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Dive into the research topics where E.R. Alfonso is active.

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Featured researches published by E.R. Alfonso.


CardioVascular and Interventional Radiology | 2001

Animal experience in the Günther Tulip retrievable inferior vena cava filter.

M.A. de Gregorio; M. J. Gimeno; Ricardo Tobío; Fernando Lostalé; Antonio Mainar; J. M. Beltran; Blanca Madariaga; E.R. Alfonso; J. Medrano; Américo Viloria

AbstractPurpose: To assess the retrievability of the Gunther Tulip temporary inferior vena cava filter from a technical viewpoint, and consider the histopathologic changes that occur at the anchoring site of the filter prongs to the vein endothelium in Landrace pigs. Methods: Twenty-two Gunther Tulip retrievable filters were inserted in 22 experimental Landrace pigs via the jugular vein. Device implantation time was 0, 3, 7, 12, 14, 15, 16, 20, 30, 35 and 56 days. Study subjects were divided into two groups. In one group the filter was retrieved percutaneously via the jugular vein whereas in the other group it was removed surgically. The specimens obtained (vena cava and filter) were histopathologically examined. Prior to filter retrieval, a venacavography was obtained in all cases. Degree of retrieval difficulty was rated as follows: no difficulty (N), slight (S), mild (M), high (H) and unretrievable (U). Results: Of the 22 implanted filters, 11 should have been removed percutaneously but this was impossible in three cases (U). In four cases the device was retrieved with no difficulty (N); in two cases the degree of difficulty was mild (M) and in other two it was high (H) and slight (S) respectively. Retrieval difficulties were observed after 16 days. Starting from day 20, there was evidence of fibrosis with thick intimal proliferation and total filter prong involvement, which accounts for the difficulty in retrieving the device. Conclusions: It is advisable not to exceed a filter retrieval time of 16 days in view of the fibrotic changes reported. It might be necessary to perform a larger study with more animals and with retrieval times between 14 and 20 days.


European Radiology | 1997

Radiation myelopathy in over-irradiated patients: MR imaging findings

E.R. Alfonso; M.A. de Gregorio; P. Mateo; R. Escó; N. Bascón; F. Morales; R. Bellosta; P. López; M. J. Gimeno; M. Roca; José Lucio Villavieja

Abstract. The objective of this work is to report the MRI findings in patients with radiation myelopathy due to accidental local over-irradiation syndrome. Eight patients (seven males and one female) were suffering from over-irradiation syndrome as a result of treatments from a malfunctioning linear electron accelerator. The mean accidental estimated dose was 136 Gy delivered to the “open-neck” (seven cases) and to the thoracic wall (one case), during a mean of 5.4 sessions (range 1–9 sessions). Paresthesia and weakness in the upper extremities were the earliest symptoms (87.5 %), with evolution to paralysis in all patients. No patient is alive (mean survival time 64 days). In all cases MRI was negative for neurologic lesions in the acute phase ( < 90 days from irradiation; Radiation Therapy Oncology Group scoring system). Late signs of radiation myelitis manifested as high-intensity signals on T2-weighted images in three patients, and as Gd-DTPA enhancement of T1-weighted images in one case. Autopsies performed on four patients who died in acute phase showed morphologic alterations in white matter: edema in 75 %, and necrosis and glial reaction as well as obliterative vasculitis in all cases. In cases of over-irradiation, MRI may be normal in acute phase even if the patients have severe neurologic deficit, as positive MRI findings appear only in delayed radiation myelitis.


European Radiology | 1996

Subcutaneous ports in the radiology suite: an effective and safe procedure for care in cancer patients

M.A. de Gregorio; José M. Miguelena; José Antonio Fernández; C. de Gregorio; A. Tres; E.R. Alfonso

The purpose of the study is to present our experience and compare the results of the three types of ports used as a central venous access and performed in the radiology suite. Between March 1989 and November 1993 we performed 288 implantations (100 Implantofix Seldinger, 100 plastic Hickman port, and 88 stainless steel Port-a-cath) for chemotherapeutic treatment on the same number of patients diagnosed as having cancer. In all cases access was obtained via a subclavian vein (the left one in 185 cases and the right one in 103). All the system ports were implanted in the radiology suite. In all cases the procedure was successfully performed. Complications occurred in 26.3% of cases, most notably thrombosis in 13 cases (4.5%) and infection in 12 cases (4.1%). Duration of the port systems placement varied between 17 and 1467 days (a mean of 315 days). A total of 133 systems have been removed to date, 80 (60.%) due to termination of chemotherapy, and 53(40%) for treatment of complications. Significant differences (complications and port duration time) were not observed between the three types of reservoir used. Subcutaneous ports are safe, comfortable, and effective devices for central venous access.


Journal of Vascular and Interventional Radiology | 2004

Retrievability of Uncoated Versus Paclitaxel-coated Günther-Tulip IVC Filters in an Animal Model

Miguel Ángel de Gregorio; M. J. Gimeno; Fernando Lostalé; Pablo Iñigo; María Consuelo Artigas; Américo Viloria; E.R. Alfonso; Horacio D'Agostino

PURPOSE To compare in a pilot study, the retrievability and inferior vena cava (IVC) wall reaction elicited by uncoated and paclitaxel-coated Günther-Tulip filters in the animal model. MATERIALS AND METHODS Three groups with five pigs each underwent infrarenal IVC implantation of Günther-Tulip filters. Paclitaxel-coated filters were used in Groups A and B and uncoated filters were used in Group C. Filters were removed at 14, 19, 22, 26, and 30 days after implantation. A laparotomy was performed to remove filters from animals in group A and filters from animals in groups B and C that could not be retrieved via the right transjugular approach. Filter-induced venous wall changes were evaluated by examination of IVC venography, feasibility of filter removal at different implantation times, and laparotomy and microscopic findings. Feasibility of filter retrieval and venous wall changes were correlated. RESULTS IVC cavography showed no abnormality. Filters in animals in group B were uneventfully removed by a right jugular approach. Uncoated filter removal was not feasible in three of five animals in group C (19, 22, and 26 days). Microscopically, animals in group A had absent filter-induced IVC wall changes at 14, 19, 22, and 26 days and minimal changes at 30 days post implantation; animals in group B had absent filter-induced IVC wall changes at 14, 19, and 22 days and minimal changes at 26 and 30 days; animals in group C had moderate filter-induced IVC wall changes at 14 days and severe changes at 19, 22, 26, and 30 days. CONCLUSIONS This pilot study suggests that endothelial reaction to the presence of IVC filters in the porcine model is diminished by addition of paclitaxel coating to these filters. Further studies are necessary to substantiate these results.


Archivos De Bronconeumologia | 2006

Endovascular Treatment of Massive Hemoptysis by Bronchial Artery Embolization: Short-Term and Long-Term Follow-Up Over a 15-Year Period

M.A. de Gregorio; J. Medrano; Antonio Mainar; E.R. Alfonso; M. Rengel

OBJECTIVE To present our experience of using arterial embolization for the endovascular treatment of massive hemoptysis along with the results of follow-up over a 15-year period. PATIENTS AND METHODS A total of 401 patients with hemoptysis were referred to the minimally invasive surgery unit of the Hospital Universitario Lozano Blesa de Zaragoza between April 1989 and September 2004 for diagnosis and possible endovascular treatment. Of those patients, 314 met criteria for massive hemoptysis and treatment was attempted using embolization in 287 (91.4%). The most common cause of hemoptysis was bronchiectasis (n=99, 31.5%), followed by lesions due to tuberculosis (n=57, 18.1%) and chronic bronchitis (n=47, 14.9%). RESULTS Angiography of the bronchial arteries provided evidence to account for the hemoptysis in 287 patients (91.4%). The affected arteries were satisfactorily embolized in 281 (97.9%). Endovascular treatment was clinically successful in 256 of those patients (91.1%). Embolization had to be repeated during the hospital stay in 19 patients (6.7%) and was effective in 52.6% of those cases. The 6 patients in whom embolization was not satisfactory underwent thoracotomy. The mean follow-up in 201 patients (71.5%) was 2372.5 days (range, 61-5475 days). Eighty patients (28.4%) were lost to follow-up for various reasons and at different points. Recurrence of hemoptysis occurred on 1 or more occasions in 45 patients (22.3%) but only 21 (10.4%) required repeat embolization. Minor complications that did not require treatment were observed in 88 patients (28.0%). CONCLUSIONS Embolization of bronchial arteries is a nonsurgical treatment that is safe and effective in patients with massive hemoptysis.


CardioVascular and Interventional Radiology | 1999

Transcatheter intracavitary fibrinolysis of loculated pleural effusions: experience in 102 patients.

Miguel Ángel de Gregorio; C. Ruiz; E.R. Alfonso; José Antonio Fernández; Joaquín Medrano; I. Ariño

AbstractPurpose: To assess the efficacy of intrapleural urokinase instillation through smll-caliber catheters for the treatment of loculate and/or septate effusions. Methods: We inserted small-caliber catheters (8.2 Fr) in 102 patients with septate and/or loculate pleural effusions using ultrasonographic guidance. Urokinase (100,000 IU/2 hr, 3 times a day) was instilled through the catheter until the effusion resolved and D-dimer levels were <500 ng/ml. Patients were enrolled regardless of the etiology of the pleural effusion provided there were no contraindications for the use of urokinase. D-dimer levels were determined before and after treatment. Follow-up was performed by chest radiograph and sonography at 1 day, 7 days, and every 30 days thereafter for 6 months. Results: Successful catheter placement was achieved in all cases. The mean time catheters stayed in place was 5.7 days and the mean dose of drug instilled was 690,000 IU. Pleural effusion drainage was complete at the first assessment in all patients. Failure of the treatment, with recurrent effusion at 30 days, occurred in six patients (5.8%). Complete resolution without sequelae was observed in 19 patients (19.6%). In 75 cases (73.5%) resolution was partial, with pleural thickening (>2 mm). Two patients died from unrelated causes within 30 days after catheter placement. Complications were seen in 13 patients (12.74%): hydropneumothorax, nine cases (8.82%); infection of the puncture point, three cases (2.94%); and adverse reaction, one case (0.98%). No further treatment was required. Conclusions: The use of intrapleural fibrinolytic agents delivered through small-caliber catheters for the treatment of loculate and/or septate pleural effusion is a simple, effective, minimally invasive and inexpensive procedure that can prevent sequelae and shorten drainage time.


Seminars in Interventional Radiology | 2004

Colon Stenting: A Review

Miguel Ángel de Gregorio; Antonio Mainar; Juan Rodriguez; E.R. Alfonso; Eloy Tejero; Marcos Herrera; J. Medrano; Horacio D'Agostino

Up to 85% of patients who present with colonic obstruction have a colorectal cancer. Between 7% and 29% of these patients present with total or partial intestinal obstruction. Only 20% of these patients presenting with acute colonic obstruction due to malignancy survive 5 years. Emergent surgical intervention in patients with colonic obstruction is associated with significant morbidity and mortality rates. Only 40% of patients with obstructive carcinoma of the left colon can be treated with surgical resection without the need for a colostomy. The use of a temporary or permanent colostomy has a significant impact on quality of life. The decompressive effect seen with colonic stenting is a durable, simple, and effective palliative treatment of patients with advanced disease. Stent deployment provides an effective solution to acute colonic obstruction and allows surgical treatment of the patient in an elective and more favorable condition. In addition, colonic stenting reduces costs and avoids the need for a colostomy.


European Radiology | 2002

Use of an introducer sheath for colonic stent placement

Miguel Ángel de Gregorio; Antonio Mainar; Eloy Tejero; E.R. Alfonso; M. J. Gimeno; Marcos Herrera

Abstract. We describe a technical modification of Wallstent implantation for the treatment of malignant rectosigmoid and descending colonic obstructions. The modification is the routine placement of an introducer sheath via the rectum before stent implantation in order to straighten the rectosigmoid region. This device facilitates catheter and guide wire manipulations and obtaining specimen biopsies for histopathological studies. The introducer sheath has been used without complications in 21 consecutive patients.


Archivos De Bronconeumologia | 1995

Seguimiento clínico y por medios de imagen a largo plazo de los filtros de vena cava inferior. Estudio transversal

M.A. de Gregorio; E.R. Alfonso; José Antonio Fernández; I. Ariño; J. Medrano; José Lucio Villavieja; Antonio Mainar; P. Rubio

Hemos realizado un estudio transversal con el fin de evaluar los hallazgos morfologicos, incidencias y complicaciones observadas en 77 filtros de vena cava inferior implantados en 75 pacientes desde abril de 1990 hasta enero de 1994. El tiempo de seguimiento de los pacientes oscilo entre los 3 y los 61 meses (media, 38,5 meses), realizando encuesta telefonica, evaluacion clinica, iliocavografia y, en algunos casos, ecografia-Doppler y tomografia computarizada (TC). Los hallazgos observados demostraron trombosis de vena cava en el 38% de los casos, edemas en EE1I en el 63,4% de los casos, angulacion > 15° en 8 pacientes, defecto de apertura en 4 pacientes, fibrosis de vena cava con estenosis en 2 casos y perforacion de vena cava inferior en 3 pacientes. Segun nuestro estudio si bien la incidencia de la trombosis de VCI posfiltro es mas alta que la sospechada habitualmente, la trascendencia clinica resulta irrelevante.


Archivos De Bronconeumologia | 1997

Estado actual y experiencia clínica en el tratamiento de las estenosis traqueobronquiales con prótesis metálicas autoexpandibles

M.A. de Gregorio; J. Medrano; E.R. Alfonso; José Antonio Fernández; C. Ruiz; H. Vallés; F.J. Suarez

La aparicion de una estenosis sintomatica en el arbol bronquial puede provocar a los pacientes una situacion de alto riesgo vital por asfixia. La implantacion de protesis ( stents ) metalicas puede resolver la estenosis de una forma paliativa y aliviar el estado clinico de estos pacientes. Evaluamos la efectividad de las protesis metalicas expandibles como metodo terapeutico en diferentes tipos de estenosis traqueobronquiales. Se han implantado en la sala de radiologia intervencionista (RI), bajo control fluoroscopico y endoscopico, un total de 16 protesis metalicas autoexpandibles tipo Wallstent en 16 pacientes con estenosis traqueobronquiales (12 malignas y 4 benignas). Las protesis fueron ubicadas en el lugar correcto, sin apreciarse complicaciones, obteniendose una mejoria clinica inmediata en todos los pacientes. Tres pacientes con estenosis postintubacion necesitaron tratamiento adicional con laser endoscopico durante el control evolutivo. Todos los pacientes con patologia de origen maligno fallecieron por su enfermedad de base, manteniendose sin sintomatologia traqueal y con su luz permeable. Las protesis metalicas constituyen una alternativa terapeutica paliativa valida en las estenosis traqueobronquiales malignas.

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J. Medrano

University of Zaragoza

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Eloy Tejero

University of Zaragoza

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