This poster is published under an
open license. Please read the
disclaimer for further details.
Keywords:
MR physics, MR, Safety, Audit and standards, Quality assurance
Authors:
A. Nitrosi, R. Sghedoni, M. Bertolini, A. Corazza, P. Pattacini, G. Tondelli, V. Ginocchi, L. Ghiddi, M. Iori; Reggio Emilia/IT
DOI:
10.1594/ecr2015/C-1155
Methods and materials
Reggio Emilia Diagnostic Imaging Department (REDID) adopts a RIS-PACS integrated dose monitoring system software called “Gray detector”.
It allows to query a huge amount of data from headers of images stored in PACS,
including MR ones (Figure 1).
For radiological exposures (e.g.
CT) reference diagnostic levels (RDL) are defined to optimize patients’ exposures.
In last years documented MRI patient adverse events are mainly related to thermal injuries due to improper patient management (eg.
patient weight uncorrectly inserted in MRI unit) or equipment use.
The SAR describes the potential for heating of the patient's tissue due to the RF energy necessary to produce the MR images.
The SAR is defined as the RF power absorbed per unit of mass of an object and is measured in watts per kilogram (W/kg).
MR limits on Specific Absorption Rate (SAR) are defined,
but a detailed monitoring of these values is unusual.
The EN/IEC 60601-2-33 1st level limit requires that the SAR value averaged on 6 minutes must be lower than 4 W/kg.
As starting point 1556 breast and 39347 brain MRI exams performed from 2011 on three 1.5T scanners by GE,
Philips and Siemens were collected.