This work describes the characterization of various Fricke-Agarose-Xylenol gels (FXG) dosimeters using NMR relaxometry and MRI analysis. Using X-rays from a clinical linear accelerator (LINAC), the gels were irradiated in the dose range from 0 Gy to 20 Gy. The photon sensitivity of the FXGs was measured in terms of NMR relaxation rates; its dependence on radiation dose was determined as a function of ferrous ammonium sulfate contents (from 0.5 mM to 5 mM). Furthermore, the stability of the NMR signal was monitored over several days after irradiation. These measurements were aided by Magnetic Resonance Imaging (MRI) scans which allowed three-dimensional (3D) dose mapping. In order to maximize the MRI response, a systematic study was performed to optimize acquisition sequences and parameters. In particular, we analyzed the dependence of MRI signal on the repetition time (TR) and on the inversion time (TI) using inversion recovery sequences. The results are reported and discussed from the point of view of the dosimeter use in clinical radiotherapy. This work highlights that the optimization of additive content inside gel matrix is fundamental for optimizing photon sensitivity of these detectors.

Marrale, M., Brai, M., Gagliardo, C., Gallo, S., Longo, A., Tranchina, L., et al. (2014). Correlation between ferrous ammonium sulfate concentration, sensitivity and stability of Fricke gel dosimeters exposed to clinical X-ray beams. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION B, BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 335 [10.1016/j.nimb.2014.05.012].

Correlation between ferrous ammonium sulfate concentration, sensitivity and stability of Fricke gel dosimeters exposed to clinical X-ray beams

MARRALE, Maurizio;BRAI, Maria;GAGLIARDO, Cesare;GALLO, Salvatore;LONGO, Anna;TRANCHINA, Luigi;COLLURA, Giorgio;LO CASTO, Antonio;MIDIRI, Massimo;
2014

Abstract

This work describes the characterization of various Fricke-Agarose-Xylenol gels (FXG) dosimeters using NMR relaxometry and MRI analysis. Using X-rays from a clinical linear accelerator (LINAC), the gels were irradiated in the dose range from 0 Gy to 20 Gy. The photon sensitivity of the FXGs was measured in terms of NMR relaxation rates; its dependence on radiation dose was determined as a function of ferrous ammonium sulfate contents (from 0.5 mM to 5 mM). Furthermore, the stability of the NMR signal was monitored over several days after irradiation. These measurements were aided by Magnetic Resonance Imaging (MRI) scans which allowed three-dimensional (3D) dose mapping. In order to maximize the MRI response, a systematic study was performed to optimize acquisition sequences and parameters. In particular, we analyzed the dependence of MRI signal on the repetition time (TR) and on the inversion time (TI) using inversion recovery sequences. The results are reported and discussed from the point of view of the dosimeter use in clinical radiotherapy. This work highlights that the optimization of additive content inside gel matrix is fundamental for optimizing photon sensitivity of these detectors.
Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Settore FIS/01 - Fisica Sperimentale
Settore MED/36 - Diagnostica Per Immagini E Radioterapia
Settore ING-IND/20 - Misure E Strumentazione Nucleari
http://www.sciencedirect.com/science/article/pii/S0168583X14005497
Marrale, M., Brai, M., Gagliardo, C., Gallo, S., Longo, A., Tranchina, L., et al. (2014). Correlation between ferrous ammonium sulfate concentration, sensitivity and stability of Fricke gel dosimeters exposed to clinical X-ray beams. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION B, BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 335 [10.1016/j.nimb.2014.05.012].
File in questo prodotto:
File Dimensione Formato  
ISI_GEL_1.pdf

Solo gestori archvio

Descrizione: Articolo
Dimensione 806.93 kB
Formato Adobe PDF
806.93 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/10447/96300
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 31
  • ???jsp.display-item.citation.isi??? 31
social impact