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Dosimetric comparison between manual and inverse optimization in brachytherapy planning for cervical cancer |
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| รหัสดีโอไอ | |
| Creator | 1. Pornsuree Chaiyarith 2. Ekkasit Tharavichitkul 3. Somsak Wanwilairat |
| Title | Dosimetric comparison between manual and inverse optimization in brachytherapy planning for cervical cancer |
| Publisher | Faculty of Associated Medical Sciences, Chiang Mai University |
| Publication Year | 2560 |
| Journal Title | Journal of Associated Medical Sciences |
| Journal Vol. | 50 |
| Journal No. | 2 |
| Page no. | 293-299 |
| Keyword | Manual optimization, inverse optimization, CT-based brachytherapy |
| ISSN | 25396056 |
| Abstract | Background: For image-guided brachytherapy (IGBT) for cervical cancer, manual optimization is normally used in routine practice. However, to define the dwell position and dwell time, experiences of the planner is the key factor. The inverse optimization which dwell weight and dwell time were calculated by computer was introduced to improve planning quality. However, evaluation of the benefit of inverse optimization in comparison to manual optimization is controversial.Purpose: To compare dosimetric parameters between manual and inverse optimize planning for cervical cancer treated by IGBT.Materials and methods: Forty-four CT-images set with inserted applicator of 11 cervical cancer patients were used. All patients were treated by teletherapy 50 Gy in 25 fractions and intracavitary brachytherapy with the 4 fractions of 7 Gy to D90 of HR-CTV. Manual and inverse algorithm IPSA method were used for optimization in all CT images set. Dose parameters to HR-CTV and organs at risk and optimization time consuming from both plans were compared and paired t-test was used to evaluate the difference.Results: Inverse optimization plan significantly showed higher D90 of HR-CTV than manual method. For Organs at risk, inverse optimization showed higher dose of D2cc to bladder and rectum, but lower dose to sigmoid and bowel in comparison to manual method Moreover, the optimization time was lower for inverse planning.Conclusions: The inverse optimize planning showed better target coverage dose and lower dose to bowels and sigmoid in the intracavitary planning. The inverse optimization time is significantly faster than manual optimization. |
