The customer demonstrated that the anatomy was not visible through remote access.The probe tool was used to check the brightness values.Brightest areas had values around 190-200.Dicom headers displayed a window center (0028,1050) value of 2,700.Center value should be roughly between the brightest and darkest pixel values.It was determined that the modality is writing the center value differing from the brightest spot.It was determined at this time that the product functioned as intended and this issue was due to incorrect dicom data.A workaround was provided to the customer if the issue is encountered again.On 04-feb-2020, a software defect was discovered while investigating an issue regarding a research device.This led to a retrospective analysis of feedback tickets.The research device uses the same (b)(4) codec as the device described in this report.While the likelihood of potential serious health consequences is remote, the use of the defective software associated could result in misdiagnosis, potentially causing significant indirect harm necessitating medical intervention that is serious but temporary.This defect is only encountered in select scenarios, where a modality produces images that are compressed using (b)(4), and the image pixel data is less than 16-bit, and the "bitness" of the compressed data stream does not match that of the image pixel data.The outcome of the above is a loss of precision in the decompressed pixel data, which causes the symptoms that were reported by the customer.The root cause is that a software defect found in the device that is encountered when it is used with non-dicom compliant (b)(4) compressed images.The software improperly uses the dicom bit depth (i.E.The bits stored tag) to decompress the compressed pixel data stream for display, instead of the bit depth that is encoded in the compressed pixel data stream itself.In non-dicom compliant images where the dicom and compressed pixel data stream bit depths do not match, the software outputs an image with some loss of precision in the decompressed pixel data.In these scenarios, the modality producing the image is itself also not compliant to dicom (b)(4).Mdr reports: 3012075008-2020-00002, 3012075008-2020-00003 and 3012075008-2020-00004 have the same root cause.A capa has been opened and recall initiated to address the issue in affected devices.
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