Share Email Print
cover

Proceedings Paper

The phase transition method for SAR measurement in MRI
Author(s): Rocco Romano; Fausto Acernese; Silvia Vilasi; Fabrizio Barone
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

During an MR procedure, the patient absorbs a portion of the transmitted RF energy, which may result in tissue heating and other adverse effects, such as alterations in visual, auditory and neural functions. The Specific Absorption Rate (SAR), in W/kg, is the RF power absorbed per unit mass of tissue and is one of the most important parameters related with thermal effects and acts as a guideline for MRI safety. Strict limits to the SAR levels are imposed by patient safety international regulations (CEI - EN 60601 - 2 - 33) and SAR measurements are required in order to verify its respect. The recommended methods for mean SAR measurement are quite problematic and often require a maintenance man intervention and long stop machine. For example, in the CEI recommended pulse energy method, the presence of a maintenance man is required in order to correctly connect the required instrumentation; furthermore, the procedure is complex and requires remarkable processing and calculus. Simpler are the calorimetric methods, also if in this case long acquisition times are required in order to have significant temperature variations and accurate heat capacity knowledge (CEI - EN 60601 - 2 - 33). The phase transition method is a new method to measure SAR in MRI which has the advantages to be very simple and to overcome all the typical calorimetric method problems. It does not require in gantry temperature measurements, any specific heat or heat capacity knowledge, but only mass and time measurement. On the other hand, it is necessary to establish if all deposited power SAR can be considered acquired and measured. In this paper, that will be shown.

Paper Details

Date Published: 9 April 2010
PDF: 9 pages
Proc. SPIE 7650, Health Monitoring of Structural and Biological Systems 2010, 76503B (9 April 2010); doi: 10.1117/12.846397
Show Author Affiliations
Rocco Romano, Univ. degli Studi di Salerno (Italy)
Istituto Nazionale di Fisica Nucleare (Italy)
Fausto Acernese, Univ. degli Studi di Salerno (Italy)
Istituto Nazionale di Fisica Nucleare (Italy)
Silvia Vilasi, Univ. degli Studi di Salerno (Italy)
Istituto Nazionale di Fisica Nucleare (Italy)
Fabrizio Barone, Univ. degli Studi di Salerno (Italy)
Istituto Nazionale di Fisica Nucleare (Italy)


Published in SPIE Proceedings Vol. 7650:
Health Monitoring of Structural and Biological Systems 2010
Tribikram Kundu, Editor(s)

© SPIE. Terms of Use
Back to Top