[Application of multislice CT for the diagnosis of cerebro-vascular disease]

Introduction of multislice CT (MSCT) has revolutionizing the diagnosis of cerebro-vascular disease. Newly developed 32-slice MSCT enabled us to acquire isotropic volumetric data of whole brain with the resolution of 0.5-mm. CT perfusion is one of the promising application for the diagnosis of early-staged cerebral ischemia. However, it can be hazardous in terms of ionic radiation because of multiplied exposure to the same level. A new quantum denoising filter was developed in order to solve this problem. It is possible to reduce more than 80% of dose using the filter in combination with lower kv/lower mA technique. This filter can also aids to improve the detection of early CT signs, which is important for the diagnosis of cerebral ischemia. Detection of the penumbra can be made by revealing the absence of early CT sign and low perfusion area in CT perfusion. Isotropic volumetric data provided by MSCA can also be an ideal source data for the high-quality 3D-CT angiography. Improved temporal resolution of MSCT in obtaining volumetric data made it possible separated visualization of arteries and veins on single 3D-CTA image. The technique to visualize brain surface using isotropic data and volume rendering algorithm was also reported.