Amit M Sawant, Age 589923 Alcosta Blvd, San Ramon, CA 94583

8331531, Dec 11, 2012

Mar 15, 2010

12/661303

Rebecca Fahrig - Palo Alto CA, US
Norbert J. Pelc - Los Altos CA, US
Kim Pauly - Stanford CA, US
Greig C. Scott - Palo Alto CA, US
Amit Sawant - Mountain View CA, US
Paul J. Keall - Palo Alto CA, US
Lei Xing - Palo Alto CA, US
Steven M. Conolly - Palo Alto CA, US

The Board of Trustees of the Leland Stanford Junior University - Palo Alto CA
The Regents of the University of California - Berkeley CA

A61N 5/10
G01N 23/04

378 65, 378 63

The present invention provides a radiotherapy treatment apparatus that includes a treatment beam, a magnetic field disposed parallel collinear to the treatment beam, and a target that is disposed along the treatment beam. The treatment beam can be a charged particle beam, a proton beam, an electron beam, or a linear accelerator (Linac) beam. The magnetic field is from a magnetic resonance imager (MRI), a megavolt x-ray imager, or a kilovolt x-ray imager and is disposed to operate in coordination with operation of the treatment beam and to narrow the beam. The tumor is disposed to rotate with respect to the treatment beam and the magnetic field, or the treatment beam and the magnetic field are disposed to rotate up to 360 with respect to the target when mounted to a ring gantry. The apparatus can include a rotation angle dependent shim disposed to account for Earth's magnetic field.

2008015, Jul 3, 2008

Dec 11, 2007

12/001762

Paul J. Keall - Stanford CA, US
Amit Sawant - Los Altos CA, US
Yelin Suh - Stanford CA, US
Sergey Povzner - Burlingame CA, US
Herbert Cattell - Mountain View CA, US

A61N 5/10

378 65

A method of continuous real-time monitoring and positioning of multi-leaf collimators during on and off radiation exposure conditions of radiation therapy to account for target motion relative to a radiation beam is provided. A prediction algorithm estimates future positions of a target relative to the radiation source. Target geometry and orientation are determined relative to the radiation source. Target, treatment plan, and leaf width data, and temporal interpolations of radiation doses are sent to the controller. Coordinates having an origin at an isocenter of the isocentric plane establish initial aperture end positions of the leaves that is provided to the controller, where motors to position the MLC midpoint aperture ends according to the position and target information. Each aperture end intersects a single point of a convolution of the target and the isocenter of the isocentric plane. Radiation source hold-conditions are provided according to predetermined undesirable operational and/or treatment states.

2008028, Nov 13, 2008

May 12, 2008

12/119464

Paul J. Keall - Stanford CA, US
Amit Sawant - Los Altos CA, US
Peter Maxim - Palo Alto CA, US
Yelin Suh - Palo Alto CA, US
Lei Xing - Palo Alto CA, US
Byung Chul Cho - Palo Alto CA, US

A61B 6/00

600426, 378 20

A method and system are disclosed for estimating internal position information of a target in real-time based on a single gantry-mounted x-ray imager and a respiratory signal. The x-ray imaging is done periodically to limit radiation dosage. Initial parameters for the estimation model are determined in a pre-treatment session using four dimensional computed tomography (4D CT) in combination with a respiratory signal acquired from the patient. The model parameters are updated during treatment based on the periodic x-ray image data and the respiratory signal.