Patent ID: 8576980

Claim:
A computer implemented method of interrogating volumetric data, the method comprising the steps of: defining a reference surface relative to the volumetric data; providing an interrogation window lying in a movable interrogation plane intersecting the reference surface and the interrogation window intersecting the volumetric data, wherein translation and/or rotation of the interrogation plane provides a corresponding movement of the interrogation window; said interrogation plane being associated with a pole, which lies in the interrogation plane, about which pole said interrogation plane is rotatable, and for each movement of the interrogation plane, determining the point of intersection of said pole and said reference surface, determining the relative angle of rotation of said interrogation plane about said pole and determining the angle of inclination of said pole to said reference surface; and on the basis of said determinations, providing a sectional image through the volumetric data corresponding to the position of the interrogation window within the volumetric data, wherein said interrogation plane has two or three degrees of rotational freedom and two degrees of translational freedom such that said interrogation plane is only translatable across said reference surface.