Abstract: A radiation treatment system (100) for accurately delivering radiation to a targeted site within a cancer patient (108) that includes a modular patient support system and a patient positioner (114). The modular patient support system includes a modularly expandable patient pod (200) and at least one immobilization device, such as, for example, a rigid moldable foam cradle (350). The patient pod (200) includes a generally hemi-cylindrical support shell (212) that extends longitudinally between proximal edge (214) and distal edge (216), and transversely between two lateral edges (222, 224). In one embodiment, the lateral edges (222, 224) are tapered to minimize edge effects that result when radiation beams traverse the lateral edges (222, 224).

Abstract: A patient alignment system for a radiation therapy system. The alignment system includes multiple external measurement devices which obtain position measurements of components of the radiation therapy system which are movable and/or are subject to flex or other positional variations. The alignment system employs the external measurements to provide corrective positioning feedback to more precisely register the patient and align them with a radiation beam. The alignment system can be provided as an integral part of a radiation therapy system or can be added as an upgrade to existing radiation therapy systems.