Patent ID: 8351572
Filing Date: 2013-01-08
Classification: A61N

Abstract:
1. A method for determining a treatment dose delivered to a patient during radiation therapy based on integrated exit-transit images captured therefrom, comprising the steps of: a. establishing a plurality of reference exit images measured by a radiation detector array for a range of treatment field sizes and a range of water equivalent phantom thicknesses emulating a patient; b. determining for each of the phantom thicknesses a point spread kernel for converting the radiation exit-transit images to corresponding in air radiation intensity fluence maps, each in air radiation intensity fluence map being indicative of an input radiation dose to the phantom; c. combining the point spread kernels into at least one multi-dimensional kernel defined as a function of radius and thickness parameters; d. capturing with the radiation detector array a plurality of integrated exit images for a plurality of the treatment fields upon a patient during radiation therapy of the patient, each integrated exit image including a plurality of pixels defined with respect to the radiation detector array, the pixels each having an integrated pixel value associated therewith; e. defining for each pixel of each integrated exit image at least one water equivalent path representing a path traversed through the patient by a ray of radiation passing from a source to said pixel, the water equivalent path being calculated based upon image data established for the patient; and, f. deconvolving each of the exit-transit images with one said multi-dimensional kernel to generate a corresponding in air radiation intensity fluence map for determining the delivered dose to the patient.