APPLICATION OF ANODA HEEL EFFECT (AHE) WITH STEPWEDGE ON THE SIGNAL TO NOISE RATIO (SNR) EFFECT AND DOSE ON COMPUTED RADIOGRAPHY (CR) IMAGES

Radiology examination is one of the supporting examinations in the field of health in enforcing the diagnosis of a disease. Radiographic examination technique is a method used to produce a radiograph with good quality so that very influential in determining the accuracy diagnosis of a disease. The quality of X-rays is the ability of X-rays that can be measured by the penetrating power of the object being passed before producing a radiograph. Giving an electric potential difference is very influential on the X-ray penetrability generated by the tube. An increase in the difference in electrical potential will affect the increase in X-ray intensity which shows the amount of photon energy coming out of the tube that depends on a certain area, distance and time. The intensity of X-rays emitted from the anode has different strengths. The difference in the distribution of X-ray intensity is due to the angular slope formed by the anode in the diode tube called the anode heel effect (AHE). The application of the anode heel effect is very helpful in obtaining quality images from body of parts to showing significant variations in thickness along the horizontal axis of the X-ray plane, which can produce optimal image quality that can be observed using computed radiography (CR). Signal to Noise Ratio (SNR), is a measure of the ratio between signal to noise. The higher the SNR value, the better the image quality and the more easily distinguishable noise. The measurement method is carried out with 6 times exposure, which is repeated 3 times on taking radiographs so that a total image of 6 images is obtained (without the application of the 3 anode heel effect and with 3 anode heel effect), and then the data will be measured SNR by using the RadiAnt Dicom program. Absorbent dose measurements were carried out 3 times without and with the application of the anode heel effect. Absorbent dosage measurements are done by placing a digital dosimeter of 4 dosimeters before and after passing stepwedge. The application of anode heel effect will affect the distribution of the absorbed dose in patients. The absorbed dose is defined as the amount of energy delivered by radiation or the amount of energy surrendered by the material's mass unity. Thus the study of the application of the anode heel effect with stepwedge to the effect of signal to noise ratio (SNR) and dose on computed radiography (CR) images.