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1.
Radiat Oncol ; 7: 211, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23241224

RESUMEN

BACKGROUND: This study investigates the use of TomoDirect™ 3DCRT for whole breast adjuvant radiotherapy (AWBRT) that represents a very attractive treatment opportunity, mainly for radiotherapy departments without conventional Linacs and only equipped with helical tomotherapy units. METHODS: Plans were created for 17 breast cancer patients using TomoDirect in 3DCRT and IMRT modality and field-in-field 3DCRT planning (FIF) and compared in terms of PTV coverage, overdosage, homogeneity, conformality and dose to OARs. The possibility to define patient-class solutions for TD-3DCRT employment was investigated, correlating OARs dose constraints to patient specific anatomic parameters. RESULTS: TD-3DCRT showed PTV coverage and homogeneity significantly higher than TD-IMRT and FIF. PTV conformality was significantly better for FIF, while no differences were found between TD-3DCRT and TD-IMRT. TD-3DCRT showed mean values of the OARs dosimetric endpoints significantly higher than TD-IMRT; with respect to FIF, TD-3DCRT showed values significantly higher for lung V(20Gy), mean heart dose and V(25Gy), while contralateral lung maximum dose and contralateral breast mean dose resulted significantly lower. The Central Lung Distance (CLD) and the maximal Heart Distance (HD) resulted as useful clinical tools to predict the opportunity to employ TD-3DCRT: positive correlations were found between CLD and both V(20Gy) and mean lung dose and between HD and both V25Gy and the mean heart dose. TD-3DCRT showed a significantly shorter mean beam-on time than TD-IMRT. CONCLUSIONS: The present study showed that TD-3DCRT and TD-IMRT are two feasible and dosimetrically acceptable treatment approach for AWBRT, with an optimal PTV coverage and adequate OARs sparing. Some concerns might be raised in terms of dose to organs at risks if TD-3DCRT is applied to a general population. A correct patients clusterization according to simple quantitative anatomic measures, would help to correctly allocate patients to the appropriate treatment planning strategy in terms of target coverage, but also of normal tissue sparing.


Asunto(s)
Neoplasias de la Mama/radioterapia , Imagenología Tridimensional/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Anciano , Relación Dosis-Respuesta en la Radiación , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Proyectos Piloto , Dosificación Radioterapéutica , Radioterapia Adyuvante , Análisis de Regresión , Tomografía Computarizada Espiral
2.
J Vasc Interv Radiol ; 23(12): 1665-1675.e2, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23177114

RESUMEN

PURPOSE: To investigate the exposure parameters, effective dose, frequency, and collective dose for interventional radiology (IR) procedures performed at a single institution during a 9-year period. MATERIALS AND METHODS: According to the anatomic region imaged, seven diagnostic and 16 therapeutic IR procedures performed between 2002 and 2010 were retrospectively investigated with regard to exposure setting parameters and frequency. Dose-area products (DAPs), cumulative doses (CDs), and irradiation time values were analyzed on a sample of 1,100 examinations. DAP distributions (median, mean, and percentiles) were adjunctively determined by using bootstrap resampling in PCXMC software to estimate patient effective dose. Data provided by the Radiological Information System allowed collective effective and per-capita doses to obtained. RESULTS: The exposure parameters showed widespread variability. The median DAP values for pelvic arteriography and pelvic arterial angioplasty/stent placement were 10,015 and 19,424 cGy·cm(2), respectively. For the 23 procedures studied, the estimated average per-procedure effective dose ranged from 0.34 to 104.9 mSv. The pelvis (37%) was the region most often imaged in diagnostic procedures, and angioplasty/stent treatment of vessels was the most frequently performed therapeutic procedure (44%). During the study period, IR procedures increased in frequency (+137%), with a consequent increase in the per-capita dose (0.172 to 0.461 mSv) and collective dose (21 to 58 man-Sv/y). CONCLUSIONS: A comprehensive Monte Carlo-aided analysis, which allowed evaluation of contributions in terms of per-procedure and collective doses to the population for the practice of IR, showed a significant growth rate during the study period.


Asunto(s)
Angiografía/estadística & datos numéricos , Carga Corporal (Radioterapia) , Dosis de Radiación , Radiografía Intervencional/estadística & datos numéricos , Radiometría/estadística & datos numéricos , Procedimientos Quirúrgicos Vasculares/estadística & datos numéricos , Humanos , Italia/epidemiología , Estudios Longitudinales
3.
J Clin Ultrasound ; 40(3): 167-73, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22359401

RESUMEN

Periodic quality control (QC) for ultrasound scanners checks their overall performance, reducing the risk of inaccurate diagnoses. Data from routine annual QC activity were analyzed to optimize the scheduling and the criteria of further QC programs. Among all the ultrasound scanners (68 transducers) in use at the Regional Medical Department of the Aosta Valley, which are currently tested, 48.6% showed problems, mainly (35.3%) related to defects detectable by physical and mechanical inspection. Nearly two-thirds of these problems impacted QC parameters. Failures were significantly related to the workload and to the "technological level" of the equipment. QC scheduling should therefore include a daily/weekly physical inspection in addition to a more complete, objective and software algorithms-based test, the frequency of which should be tailored on the basis of the equipment characteristics. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012.


Asunto(s)
Ultrasonografía/instrumentación , Ultrasonografía/normas , Diseño de Equipo , Control de Calidad , Ultrasonografía Doppler/instrumentación , Ultrasonografía Doppler/normas
4.
Sensors (Basel) ; 8(6): 3656-3664, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27879899

RESUMEN

A wavelet multi-component decomposition algorithm has been used for data analysis of micro-Raman spectra of blood serum samples from patients affected by pemphigus vulgaris at different stages. Pemphigus is a chronic, autoimmune, blistering disease of the skin and mucous membranes with a potentially fatal outcome. Spectra were measured by means of a Raman confocal microspectrometer apparatus using the 632.8 nm line of a He-Ne laser source. A discrete wavelet transform decomposition method has been applied to the recorded Raman spectra in order to overcome problems related to low-level signals and the presence of noise and background components due to light scattering and fluorescence. This numerical data treatment can automatically extract quantitative information from the Raman spectra and makes more reliable the data comparison. Even if an exhaustive investigation has not been done in this work, the feasibility of the follow-up monitoring of pemphigus vulgaris pathology has been clearly proved with useful implications for the clinical applications.

5.
Sensors (Basel) ; 7(10): 2049-2061, 2007 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-28903213

RESUMEN

Liquid samples of clarified apple and apricot juices at different productionstages were investigated using visible light micro-Raman spectroscopy in order to assessits potential in monitoring fruit juice production. As is well-known, pectin plays a strategicrole in the production of clarified juice and the possibility of using Raman for its detectionduring production was therefore evaluated. The data analysis has enabled the clearidentification of pectin. In particular, Raman spectra of apple juice samples from washedand crushed fruits revealed a peak at 845 cm-1 (typical of pectin) which disappears in theRaman spectra of depectinised samples. The fructose content was also revealed by thepresence of four peaks at 823 cm-1, 872 cm-1, 918 cm-1 and 975 cm-1. In the case of apricotjuice, several Raman fingerprints of ß-carotene at 1008, 1159 and 1520 cm-1 were alsohighlighted. Present results resulted interesting for the exclusive use of optical methods forthe quantitative determination of the above-mentioned substances in place of thebiochemical assays generally used for this purpose, which are time consuming and requiredifferent chemical reagents for each of them.

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