Siemens received feedback from the customer reporting that the displayed standard uptake value (suv) was incorrect during the case as it was not reconstructed from the very beginning.This occurred when the customer viewed the list mode reconstruction data with mi applications on the syngo multimodality workplace, which was installed on customer's biograph 40 unit.According to the customer, the displayed suv was wrong in the reported case as it was not being reconstructed from the very beginning.Incorrect suv may lead to a potential misdiagnosis and incorrect patient treatment.The reported issue occurred in (b)(6).
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**resubmission of initial report due to report code error** the root cause of the reported issue was identified as follows.The reported issue a known limitation of suv (standardized uptake value) calculation in mi (molecular imaging) application; suv is not accurate if a delay was performed in the beginning of reconstruction due to which series date/time and acquisition date/time differ from each other.The viewing application has to compute the suv based on the injected dose, patient weight, and tissue concentration in the area of interest.The viewing application will extract the injected dose, series time, and patient weight from the image header information to accurately calculate the suv.The challenge with the special reconstructed list mode datasets is that the user has an option to use a delay in the reconstruction of the data.If the delay option is used in the beginning of the list mode data, the series time (0008,0031) and the acquisition time (0008,0032) will differ.In this case the system cannot distinct which of the two times to use in the individual case.For this application it was defined to use the 'series time' by default.The reported behavior of the mi apps is related to a technical constraint, which is known to the users.A general caution regarding influence of several factors to accuracy of the suv is present in the operator manual.Users are trained during clinical education that suv calculations are variable due to acquisition parameters and patient condition.The suv value of the list mode is not the only input to the diagnosis.The reported issue was re-evaluated as non-reportable adverse event and it was determined that no field safety corrective action is required.
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