Learning objectives
MR safety and compatibility are internationally recognized as important issues for medical devices.
Testing of devices is important as well as the MR labelingto provide important informationfor the MRuser interface at the MR console for scanning of implant patients safely.
The reader shall be enabled to differentiate between different MR interactionsexistent formedical devices in the MR environment.
Understanding the technical complexity of MR test results is the basisforinterpreting these fromMR labelingand apply the parameter atthe MR system.
Please note that an "MR conditional" device labeling...
Background
MR scanning of electrically conductive implants is contraindicated without using device labels ''MR safe'' or ''MR conditional''.Devices that can be exposed to an MR environment must be tested for magnetically induced forces,
torques,
RF- and gradient induced interactions,
malfunction as well as MR image artifacts.
Standardized test methods are established.
Further standard development is work in progress e.g.
RF and gradient induced voltages,
vibration,
heating as well asfunctional electromagnetic interferenceissues.
Test results must be intelligibly transferred into a comprehensiveimplant labeling considering readability and adaptability for...
Imaging findings OR Procedure details
Chapter 1: MR interactions
The following interactions of a medical device can be identified for the MR environment:
Magnetically induced displacement force (static,
dynamic)
Magnetically induced torque (static,
dynamic)
Radio frequency (RF) inducedheating and
Gradient induced heating
RF and Gradient induced voltages (stimulation,
activation)
Gradient induced vibration
Malfunction of the device within the MR environment (dependent on individual demands)
Malfunctionof the MR system = image quality issues(SNR,
B0-homogeneity,
etc.)
Artifacts
Chapter 2: MR standard test procedures
Today'sMR implant labelingis based onstandardized testing of above mentioned...
Conclusion
Standardized MR labeling ofdevicesis compulsory for providing comprehensive and reliable information for the daily MR-clinical routine.
Standardized information
minimize patient risk
guide development of MR-suitable devices
support MR users.
In addition,
the comprehesive MR safety education of the MR user is very important for interpreting MR labeling data correctly and individual enough for the specific case.
Personal Information
Gregor SCHAEFERS obtained his Dipl.-Ing.
(FH)degree in medical engineering from the University of Applied Sciences Fachhochschule Gelsenkirchen,
Germanyin 2001.
He is founder,
shareholderand managing directorof MR:comp GmbH (www.mrcomp.com),
a specialized testinginstitution for MR safety and compatibility testing of medical devices.
He is memberofDIN,
ISO andIEC as well asASTMstandardization committees and workingin the field of MR safety and compatibilityfor developmentand optimization ofMR testing methods since 1998.
MR:comp GmbH
Testing Services for MR Safety & Compatibility
Buschgrundstr.
33
45894 Gelsenkirchen
Germany
fon: +49 (0)209 1497730-0
fax: +49...
References
ASTM F2052-06e1,
“Standard Test Method for Measurement of Magnetically Induced Displacement Force on Medical Devices in the Magnetic Resonance Environment”; 2006,
www.astm.org
ASTM F2213-06,
“Standard Test Method for Measurement of Magnetically Induced Torque on Passive Implants in the Magnetic Resonance Environment”; 2006,
www.astm.org
ASTM F2182-02a,
“Standard Test Method for Measurement of Radio Frequency Induced Heating Near Passive Implants During Magnetic Resonance Imaging”; 2002,
www.astm.org
ASTM F2119-01,
“Standard Test Method for Evaluation of MR Image Artifacts from Passive Implants”; 2001,
www.astm.org
ASTM F2503-08,
“Standard Practice for...