BEUDAMED
    FDA Adverse Event Other Summary report: N

    OASIS

    MDR report key: 3072659 · Received April 17, 2013

    Report

    Report Number
    8030405-2013-00001
    Event Type
    Other
    Date Received
    April 17, 2013
    Date of Event
    November 29, 2011
    Report Date
    November 29, 2011
    Manufacturer
    HITACHI MEDICAL CORP.
    Product Code
    LNH
    PMA / PMN Number
    K072279
    Removal / Correction Number
    NA
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    CA, US
    Reporter Occupation
    OTHER HEALTH CARE PROFESSIONAL

    Narratives

    Additional Manufacturer Narrative · 1

    THE OASIS IS A 1.2 TESLA OPEN MAGNET. HITACHI CLINICAL SCIENCE STAFF REVIEWED THE IMAGES OF THE MISREAD CASE AND ATTRIBUTE THE BRIGHT SPOT TO A REPLICATION ARTIFACT AND INDICATE THAT THIS PHENOMENON IS NOT UNUSUAL. THERE WAS GENERAL AGREEMENT AMONG THE STAFF THAT THE RADIOLOGIST SHOULD HAVE UNDERSTOOD THAT THE BRIGHT AREA WAS AN ARTIFACT. HITACHI SERVICE REPLACED THE HEAD COIL AND VERIFIED THE IMAGING CHAIN WAS MEETING IMAGE QUALITY SPECIFICATIONS. THE DWI ARTIFACT IS INTERMITTENT AND THE ACTIONS TAKEN TO DATE HAVE NOT FULLY RESOLVED THE ISSUE. OTHER SITES HAVE REPORTED THE ARTIFACT, BUT THERE IS NO CONSISTENCY IN LEVEL OR FREQUENCY OF OCCURRENCE. TO DATE, WE HAVE NOT IDENTIFIED A SYSTEM MALFUNCTION AS THE ROOT CAUSE OF THE PROBLEM. THE DWI ARTIFACT DESCRIBED CAN BE CAUSED BY PT MOTION, INSTABILITY IN THE MAGNETIC FIELD, EDDY CURRENTS, ETC. SCAN PROTOCOL SETTINGS CAN AFFECT WHERE THE ARTIFACT APPEARS (WITHIN THE ANATOMY OR NOT). DWI ARTIFACTS ARE AN INDUSTRY-WIDE PROBLEM. HITACHI IS CONTINUING TO INVESTIGATE THIS PHENOMENON IN AN ATTEMPT TO MINIMIZE ITS IMPACT ON IMAGE QUALITY.

    Description of Event or Problem · 1

    ON (B)(6) 2011, (B)(6) HOSPITAL REPORTED THE FOLLOWING REGARDING THE HITACHI OASIS OPEN MRI SYSTEM: "WE KEEP GETTING THIS ARTIFACT ON OUR DIFFUSIONS THAT MIMIC A STROKE. IT'S PRETTY PRONOUNCED TO THE POINT THAT ONE OF OUR RADIOLOGIST MISREAD IT AS AN INFARCT ON A RECENT PT. WE HAD ANOTHER ONE TODAY; PRETTY BRIGHT. I KNEW IT WAS ARTIFACT SINCE IT'S ALWAYS IN THE SAME SPOT. WE REPEATED THE EXAM CHANGING THE FOV FROM 260 TO 300 AND IT ELIMINATES MOST OF THE ARTIFACT, BUT NOT ALL". THE REFERENCED CASE WAS A BRAIN EXAM, USING A DIFFUSION WEIGHTED IMAGING (DWI) SCAN PROTOCOL. HITACHI CONFIRMED THAT THE PT WAS NOT TREATED AND SUFFERED NO INJURY DUE TO THE FALSE POSITIVE FINDING.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    165560 OASIS MAGNETIC RESONANCE DIAGNOSTIC DEVICE LNH HITACHI MEDICAL CORP. OASIS NA

    Patients

    Seq Age Sex Outcome Treatment
    1 Other