1、Set of Disconnected Data间断的数据设置Series of contiguous 2-D axial images of specified thickness are required.一系列特殊厚度的2维轴图像Conventional CT 传统传统CTSingle-Slice Spiral CT 单层螺旋单层螺旋CT Continuous Volume of Data数据连续Spiral pattern of volumetric data acquired 旋转模式获得数据“Step and Shoot”Gantry Rotation间断照射扫描架旋转间断照射扫描
2、架旋转Gantry containing x-ray tube and detectors returned to starting position after one 360-degree rotation,patient advanced fixed distance through gantry.扫描架包括X-rays电子管和检测器,旋转360度后,再回到正常位置,因为病人先前被固定在扫描架上。.Continuous Gantry Rotation连续扫描架旋转连续扫描架旋转Gantry housing x-ray tube and detectors rotates uninterr
3、upted around the patient while patient continuously advanced through gantry 当病人连续的通过扫描架时,有X-ray电子管和检测器的扫描架绕病人持续旋转。Single-Slice Spiral CT单层螺旋CTMultislice Spiral CT多层螺旋CT One Detector Row一个检测面Radiation penetrating through patient is registered by one row of detectors 穿过病人的射线是被一排检测器记录。Four Detector Row
4、s四个检测面Radiation penetrating through patient is registered by four rows of detectors 穿过病人的射线被四排检测器记录。One Slice一层Spiral path traced around patient yields one slice per gantry rotation 扫描架每旋转一圈,产生一层断面图像Four Slices四层Spiral path traced around patient yields four slices per gantry rotation 扫描架每旋转一圈,可产生四层断
5、面图像Slice width断层厚度断层厚度Tissue voxel组织容量成分组织容量成分Image pixel成相像素成相像素Matrix短短阵阵Gray scale灰尺灰尺Air 1000空气空气-1000Soft tissue structures are usually displayed within this range.软组织通常呈现在这软组织通常呈现在这个区域个区域+150-1500 Bone+1000骨骨+1000White白色白色Black黑色黑色window Width窗口宽度窗口宽度window Level窗口水窗口水平面平面Soft tissue window:WW 400;WL 60Bone window:WW 3500;WL 500Data from NRPB 19921cran.caud.RUHContrast enhancement 对比增强Exact location精确定位Size+extend尺寸+扩大Number of fragments碎片数量Soft tissue swelling 软组织肿胀Bilateral fracture M1Food sinus maxillarisZrich University