Reference frame for stereotactic radiosurgery using skeletal fixation

Abstract

A body-support frame comprising a horizontal table having two adjustable ces that can be moved along the main axis of the table for straddling a patient lying within the frame. Each brace is equipped with a swiveled clamp attached to an adjustable system of bracket-arms for the skeletal fixation and immobilization of the patient craniad and caudad to the area of interest. The frame contains orthogonal scales for orthogonal localization and measurements of the area of interest with reference to a chosen set of coordinates within the table. The frame also contains three adjustable radiographic calibration targets that are used for selectively setting a plane of reference in the proximity of the area of interest, so that the plane may be used for lining up the frame with radiographic imaging and radiation treatment apparatus. An additional, adjustable radiographic target may be provided for fine calibration of the position of the reference coordinates by permitting its placement as near as possible to the area of interest externally to the body of the patient. The apparatus is used to determine the exact coordinates of the area of interest with reference to the chosen reference point while the body of the patient is immobilized. These coordinates are then translated to an exact position in the radiation therapy apparatus for subsequent stereotactic radiosurgery.