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IMPROVEMENT OF DOSE CALCULATION ACCURACY ON kV CBCT IMAGES WITH CORRECTED ELECTRON DENSITY TO CT NUMBER CURVE
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 Title & Authors
IMPROVEMENT OF DOSE CALCULATION ACCURACY ON kV CBCT IMAGES WITH CORRECTED ELECTRON DENSITY TO CT NUMBER CURVE
Ahn, Beom Seok; Wu, Hong-Gyun; Yoo, Sook Hyun; Park, Jong Min;
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 Abstract
To improve accuracy of dose calculation on kilovoltage cone beam computed tomography (kV CBCT) images, a custom-made phantom was fabricated to acquire an accurate CT number to electron density curve by full scatter of cone beam x-ray. To evaluate the dosimetric accuracy, 9 volumetric modulated arc therapy (VMAT) plans for head and neck (HN) cancer and 9 VMAT plans for lung cancer were generated with an anthropomorphic phantom. Both CT and CBCT images of the anthropomorphic phantom were acquired and dose-volumetric parameters on the CT images with CT density curve (CTCT), CBCT images with CT density curve () and CBCT images with CBCT density curve () were calculated for each VMAT plan. The differences between vs. were similar to those between vs. for HN VMAT plans. However, the differences between vs. were larger than those between vs. for lung VMAT plans. Especially, the differences in and of lung target volume were statistically significant (4.7% vs. 0.8% with p = 0.033 for and 4.8% vs. 0.5% with p = 0.030 for ). In order to calculate dose distributions accurately on the CBCT images, CBCT density curve generated with full scatter condition should be used especially for dose calculations in the region of large inhomogeneity.
 Keywords
Cone beam computed tomography;Dose calculation;Inhomogeneity correction;Volumetric modulated arc therapy;
 Language
English
 Cited by
1.
Assessment of intraoperative 3D imaging alternatives for IOERT dose estimation, Zeitschrift für Medizinische Physik, 2017, 27, 3, 218  crossref(new windwow)
 References
1.
Maund IF, Benson RJ, Fairfoul J, Cook J, Huddart R, Poynter A. Image Guided Radiotherapy of the Prostate using Daily Cone Beam CT - The Feasibility and Likely Benefit of Implementing a Margin Reduction. Brit J Radiol. 2014;87:20140459. crossref(new window)

2.
Ding GX, Duggan DM, Coffey CW. Characteristics of kilovoltage x-ray beams used for cone-beam computed tomography in radiation therapy. Phys Med Biol. 2007; 52(6):1595- 615. crossref(new window)

3.
Yan D, Ziaja E, Jaffray D, Wong J, Brabbins D, Vicini F, Martinez A. The use of adaptive radiation therapy to reduce setup error: a prospective clinical study. Int J Radiat Oncol. 1998;41(3):715-20. crossref(new window)

4.
Veiga C, McClelland J, Moinuddin S, Lourenco A, Ricketts K, Annkah J, Modat M, Ourselin S, D'Souza D, Royle G. Toward adaptive radiotherapy for head and neck patients: Feasibility study on using CT-to-CBCT deformable registration for "dose of the day" calculations. Med Phys. 2014;41(3):031703. crossref(new window)

5.
Guan H, Dong H. Dose calculation accuracy using cone-beam CT (CBCT) for pelvic adaptive radiotherapy. Phys Med Biol. 2009;54(20):6239-50. crossref(new window)

6.
Rong Y, Smilowitz J, Tewatia D, Tome WA, Paliwal B. Dose calculation on kV cone beam CT images: an investigation of the Hu-density conversion stability and dose accuracy using the site-specific calibration. Med Dosim. 2010;35(3): 195-207. crossref(new window)

7.
Yang Y, Schreibmann E, Li T, Wang C and Xing L, Evaluation of on-board kV cone beam CT (CBCT)-based dose calculation. Phys Med Biol, 2007. 52(3): p. 685-705. crossref(new window)

8.
Qian J, Lee L, Liu W, Chu K, Mok E, Luxton G, Le QT, Xing L. Dose reconstruction for volumetric modulated arc therapy (VMAT) using cone-beam CT and dynamic log files. Phys Med Biol. 2010;55(13):3597-610. crossref(new window)

9.
Reggiori G, Mancosu P, Tozzi A, Cantone MC, Castiglioni S, Lattuada P, Lobefalo F, Cozzi L, Fogliata A, Navarria P, Scorsetti M. Cone beam CT pre- and post-daily treatment for assessing geometrical and dosimetric intrafraction variability during radiotherapy of prostate cancer. J Appl Clin Med Phys. 2011;12(1):141-152.

10.
Jin X, Hu W, Shang H, Han C, Yi J, Zhou Y, Xie C. CBCT-based volumetric and dosimetric variation evaluation of volumetric modulated arc radiotherapy in the treatment of nasopharyngeal cancer patients. Radiat Oncol. 2013;8:279. crossref(new window)