Relationship of image quality and exposure dose on bovines femur bone using fluoroscopy at Hospital Serdang

Fluoroscopy is a modality that utilizes the energy of radiation specifically X-ray for the purpose of diagnostic. This results in exposure dose to patients and operating personnel. In order to reduce the radiation risk to patient and operating personnel the exposure dose should be optimized. The main objective of this research is to study the relationship between the image quality and the exposure dose given by a fluoroscopy machine on a bovine's femur bone. The image quality was determined under the aspect of spatial resolution and image contrast. Wires of different quantity and resolution values of 0.5 lp/ mm, 1.5 lp/ mm, 2.5 lp/ mm, 3.5 lp/ mm and 4.5 lp/ mm were used to determine the image quality produced. The kVp and mAs were adjusted until a good quality image is formed and the exposure dose produced is recorded. The results show that the image quality increases linearly to the exposure dose produced but when the extreme values are used the image quality becomes poor. The kVp and mAs values that produced the best quality image is 70 kVp and 1 mAs with an optimum exposure dose of 1.34 μSv/ h. This value is much lower compared to the exposure dose produced by automatic mode which is commonly used in the daily procedure of the fluoroscopy with a value of 1.68 μSv/ h. Thus instead of using the automatic mode, these kVp and mAs values could be implemented in femur diagnostic using fluoroscopy so that high quality image is produced with optimize exposure dose. (author)