Abstract
In inverse planning of IMRT, optimum intensity maps are generated using an optimization algorithm. In this paper, impacts of two different optimization algorithms on the intensity map in IMRT treatment planning were evaluated. These were from the steepest descent (SD) and simulated annealing (SA) methods. The following five patterns were compared: [1] SD with calculation time of 5 min; [2] SD with the terminal criterion based on cost function; [3] SA with calculation time of 5 min; [4] SA with the terminal criterion; and [5] SA with the terminal criterion using a smoothing filter. Differences of D(95%) for the planning target volume, V(70Gy) for the rectum wall and the bladder wall were up to 0.5, 1.8 and 3.2 %, respectively in all patterns. The dosimetric impact was negligible. In contrast, generated intensity maps were sensitive to the algorithms. Intensity maps generated by SA tended to have much fluctuation due to numerical artifacts compared to those generated by SD. The difference in the profile was over 7 % between the algorithms. The smoothing filter decreased the fluctuation in intensity maps of SA. In conclusion, it is important to understand impacts of optimization algorithms on the intensity map and the dose distribution.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 97-107 |
| Number of pages | 11 |
| Journal | Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics |
| Volume | 26 |
| Issue number | 3 |
| State | Published - 2006 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Medicine(all)
Cite this
Impact of optimization algorithms on the intensity map in IMRT treatment planning. / Shimada, Mari; Nakamura, Mitsuhiro; Miyabe, Yuki; Yamamoto, Tokihiro; Teshima, Teruki; Narita, Yuichiro; Mizowaki, Takashi; Nagata, Yasushi; Hiraoka, Masahiro.
In: Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics, Vol. 26, No. 3, 2006, p. 97-107.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Impact of optimization algorithms on the intensity map in IMRT treatment planning
AU - Shimada, Mari
AU - Nakamura, Mitsuhiro
AU - Miyabe, Yuki
AU - Yamamoto, Tokihiro
AU - Teshima, Teruki
AU - Narita, Yuichiro
AU - Mizowaki, Takashi
AU - Nagata, Yasushi
AU - Hiraoka, Masahiro
PY - 2006
Y1 - 2006
N2 - In inverse planning of IMRT, optimum intensity maps are generated using an optimization algorithm. In this paper, impacts of two different optimization algorithms on the intensity map in IMRT treatment planning were evaluated. These were from the steepest descent (SD) and simulated annealing (SA) methods. The following five patterns were compared: [1] SD with calculation time of 5 min; [2] SD with the terminal criterion based on cost function; [3] SA with calculation time of 5 min; [4] SA with the terminal criterion; and [5] SA with the terminal criterion using a smoothing filter. Differences of D(95%) for the planning target volume, V(70Gy) for the rectum wall and the bladder wall were up to 0.5, 1.8 and 3.2 %, respectively in all patterns. The dosimetric impact was negligible. In contrast, generated intensity maps were sensitive to the algorithms. Intensity maps generated by SA tended to have much fluctuation due to numerical artifacts compared to those generated by SD. The difference in the profile was over 7 % between the algorithms. The smoothing filter decreased the fluctuation in intensity maps of SA. In conclusion, it is important to understand impacts of optimization algorithms on the intensity map and the dose distribution.
AB - In inverse planning of IMRT, optimum intensity maps are generated using an optimization algorithm. In this paper, impacts of two different optimization algorithms on the intensity map in IMRT treatment planning were evaluated. These were from the steepest descent (SD) and simulated annealing (SA) methods. The following five patterns were compared: [1] SD with calculation time of 5 min; [2] SD with the terminal criterion based on cost function; [3] SA with calculation time of 5 min; [4] SA with the terminal criterion; and [5] SA with the terminal criterion using a smoothing filter. Differences of D(95%) for the planning target volume, V(70Gy) for the rectum wall and the bladder wall were up to 0.5, 1.8 and 3.2 %, respectively in all patterns. The dosimetric impact was negligible. In contrast, generated intensity maps were sensitive to the algorithms. Intensity maps generated by SA tended to have much fluctuation due to numerical artifacts compared to those generated by SD. The difference in the profile was over 7 % between the algorithms. The smoothing filter decreased the fluctuation in intensity maps of SA. In conclusion, it is important to understand impacts of optimization algorithms on the intensity map and the dose distribution.
UR - http://www.scopus.com/inward/record.url?scp=84982293223&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84982293223&partnerID=8YFLogxK
M3 - Article
C2 - 17344641
AN - SCOPUS:84982293223
VL - 26
SP - 97
EP - 107
JO - Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics
JF - Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics
SN - 1345-5354
IS - 3
ER -