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Publicaciones científicas más recientes (desde 2010)

Autores: Prieto, Elena; Garcia-Velloso, Maria Jose; Rodríguez-Fraile, M; et al.
Revista: PHYSICA MEDICA
ISSN 1120-1797  Vol. 46  2018  págs. 134-139
A significant radiation dose reduction of 28.7% was reached. Despite a slight reduction in image quality, the new regime was successfully implemented with readers reporting unchanged clinical confidence
Autores: Marti-Climent, JM; Morán, Verónica; Mota, M. L.; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 45  2018  págs. S733
Autores: Prieto, Elena; Aguilar Redondo, P. B.; Morán, Verónica; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 45  Nº Supl. 1  2018  págs. S312 - S313
Autores: Azcona, Juan Diego; Barbes, B; Morán, Verónica; et al.
Revista: MEDICAL DOSIMETRY
ISSN 0958-3947  Vol. 42  Nº 4  2017  págs. 282 - 288
This study aimed to describe the commissioning of small field size radiosurgery cones in a 6-MV flattening filter free (FFF) beam and report our measured values. Four radiosurgery cones of diameters 5, 10, 12.5, and 15¿mm supplied by Elekta Medical were commissioned in a 6-MV FFF beam from an Elekta Versa linear accelerator. The extraction of a reference signal for measuring small fields in scanning mode is challenging. A transmission chamber was attached to the lower part of the collimators and used for percentage depth dose (PDD) and profile measurements in scanning mode with a stereotactic diode. Tissue-maximum ratios (TMR) and output factors (OF) for all collimators were measured with a stereotactic diode (IBA). TMR and the OF for the largest collimator were also acquired on a polystyrene phantom with a microionization chamber of 0.016¿cm3 volume (PTW Freiburg PinPoint 3D). Measured TMR with diode and PinPoint microionization chamber agreed very well with differences smaller than 1% for depths below 20¿cm, except for the smaller collimator, for which differences were always smaller than 2%. Calculated TMR were significantly different (up to 7%) from measured TMR. OF measured with diode and chamber showed a difference of 3.5%. The use of a transmission chamber allowed the measurement of the small-field dosimetric properties with a simple setup. The commissioning of radiosurgery cones in FFF beams has been performed with essentially the same procedures and recommended ...
Autores: Azorin, J.F.P.; Aguilar Redondo, P. B.; et al.
Revista: PHYSICS IN MEDICINE AND BIOLOGY
ISSN 0031-9155  Vol. 62  Nº 18  2017  págs. N417 - N427
In this study, we present a new procedure for the comparison of two dose matrices by means of a statistical test. A statistical distance is proposed to decide whether the difference between the two matrices is statistically significant. This statistical test is based on the square difference between the experimental and expected gamma matrix results. The expected gamma matrix is calculated by simulating the measurement process. For comparison purposes, the significance level of the test was chosen to give the same statistical significance as 90% of gamma-pass rate. The performance of the statistical distance is checked against 53 VMAT. The power of the presented test was compared using simulations with the 90% gamma-pass rate criteria for two cases in which intentional errors are introduced. In both cases, the test is uniformly more powerful. According to the test, two of the measured plans have a significant difference with calculated matrices, although the gamma pass rate measured was always greater than 90%.
Autores: Marti-Climent, JM; Prieto, Elena; Morán, Verónica; et al.
Revista: EJNMMI RESEARCH
ISSN 2191-219X  Vol. 7  Nº 1  2017  págs. 37
The mean ED for body and brain PET/CT protocols with different radiopharmaceuticals ranged between 4.6 and 20.0 mSv. The major contributor to total ED for body protocols is CT, whereas for brain studies, it is the PET radiopharmaceutical.
Autores: Sancho, Lidia; Rodríguez-Fraile, M; Bilbao, José Ignacio; et al.
Revista: JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY
ISSN 1051-0443  Vol. 28  Nº 11  2017  págs. 1536 - 1542
Purpose:To determine if baseline patient, tumor, and pretreatment evaluation characteristics could help identify patients who require technetium-99m (Tc-99m) macroaggregated albumin Tc-(99m MAA) imaging before selective internal radiation therapy (SIRT). Materials and Methods: In this retrospective analysis, 532 consecutive patients with primary (n = 248) or metastatic (n = 284) liver tumors were evaluated between 2006 and 2015. Variables were compared between patients in whom Tc-99m MAA imaging results contraindicated/modified SIRT administration with yttrium-90 (Y-90) resin microspheres and those who were treated as initially planned. The Tc-99m MAA findings that contraindicated/modified SIRT were a lung shunt fraction (LSF) > 20%, gastrointestinal Tc-99m MAA uptake, or a mismatch between Tc-99m MAA uptake and intrahepatic tumor distribution. Results: LSF > 20% and gastrointestinal MAA uptake were observed in 7.5% and 3.9% of patients, respectively, and 11% presented a mismatch. Presence of a single lesion (odds ratio [OR] = 2.4) and vascular invasion (OR = 5.5) predicted LSF > 20%, and GI MAA uptake was predicted by the presence of liver metastases (OR = 3.7) and Tc-99m MAA injection through the common/proper hepatic artery (OR = 4.7). Vascular invasion (OR = 4.1) was the only predictor of LSF > 20% and/or GI MAA uptake (sensitivity = 49.2%, specificity = 80.3%, negative predictive value = 92.4%). Previous antiangiogenic treatment (OR = 2.4) and presence of a single lesion (OR = 2.6) predicted mismatch. Conclusions: Imaging with Tc-99m MAA is essential in SIRT workup because baseline characteristics may not adequately predict Tc-99m MAA results. Nevertheless, the absence of vascular invasion potentially identifies a group of patients at low risk of SIRT contraindication/modification in whom performing SIRT in a single session (ie, pretreatment evaluation and SIRT on the same day) should be explored.
Autores: Guillen Valderrama, E; Díaz Perdigón, M.; García, Berta; et al.
Revista: REVISTA ESPAÑOLA DE MEDICINA NUCLEAR E IMAGEN MOLECULAR
ISSN 2253-654X  Vol. 36  Nº Supl 1  2017  págs. 16
Autores: Morán, Verónica; Prieto, Elena; García, Berta; et al.
Revista: REVISTA ESPAÑOLA DE MEDICINA NUCLEAR E IMAGEN MOLECULAR
ISSN 2253-654X  Vol. 35  Nº 3  2016  págs. 175-85
It is recommended to increase the distance between the patients during the radiopharmaceutical incorporation and to distribute them according to the diagnostic procedure. Patients should be encouraged to use private instead of public transport. Depending on the number of nuclear medicine outpatients per year attended by a physician, it could be necessary to apply restrictions
Autores: Morán, Verónica; Prieto, Elena; García, Berta; et al.
Revista: REVISTA ESPANOLA DE MEDICINA NUCLEAR E IMAGEN MOLECULAR
ISSN 2253-654X  Vol. 35  Nº 3  2016  págs. 175 - 185
Objectives: The aim of this study was to assess the dose received by members of the public due to close contact with patients undergoing nuclear medicine procedures during radiopharmaceutical incorporation, and comparing it with the emitted radiation dose when the test was complete, in order to establish recommendations. Material and methods: A prospective study was conducted on 194 patients. H*(10) dose rates were measured at 0.1, 0.5, and 1.0 m after the radiopharmaceutical administration, before the image acquisition, and at the end of the nuclear medicine procedure. Effective dose for different close contact scenarios were calculated, according to 95th percentile value (bone scans) and the maximum value (remaining tests). Results: During the radiopharmaceutical incorporation, a person who stays with another injected patient in the same waiting room may receive up to 0.59 mSv. If the patient had a medical appointment, or went to a restaurant or a coffee shop, members of the public could receive 23, 43, and 22 mu Sv, respectively. After finishing the procedure, these doses are reduced by a factor 3. In most of the studies, the use of private instead of public transport may reduce the dose by more than a factor 6. Conclusion: It is recommended to increase the distance between the patients during the radiopharmaceutical incorporation and to distribute them according to the diagnostic procedure. Patients should be encouraged to use private instead of public transport. Depending on the number of nuclear medicine outpatients per year attended by a physician, it could be necessary to apply restrictions.
Autores: García, Berta; Morales, María Isabel; Guillen Valderrama, E; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 43  Nº Supl.1.  2016  págs. S127 - S127
Autores: Sancho, Lidia; Rodríguez-Fraile, M; Prieto, Elena; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 43  Nº Suppl. 1  2016  págs. S12 - S12
Autores: Prieto, Elena; Morán, Verónica; García, Berta; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 43  Nº Supl.1  2016  págs. S528 - S528
Autores: Morán, Verónica; Prieto, Elena; Zubiria, A.; et al.
Revista: EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
ISSN 1619-7070  Vol. 43  Nº Supl 1  2016  págs. S410
Autores: Prieto, Elena; Marti-Climent, JM; Morán, Verónica; et al.
Revista: PHYSICA MEDICA
ISSN 1120-1797  Vol. 31  Nº 8  2015  págs. 948-955
Optimization of reconstruction algorithm and parameters has been performed to take particular advantage of the last generation PET scanner, recommending specific settings for different brain PET radiotracers.
Autores: Sancho, Lidia; Morán, Verónica; et al.
Revista: REVISTA ESPAÑOLA DE MEDICINA NUCLEAR E IMAGEN MOLECULAR
ISSN 2253-8070  Vol. 34  Nº Supl. 1  2015  págs. 59
La evaluación clínica del PET de amiloide con 18 F-florbetapir no se afecta por el tipo de equipo, aunque los de nueva generación reducen el número de casos dudosos. Para el seguimiento, los estudios deben ser adquiridos en un tiempo de adquisición similar. Estos hallazgos son relevantes para los ensayos de posibles nuevos fármacos anti-amiloid
Autores: Marti-Climent, JM; Collantes M; Prieto, Elena; et al.
Revista: RADIOPROTECCION
ISSN 1133-1747  Vol. 79  2014  págs. 26 - 36