Magnetic resonance imaging and thermal injury.
We read with interest the recent case report by Tanaka and coauthors (Tanaka R, Yumoto T, Shiba N, et al: Overheated and melted intracranial pressure transducer as cause of thermal brain injury during magnetic resonance imaging. Case report. J Neurosurg, published online 12 October 2012). In the report, they describe a case in which a patient sustained a thermal brain injury due to overheating of an intraparenchymal intracranial pressure (ICP) transducer (Codman MicroSensor; Johnson & Johnson, Codman & Shurtleff, Inc.) during magnetic resonance imaging (MRI) within a 1.5 T Magnetom Vision, Siemens AG. Analysis of the cause of the incident revealed that the manufacturer’s MRI safety recommendations had not been followed. Specifically, the transducer had been positioned in a straight line during imaging instead of in the coiled configuration advised by the manufacturer. This resulted in heating of the wire within the transducer due to resonant radiofrequency (RF) waves produced by the “antenna effect”.
Medical Research Council (G0600986)
Medical Research Council (G9439390)