This scanning and flexing beam guide is useful in radiation oncology.
When electron beams are used to treat cancerous tumors which are not close to the surface of a body, then there is damage to cells between the surface of the body and the tumor. This long outstanding problem is solved by the discovery shown here of a beam guide which gets an electron beam into the body and scans the beam within the body.
Devices which can be inserted into a body to deliver a radiation dose have been suggested in prior art, for example in U.S. Pat. No. 5,153,900 by Nonikos, U.S. Pat. No. 5,621,780 by Smith, and U.S. Pat. No. 5,585,643 by Johnson. Though Johnson suggests that his device might be made to be flexible, the magnet configuration suggested by Johnson can not produce the flexing, nor the scanning, shown here.
One form of the beam guide comprises a scanning magnetic field within a sleeve removably inserted in a body, the scanning magnetic field being orthogonal to an entering beam axis, and the scanning magnetic field deflecting the entering beam to form an exiting beam which exits the output end along a scan axis and enters a target volume within the body.
Other forms and objects of the invention will be comprehended in the drawings and detailed description, which will make equivalent forms and objects obvious hereafter to persons skilled in the art.