Abstract
Background: A computed tomography (CT) scan is an imaging modality with many clinical applications. The CT number of different materials plays an important role in the accurate diagnosis of the disease and reduction of errors. Other factors, such as kilovoltage (kVp) and reconstruction kernels, may have an effect on CT numbers. The aim of this study was to investigate the impact of different levels of kVp and kernels on the CT number of the blood, fat, and water.
Methods: In this cross-sectional study, the CT numbers of the blood, fat, and water were investigated at 80 kVp, 110 kVp, and 130 kVp, as well as H31, H70, J30, and U90 reconstruction kernels using a 16-slice CT scanner (Siemens). The scanning of each material was repeated three times, and the mean CT number of each substance was extracted from the device software. The Kruskal-Wallis statistical test was used to compare CT numbers between different levels of kVp and reconstruction kernels.
Results: The results showed that the mean CT numbers of the blood, water, and fat were 55, -4.2, and -102 Hounsfield unit (HU). No significant difference was observed between the CT numbers of water, fat, and fresh blood at 80 kVp, 110 kVp, and 130 kVp (P>0.05). In addition, the difference in the CT number of fresh blood, water, and fat in reconstruction kernels H31, H70, J30, and U90 was not significant (P>0.05).
Conclusion: It was revealed that the CT number of water, fat, and blood does not change significantly with kernel and kVp, and this can help specialists in diagnosis.