Radiographic apparatus and method for monitoring the path of a thrust needle

A method for establishing a line segment as a guideline superposed on sectional images of slice planes displayed on a screen of a display monitor of a computer for running a thrust needle into a patient, the method comprising the steps of:

• displaying on the screen of the display monitor a first selected slice plane desirable for an actual needle entry point on a body surface of the patient;
• inputting a representative needle entry point at a selected location on an outer periphery of the first selected slice plane, the representative needle entry point corresponding with and being representative of the actual needle entry point;
• displaying on the screen of the display monitor a second selected slice plane desirable for an actual target point inside the patient, the second selected slice plane being different from the first selected slice plane;
• inputting a representative target point at a selected target point location inside the second selected slice plane, the representative target point corresponding with and being representative of the actual target point;
• establishing first coordinates of the representative needle entry point and second coordinates of the representative target point;
• computing the line segment based upon the first and second coordinates;
• and
• setting the line segment to be displayed as a guideline projected and superposed on said sectional images of the slice planes.