Tomographic image diagnostic method and apparatus including automatic ROI setting means

摘要

In a tomographic image diagnostic apparatus, a region of interest is automatically set on a tomographic image by recognizing actual positions of a phantom based upon CT (computerized tomographic) values of the phantom. The phantom is made of a base portion having a first reference CT value and a plurality of rods each having a second reference CT value. The region of interest is defined by recognizing the gravity centers of these rods. Said apparatus comprises: image memory for storing image data of an object and a phantom made of a plurality of reference substances and a base portion; a storage for previously storing a first reference CT value used for the base portion of the phantom, and also a second reference CT value used for each of the reference substances; a first detector for detecting a position of the phantom by comparing an actually measured first CT value of the base portion with the first reference CT value previously stored in the storage; a processor for performing both profile and filtering processes on the detected position of the phantom so as to obtain processed positional data of the phantom; a second detector for detecting positions of the reference substances contained in phantom by comparing an actually measured second CT value of each of the reference substances with the second reference CT value previously stored in the storage; and, a defining units for automatically defining a position of a region of interest with respect to the tomographic image data based upon the detected positions of the reference substances.