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H3, h6: siemens has initiated a detailed investigation of the event.The investigation is ongoing.A supplemental report will be submitted upon receipt of additional reportable information (i.E., patient injury extent, patient health status, etc.) or upon completion of the investigation.
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H3, h6: siemens healthineers (siemens) completed the investigation of the reported event.It was communicated that a patient noticed a skin rash and blister on their examined knee about 16-25 hours after their examination.The exact location of the injury on the knee is unclear.There was no serious injury associated with this issue.Siemens experts analyzed the images generated during the patient¿s examination.The complete examination of the patient¿s knee lasted 11.5 min with an active scanning time of 9.4 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 60601-2-33), i.E.The maximum applied sar was 10.5 % 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 1.98 wmin/kg which is clearly below the limit of 240 wmin/kg defined in the mr safety standard (iec 60601-2-33).Qa checks were performed and showed no signal of a technical malfunction of the system except for the bc tuning and gradient sensitivity checks.Generally, gradient sensitivity does not impact the rf field and is therefore unlikely to be related with the complaint incident.In addition, the measurement was performed using the txrx_knee coil so that the deviations of the bc tuning had no impact on the applied rf field during the examination and are therefore also unlikely to be the root cause for the heating.(overall, deviations of the bc tuning were only moderate and are unlikely to create local rf hotspots.) no anomalies are visible in the mr images of the examination from a technical point of view.The sar values were below the limit of 2 w/kg in normal operating mode during the whole examination.Based on the provided information, no clear root cause could be determined.Overall, it is unusual that no heating was experienced during or directly after the examination and the skin rash appeared approximately one day after the examination.A potential root cause might be contact with an electrically conductive object.According to the questionnaire, the patient was wearing own clothing made of ¿velvet fabric¿.Velvet typically contains different types of fibers, and it is unclear which were contained in the clothing the patient was wearing.In general, clothes, including sports clothing ¿ may contain metallic fibers that can heat up during mri examinations.The returned tx/rx knee 18 coil (material # 11292811; serial # (b)(6)) was analyzed and defective pogo pins were found.The po-go pin is a connector that connects the receiving antenna and the transmitting antenna of the upper and lower halves.If the po-go pin is damaged, the transmitting layer will require a higher power, and the transmitting power will be very high.This might cause the coil to heat up.This problem has already been known and improved pogo pin connectors have already been introduced.Unfortunately, the root cause could not be determined with certainty.This complaint has been closed.
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