The flat-panel detector is mainly composed of a flat-shaped pixel matrix silicon layer or selenium layer electrolytic layer top electrode and a protective layer. Silicon (or selenium) has high photoconductivity and strong sensitivity to X-rays. After a certain number of exposures, it is easy to cause aging and damage. Generally <5, flat panel detectors can be patched with software; but >10 forms a white spot, which cannot be patched. And as the number of exposures increases, the number of dead pixels will gradually increase to form bad tracks. Therefore, the dead pixels should be maintained in time when they just appear. According to the requirements, the flat panel detector needs to be maintained regularly, and it is required to be calibrated strictly in accordance with the maintenance manual provided by the manufacturer. The main contents are:
① Offset correction (Office correction);
② Gain correction (Gain correction);
③ Bad point correction (Bad point correction).
Nowadays, most of the DR’s operating interfaces have a calibration program for flat panel detectors, and the factory also requires hospitals to calibrate the flat panel within a certain period of time.
Whether it is an indirect or direct flat panel detector, long-term exposure to X-rays will cause the electrolytic conversion layer to age and reduce its use efficiency. This is related to the cumulative dose. Therefore, a shutter can be used for inspection sites that require high kilovolts and high currents, such as the lumbar spine lateral position, to reduce useless X-ray radiation, thereby prolonging the service life of the detector. In addition, pay attention to the cleanliness of the flat panel detector surface, such as dirt or blood stains. Be careful to handle it with care during use, and do not drop, bump, or scratch the surface.