unusual perirenal involvement diagnosed at MR imaging is reported. Other conditions, such as metastatic disease or lymphoma, may be considered especially when the initial presentation is not typical. Imaging modalities in this condition are discussed.


Radiology | 2012

Evaluation of Abdominal Aortic Aneurysm after Endovascular Repair: Prospective Validation of Contrast-enhanced US with a Second-Generation US Contrast Agent

Rosa Gilabert; Laura Buñesch; Maria Isabel Real; Ángeles García-Criado; Marta Burrel; Juan Ramón Ayuso; Marta Barrufet; Xavier Montañá; Vicenç Riambau

PURPOSE To prospectively assess the accuracy of contrast agent-enhanced (CE) ultrasonography (US) with a second-generation US contrast agent in the detection and classification of endoleaks after endovascular repair of abdominal aortic aneurysms (EVAR), with computed tomographic (CT) angiography as the reference standard. MATERIALS AND METHODS Institutional review board and written informed consent were obtained. Thirty-five patients who underwent EVAR were enrolled in a prospective study that consisted of CT angiography and CE US studies performed at 1- and 6-month follow-up and performed yearly thereafter. CE US was performed after bolus injection of 2.4 mL of sulfur hexafluoride by using equipment with specific software for contrast studies. Angiography was performed in patients who had type II endoleaks with an increase in aneurysm sac size and in patients with type I or III endoleaks. CE US sensitivity, specificity, positive and negative predictive values, and accuracy were determined for endoleak detection, and Cohen κ statistic was used to assess agreement of CE US and CT angiographic findings for endoleak classification. RESULTS A total of 126 CT angiographic and CE US studies were performed. CT angiography depicted 34 endoleaks in 16 patients (type IA, n=1; type IB, n=1; type II inferior mesenteric artery, n=2; type II lumbar artery, n=28; type II complex, inferior mesenteric, and lumbar arteries, n=2). CE US depicted 33 endoleaks. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CE US in endoleak detection were 97%, 100%, 100%, 98%, and 99%, respectively. CE US enabled correct classification of 26 of 33 endoleaks. No clinically important endoleak was missed at CE US. CONCLUSION CE US yields good sensitivity, specificity, and accuracy in endoleak detection, and it might represent a noninvasive tool that can be used in the follow-up of patients who undergo EVAR.


Gastroenterología y Hepatología | 2004

Registro hospitalario de tumoraciones pancreáticas. Experiencia del Hospital Clínic de Barcelona

A. Soriano-Izquierdo; Antoni Castells; Maria Pellise; Carmen Ayuso; Juan Ramón Ayuso; T.M. De Caralt; Gloria Fernández-Esparrach; Ma Gines; Ángeles García-Criado; M. Martín; Joan Maurel; Rosa Miquel; Josep Antoni Bombí; Pere Gascón; A. Biete; Josep M. Piqué; Laureano Fernández-Cruz; Salvador Navarro

Objetivo Describir las caracteristicas de los pacientes incluidos en el registro de tumoraciones pancreaticas del Hospital Clinic de Barcelona. Pacientes y metodo Se ha incluido a todos los pacientes con tumoraciones pancreaticas atendidos desde julio de 1990 a marzo de 2003. Las variables recogidas fueron: edad, sexo, fecha de diagnostico, diagnostico fundamental, diagnostico histologico, tamano, localizacion y estadio del tumor, y tratamiento efectuado. Por otra parte, se ha evaluado la correlacion del estadio tumoral con la edad del paciente, la fecha de diagnostico y la localizacion de la tumoracion. Resultados Durante el periodo de estudio, se ha incluido a 630 pacientes con tumoraciones pancreaticas, lo que supone una incidencia de 60 pacientes/ano. La edad media fue de 66 anos y la relacion varon/mujer, de 1,18:1. Las lesiones malignas de pancreas fueron las mas frecuentes (92%), y el adenocarcinoma ductal pancreatico fue el tipo histologico mas comun (73%). La localizacion mas frecuente fue la cabeza pancreatica (64%). En el 28% de los pacientes el tumor se diagnostico en estadios I y II. El 31% de los pacientes fue resecado, mientras que el 48% no recibio ningun tipo de tratamiento. La relacion enfermedad localizada (estadio I)/diseminada (estadio IV) fue de 0,34. El cociente estadio I/IV aumento con la edad, el diagnostico anterior a 1994 y la localizacion en la cabeza pancreatica. ConclusiOn Los registros hospitalarios de tumores permiten establecer con precision el perfil de la poblacion atendida, lo que puede contribuir a delinear la mejor estrategia diagnostico-terapeutica y ser de utilidad en la investigacion clinica.

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Joan Maurel

University of Barcelona

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Carmen Ayuso

University of Barcelona

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Rosa Miquel

University of Barcelona

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Mario Pagés

University of Barcelona

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Jaime Feliu

Hospital Universitario La Paz

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