Patent ID: 8020227

Claim:
In equipment for treating a target within a patient using an ionizing radiation beam, an apparatus for modifying a patient support system to be compatible with a magnetic field used for localization, comprising: a support structure having a first longitudinal support member and a second longitudinal support member, the first and second longitudinal support members being rigid and comprising materials that are at least substantially dielectric, and the first and second support members being configured to be carried by the patient support system; a panel carried by and positioned at a top of the first and second longitudinal support members, the panel comprising materials that are at least substantially dielectric and having a portion that is compatible with an ionizing radiation beam; and a pass-through zone positioned on the panel between the first and second longitudinal support members, the pass-through zone including a rigid grid having a plurality of cross members, not including a high density core, and the pass-through zone being configured to provide a navigational zone wherein a signal transmitted from a marker implanted in a patient in the navigational zone is not affected by conductive components of the patient support system to an unacceptable degree.