Purpose: The built-in collimator in medical diagnostic X-ray equipment, which can be only adjusted rectangular direction, can expose unnecessary radiation dose to not only patients but also radiographers and degrade X-ray images. So, a Multi-leaf collimator (MLC) was devised to make an optimized field of view as well as image fusion with infrared thermal imaging to improve diagnosis.

Meterials and Methods: An MLC which can adjust an optimized field of view over the human body curvature in medical diagnostic X-ray equipment was designed, and then attached under the traditional adjustable rectangular collimator(ARC) in order to analyze dose area product, scattered radiation dose, shielding rate, leakage dose, contrast resolution, signal to noise ratio, and measurement of image profile. Image fusion with X-ray image and infrared thermal imaging was implemented.

Result: The result of measurement in dose area product with the applied MLC, it was significantly reduced by 22.9%, 31.3%, and 8.6% in hand, skull, and abdomen respectively. With the MCL, scattered radiation dose in skull projection was decreased by 14.55% at 50 cm and 11.94% at 100 cm horizontally and 7.12% and 7.16% vertically. At 15/16 points on the horizon and at 8/7 points on the vertical there were considerable reduced. Scattered radiation dose in hand projection, there declined by 14.39% at 50 cm, and by 15.51% at 100 cm horizontally, and by 14.01% at 50cm and by 14.13% at 100cm vertically. The dose reduced at 15/16 points on the horizon and at 8/8 points on the vertical, and there was invalid reduction partially. By the result of comparison and analysis of shielding rate, leakage dose, SNR, and image profile, the two collimators had similar or insignificant changes was observed, and there were no significant changes statistically. Therefore, it is possible to fuse anatomical information of X-ray images and physiological information of infrared thermal imaging, and as a result, it will contribute to improve the diagnosability.

Improvements/Applications: This study was designed to evaluate the performance of multi-leaf collimator for diagnostic X-ray devices and to implement fusion images of X-ray and infrared images.