Siemens completed the investigation of the reported event.It was reported that the patient underwent an mri shoulder examination on (b)(6) 2022 using the magnetom altea system.The patient has tinnitus, which became allegedly more insistent due to the mr examination.It was reported the patient was wearing headphones during examination, and no other hearing protection was provided.The customer protocols of the patient's examination were tested inhouse on a similar magnetom altea system with identical software.The acoustical noise was measured with a brüel & kjaer lan-xi system (type 3050-b-040, serial number (b)(6)) at the area of possible head position of the patient.All measured acoustic noise values were clear below 99db(a) - the patient limit according to nema ms 4-2010 standard.The customer did not use loud protocols during the patient's examination.The customer's mr system has been checked and found to be in specification.Therefore, it is comparable with the siemens test system.Furthermore, no similar incidents have been reported to siemens from the customer.Generally, the maximum acoustic noise at magnetom altea systems measured according to the nema standard is 113.8 db(a) and 118.8 db peak.That measurement procedure includes the search for the loudest spot.Therefore, hearing protection with a noise attenuation of at least 19 db needs to be applied to the patient.As stated in the magnetom family operator manual - mr system and coils, syngo mr xa31 print no.Mr-02601g.621.07.02.02 (page 33) and the magnetom altea system owner manual print no.Mr-04009g.623.37.02.02 (page 10) patients shall be provided with appropriate hearing protection that lowers noise to at least 99 db(a).Both provide clear instructions and warnings regarding noise levels and the respective hearing protection required.As stated in the user manual, the headphones provided by siemens mr are not classified as hearing protection.They are suitable for the patient communication but do not have a specified noise attenuation value.Ear plugs with a noise attenuation coefficient equal or greater than the required hearing protection are considered suitable hearing protection.Assessment of the reported incident does not indicate a system failure or malfunction and no non-conformity was identified.However, the fact that a patient with tinnitus problems underwent mr scans without suitable hearing protection and even if the protocols were not too loud compared to the patient limit of 99db(a) they are still loud especially for noise sensitive persons.The root cause is that the patient did not wear appropriate hearing protection.
|