Summary
2019 Joint International Symposium on Electromagnetic Compatibility and Asia-Pacific International Symposium on Electromagnetic Compatibility, Sapporo
2019
Session Number:WedPM2Po
Session:
Number:WedPM2Po.20
Influence of Small Gaps in AC Magnetic Field Shielding for Image Quality of MRI Devices
Rafael Navet de Souza, Sergio Santos Muhlen,
pp.-
Publication Date:2016/10/5
Online ISSN:2188-5079
DOI:10.34385/proc.58.WedPM2Po.20
Summary:
Magnetic Resonance Imaging (MRI) is a technique that produces high-resolution volumetric images of the body without using ionizing radiations. The quality of images is greatly disturbed by environmental magnetic fields, especially of 50/60 Hz, and particularly on MRI equipment with permanent magnets, which results in the need of shielding the room where the equipment is installed. This study was carried out to quantify the influence of small gaps on the shielding junctions in the image quality of MRI equipment with permanent magnets. We present the influence of gaps in the shielding effectiveness (SE) for alternating current (AC) magnetic fields in MRI exam rooms for both ferromagnetic (NGO Fe-Si alloy) and conductive (Al) shielding and compare them. We have created a computational model of the shielding and compared the simulations results with experimental measurements using a metallic box with dimension of 1m? and gaps of 0.5 mm in the sheets junctions. The aluminum shield has proved to be advantageous for AC magnetic field shielding but suffers greater influence in the SE when the gaps are taken to account.