The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 27, 2009
Filed:
Nov. 07, 2008
Sami Pekka Siljamaki, Helsinki, FI;
Katja Marika Pesola, Vantaa, FI;
Sami Pekka Siljamaki, Helsinki, FI;
Katja Marika Pesola, Vantaa, FI;
Varian Medical Systems International AG, Zug, CH;
Abstract
The present invention provides an intensity modulated radiation therapy (IMRT) method for treating a target region that minimizes the tongue and groove effect. By minimizing that effect, striping in the final delivered fluence is reduced, which improves the overall quality of the radiation delivery. In the method, compensating functions C(x) are added to leaf coordinates a(x) and b(x) for all of the leaf pairs i in a leaf sequence algorithm, where C(x) is chosen to match the mechanical limitations of the MLC and to minimize non-weighted or weighted sums of the tongue and groove effects, where the weighting is time-dependent, position-dependent, or time- and position-dependent, or to minimize the total treatment time, changes to the original MLC sequence, or the tongue and groove effect distribution variance in spatial or temporal coordinates.