The customer also noted the images appear fine when viewed in the vrad web viewer.He also said that they appeared normal in an older version of cc workstation (2.0 sp1 - open-source).The synaptive rep initiated screen share to observe.Sample was a digital x-ray from a konica minolta portable scanner.W/l was changed to around 491/177 before it was viewable.Initial w/l (auto) = 4096/2047.Opened a few more images that were very similar.The customer explained that the previous version was cc ws 2.0 sp1 (open source), but was unable to confirm whether these particular images opened correctly with that version.The synaptive rep gave the customer a workaround via the window/level hotkey configuration.On 18-mar-2019 an investigation found the issue to be identical to feed-3544 (reported as 3012075008-2020-00001): the bits stored (0028,0101) value is set to 12-bit in the dicom header however, it appears the jpeg 2000 compressed pixel data is actually 16-bit.When the tag value is edited to 16, the image appears correct (i.E.Not dark) on load.Therefore, the dicom data is incongruent.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 jpeg 2000 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 jpeg 2000, 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 jpeg 2000 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 ps3.5 8.2.4.Mdr reports: 3012075008-2020-00001, 3012075008-2020-00002, and 3012075008-2020-00003 have the same root cause.A capa has been opened and recall initiated to address the issue in affected devices.
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