Paper
9 March 2014 The phase transition method for SAR measurement in MRI
R. Romano, R. Canonico, F. Acernese, G. Giordano, F. Barone
Author Affiliations +
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. Nevertheless, in order to consider this method it is necessary to verify that all deposited SAR power can be considered acquired and measured. In this paper considerations about this aspect are conducted.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
R. Romano, R. Canonico, F. Acernese, G. Giordano, and F. Barone "The phase transition method for SAR measurement in MRI", Proc. SPIE 9064, Health Monitoring of Structural and Biological Systems 2014, 90642M (9 March 2014); https://doi.org/10.1117/12.2044066
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Synthetic aperture radar

Tellurium

Tissues

Magnetic resonance imaging

Time metrology

Cesium

Scanners

RELATED CONTENT


Back to Top