Siemens has completed an investigation of the reported event.Assessment of the log files does not indicate a system failure or malfunction and no non-conformity was identified.The complete fmri examination of the volunteer patient lasted 87,8 min with an active scanning time of 75,1 min.No abnormality was found which would indicate a system malfunction.The complete measurement was performed in the normal operating mode.The sar values were within the limits defined by the mr safety standard (iec (b)(4)), i.E.The maximum applied sar was 23% of the normal mode limit.The applied rf in this case should not represent a risk under normal circumstances and scan conditions.Furthermore, the patient absorbed 7,0 wmin/kg which is clearly below the limit of 240 wmin/kg defined in the mr safety standard (iec (b)(4)).The ecg peru has been replaced and evaluated and no issues were found.The peru showed no problems during test.There was a visible deformation of the battery, however testing was okay.The battery was replaced, and the deformed battery was sent to the supplier for further analysis.The supplier checked the charging and discharging characteristics of the battery as well as the capacity.All measurements showed no damage of the battery.The only damage was the visible deformation which according to the supplier was not the result of an overstressing of the battery.Furthermore, the integrated safety circuit functioned without any issue (overvoltage and overtemperature).The passed test inhouse also confirmed that safety circuits integrated in the pcba were not damaged.It is suspected that the heat development was due to the high operation time, but still in defined range.It is assumed that the required cushion was not used appropriately, and this led to the patient complaint.An analysis of battery issues in relation to overstressed batteries was done.There were no indications that show battery specific problems.In summary no hardware or software problem was found which would explain the reported burn of the patient.The manufacturer is not considering further actions resulting from this event as no systematic error has been recognized.
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