Nearly 1,000 devices are included in a recall of GE Healthcare’s Millennium Nuclear Medical Systems after the top detector of one system detached and fell onto the detector below.

FDA said no patient injuries have been reported although there is a risk of potential life-threatening bodily harm if the detector were to detach and fall during a patient exam. The agency has identified this as a Class I recall, the most serious type of recall.

GE’s Millennium MG, Millennium MC, and Millennium Myosight Nuclear Medicine Systems manufactured between January 1997 and July 2012, and distributed between January 1997 and September 2018, are included in the recall. A total of 996 machines are being recalled. These systems are used to take images of a patient’s organs or tissue to help diagnose or treat a health condition or disease. They are designed to allow the user to acquire data for high-resolution, 3D images.

GE said it has determined that the incident that triggered the recall was caused by an improperly functioning primary motion stopper and a missing mechanical stopper, which would limit the detector’s travel beyond its limits during normal operation.

The company sent customers a letter in September instructing them to stop using the imaging systems until GE can complete a full inspection of all systems. On Nov. 6, the company reported it had completed inspections on all systems and confirmed that no related issues were found.