TAILIEUCHUNG - Báo cáo khoa học: "Statistical analysis of IMRT dosimetry quality assurance measurements for local delivery guideline"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Radiation Oncology cung cấp cho các bạn kiến thức về ngành y đề tài: Statistical analysis of IMRT dosimetry quality assurance measurements for local delivery guideline. | Chung et al. Radiation Oncology 2011 6 27 http content 6 1 27 RADIATION ONCOLOGY RESEARCH Open Access Statistical analysis of IMRT dosimetry quality assurance measurements for local delivery guideline Jin Beom Chung1 Jae Sung Kim1 Sung Whan Ha2 and Sung-Joon Ye2 3 Abstract Purpose To establish our institutional guideline for IMRT delivery we statistically evaluated the results of dosimetry quality assurance DQA measurements and derived local confidence limits using the concept confidence limit of mean . Materials and methods From June 2006 to March 2009 206 patients with head and neck cancer prostate cancer liver cancer or brain tumor were treated using LINAC-based IMRT technique. In order to determine site specific DQA tolerances at a later stage a hybrid plan with the same fluence maps as in the treatment plan was generated on CT images of a cylindrical phantom of acryl. Points of measurement using a cm3 ion-chamber were typically located in the region of high and uniform doses. The planar dose distributions perpendicular to the central axis were measured by using a diode array in solid water with all fields delivered and assessed using gamma criteria of 3 3 mm. The mean values and standard deviations were used to develop the local confidence and tolerance limits. The dose differences and gamma pass rates for the different treatment sites were also evaluated in terms of total monitor uints MU MU cGy and the number of PTV s pieces. Results The mean values and standard deviations of ion-chamber dosimetry differences between calculated and measured doses were for H N cancer for prostate and abdominal cancer and for brain tumor. Most of measured doses agreed with the calculated doses within a tolerance limit of 3 recommended in the literature. However we found some systematic under-dosage for all treatment sites. The percentage of points passing the gamma criteria averaged over all treatment sites was

TÀI LIỆU LIÊN QUAN
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.