Superimposed needle targeting is a method of orienting a needle or slender instrument to a desired target specified in a fluoroscopic view. This mimics the way that physicians commonly proceed with manual access under fluoroscopy guidance:

• The skin entry point is chosen so that in fluoroscopy it appears superimposed over the target.
• The needle is placed with the tip at the skin entry point and oriented so that in fluoroscopy it appears as a point superimposed over the target. This insures that the target is on the path of the needle.
• If a mechanical system is used, this direction is locked by the arm.

a) Photo of clinical intervention
b) Needle superimposed over target in AP view, c) Lateral view showing needle at calix target

For needle insertion, the C-Arm (fluoroscopy head) is then rotated to a lateral view in order to gain needle depth perception. The needle is inserted (manually or under joystick control) under direct fluoroscopic observation. The method was implemented on the PAKY, RCM, and AcuBot X-Ray guided systems.