Investigation of Meningioma Physical Coefficients Pre- and Post-Contrast Using CT Technology

One of the most significant physical processes used in medicine is the computed tomography (CT) scan, which relies on the interaction of electromagnetic radiation energy (X-rays) with human tissue. In this research, a head CT protocol was used to image a patient (female, 40 years old) in two stages: before and after contrast agent injection. The mean values ​​of Hounsfield unit (HU) for the images were extracted and analyzed by comparing the physical principles Linear Attenuation coefficient (LAC) and Half Value Layer (HVL) for both stages. Where a relatively small increase in the value of LAC was observed in the specific area of ​​the left hemisphere of the brain compared to the corresponding area of ​​the right hemisphere. This finding is matched by a decrease in the value of HVL for the same areas, and this means a relatively small increase in the density of the specific area of ​​the left hemisphere, which indicates the discovery of an abnormal mass, but it does not appear prominently due to the iso-density. In post-injection stage, it was found that the difference between the values ​​of LAC and HVL for both regions of each hemisphere of the brain became higher than in the first stage due to the absorption of the contrast agent by the detected mass (in the abnormal area) and showed a strong, homogeneous enhancement of it and became whiter than the rest of the surrounding normal tissue. A higher LAC value for this mass means an increase in hyper-density and thus a lower HVL value, all of which means a higher attenuation of the X-rays falling on the brain tissue. Based on the investigated coefficients, shape, and location of the mass, the case was diagnosed as a meningioma.