DETROIT (WWJ/AP) – Michigan regulators could reopen an investigation of how the Detroit Medical Center ensures that surgical instruments are clean and sterile after another dirty tool was found.

Officials with the Department of Licensing and Regulatory Affairs concluded a three-month investigation in December and notified the DMC it was no longer in violation of eight health codes.

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The next day, on Dec. 23, a laparoscopic grasper caked with old blood and brown ooze was marked as sterile and delivered to a Children’s Hospital of Michigan operating room, according to The Detroit News. The instrument was noticed and replaced before it could be used.

[Detroit Medical Center Stung By Problems With Unclean Tools: ‘It’s A Surgeon’s Nightmare’]

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The medical center says it’s “reviewing the circumstances.”

DMC has admitted that unclean surgical tools had sometimes forced doctors to delay procedures. The problems were reported in August by the newspaper.

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