The invivo engineering team investigated the field findings and found that ktrans is rendered the wrong color, leading to visually underestimating areas of large ktrans.The defect also impacts two other pharmacokinetic maps kep and iaugc.Investigation identified an additional defect with a similar root cause.The apparent diffusion coefficient map (adc) can be displayed as either a greyscale image or a color overlay.In both cases, if the adc is computed on-the-fly by dynacad, the adc values and colors are incorrect on a remote client.This defect does not impact the adc maps computed externally (e.G the adc maps computed from the mr system).The adc values are scaled by a factor that can be either greater than or lower than one.Per health hazard evaluation hhe mr-1085-2018, pk analysis is a weak indicator of suspicion of disease.The hhe team estimates that by itself this defect could result in rarely occurring harms; however, due to the co-occurrence of the other defect found during investigation the hhe team estimates and concurs that there is a reasonable probability of harm due to the co-occurrence of the defect.The decision that there is an unacceptable risk was signed off on 24-jan-2018.The root cause is attributed to design.The solution involves a correction of the scaling factor that is exchanged between the client and server for some pk overlays and on-the-fly calculations.This calculation is correct when computed on the server but the client-server synchronization implementation needs to be changed to ensure the correct value is received by the client.A mandatory field action has been reported to the fda on 24-jan-2018.(b)(4).
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