| Abstrakt: |
Maintain image quality is to conduct quality assurance routinely on CT scan. There are several important parameters in the assessment of image quality including CT number, uniformity and linearity, low contrast. The research method uses the variation of the parameters kVp and mA with restrictions on the use of parameters only in variations of 80, 100, 140 kVp with 192 mAs and 100, 200, 300 mAs with 120 kVp. previously considered the parameters of the Phillips Ingenuity CT scan application for the head examination routine and review as a reference. The results of the study for the CT number value between the recommended HU value and the measurement of the HU value performed have a value that is close to, so that for the CT number the CT scan is still in very good range, for the Uniformity HU value at the center of the phantom -0.854±0.402 and around the phantom (clockwise 12,3,6,9) -1,374±0,396, results are uniformity still within the tolerance range of±5 HU. Linearity HU value equation linear function with R2= 0.8692, indicating that a very strong correlation between the value of the attenuation coefficient HU. Quartile analysis of HU values for the kVp and mAs varies with the results of the second quartile value. Of the variations of mAs 100, 200 and 300 there were no significant differences in the values and tended to be the same, namely for 100 mAs Q2 values=92.04, 200 mAs Q2=93.62, 300 mAs Q2 values=92.05, while in the kVp variations there were significant differences i.e. 80 kVp Q2=99.12, 140 kVp Q2=89.59. So that the HU value is not affected by the mAs parameter, it can be said that there is no significant change in image quality from the contrast resolution; low contrast but it is influenced by the kVp parameter with a value of HU increase of about 36% when kV is increased by range of 60 kVp. [ABSTRACT FROM AUTHOR] |
