System safety monitor for ct scanners

Abstract

A gantry (A) of a CT scanner system has an x-ray tube (10) and radiation detectors (14) which produce patient diagnostic data. An operator using a keyboard (20) or other manual controls operates the x-ray tube and other components of the gantry. The operator also causes a central processing unit (C) to process the diagnostic data with a selected algorithm to provide diagnostic information for display on a display (24). The same keyboard and displays are also utilized in routine service and repair processes. A system monitor (E) compares operating conditions sensed by sensors (50), such as operating temperatures and compares them with acceptable operating conditions. When the sensed conditions are unacceptable, a timer (60) is started and shuts down (68) gantry operation after a preselected duration. The operator can override (72) the timed shut down, but each such override is recorded (74) in permanent storage (32). The comparing means also compares software identification codes either for software selected on touch sensitive areas (76) of the display screen or from new software identifications read on a disk drive (22). If the identification of the requested or received software matches an authorized software identification, the software is utilized for diagnostic or service purposes. Other use of the software is blocked and the identification of any software sought to be entered is stored in the memory (32). To initiate a CT scan, a ready button (40) starts a timer (44) which enables a start button (42) to control the power to the CT scanner for a selected short duration, e.g. 30 seconds.