The clinical value of volume calculating program utilizing 3-D CT for neurosurgery

X-ray CT is widely used for the evaluation of the treatment of tumors by surgery, radiotherapy or chemotherapy. However, most of evaluations have been carried out employing two dimensional projections. These methods don't provide a truly objective evaluation, because the tissue and the lesions has not two dimensional, but three-dimensional extension threfore. three-dimensional evaluation should be employed. We have investigated volume calculation of the region of interest (ROI). The input profile of this slice is displayed by window processing and sequence of points. The number of voxels in the region is calculated, and calculation of voxels for all of slices including interpolated slices is repeated. The volume of the ROI is obtained by multipling the total number of voxels by the precalculated volume of a voxel. Several cases of metastatic brain tumor, malignant lymphoma and malignant glioma were presented. Especially in the case of malignant lymphoma, tumor volumes before and after radiotherapy were correctly estimated and marked reduction of the tumor volume by radiotherapy was demonstrated. It is concluded that in future a reduction in the processing time and automatic extraction of ROI will be feasible. (author)