کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1880156 1042896 2008 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Implementation of Fiducial-Based Image Registration in the Cyberknife Robotic System
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم تشعشع
پیش نمایش صفحه اول مقاله
Implementation of Fiducial-Based Image Registration in the Cyberknife Robotic System
چکیده انگلیسی
Fiducial-based image registration methodology as implemented in the Cyberknife system is explored. The Cyberknife is a radiosurgery system that uses image guidance technology and computer-controlled robotics to determine target positions and adjust beam directions accordingly during the dose delivery. The image guidance system consists of 2 x-ray sources mounted on the ceiling and a detection system mounted on both sides of the treatment couch. Two orthogonal live radiographs are taken prior to and during patient treatment. Fiducial markers are identified on these radiographs and compared to a library of digital reconstructed radiographs (DRRs) using the fiducial extraction software. The fiducial extraction software initially sets an intensity threshold on the live radiographs to generate white areas on black images referred to as “blobs.” Different threshold values are being used and blobs at the same location are assumed to originate from the same object. The number of blobs is then reduced by examining each blob against a predefined set of properties such as shape and exposure levels. The remaining blobs are further reduced by examining the location of the blobs in the inferior-superior patient axis. Those blobs that have the corresponding positions are assumed to originate from the same object. The remaining blobs are used to create fiducial configurations and are compared to the reference configuration from the computed tomography (CT) image dataset for treatment planning. The best-fit configuration is considered to have the appropriate fiducial markers. The patient position is determined based on these fiducial markers. During the treatment, the radiation beam is turned off when the Cyberknife changes nodes. This allows a time window to acquire live radiographs for the determination of the patient target position and to update the robotic manipulator to change beam orientations accordingly.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Medical Dosimetry - Volume 33, Issue 2, Summer 2008, Pages 156-160
نویسندگان
, , ,