Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application?
Purpose: To report our experience of dosimetric comparison of IPSA and manual plans, with a focus on the use ofhelp structures (HS) during optimization. Material and methods: 33 patients who underwent MR image-based HDR intracavitary-brachytherapy for cervixcancer based on GYN-ESTRO recommendations...
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| Format: | Article |
| Language: | English |
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Termedia Publishing House
2011-09-01
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| Series: | Journal of Contemporary Brachytherapy |
| Subjects: | |
| Online Access: | http://www.termedia.pl/Physics-Contributions-Does-help-structures-play-a-role-in-reducing-the-variation-of-dwell-time-in-IPSA-planning-for-gynaecological-brachytherapy-application-,54,17414,1,1.html |
| _version_ | 1819070777993986048 |
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| author | Swamidas Jamema Umesh Mahantshetty DD Deshpande Smriti Sharma SK Shrivastava |
| author_facet | Swamidas Jamema Umesh Mahantshetty DD Deshpande Smriti Sharma SK Shrivastava |
| author_sort | Swamidas Jamema |
| collection | DOAJ |
| description | Purpose: To report our experience of dosimetric comparison of IPSA and manual plans, with a focus on the use ofhelp structures (HS) during optimization. Material and methods: 33 patients who underwent MR image-based HDR intracavitary-brachytherapy for cervixcancer based on GYN-ESTRO recommendations were selected for evaluation. Tandem/ovoid (T/O) and Vienna applicatorswere used. HS of diameter of 5 mm were drawn around the tandem/needles/ovoid and ring. Three plans weregenerated: manual optimized plan (MOPT), IPSA without help structures (IPSA_woHS) and IPSA with help structures(IPSA_wHS). Dose-volume parameters and the loading pattern were evaluated. Results: For T/O, the use of HS did not make significant impact in the dose-volume parameters and in the loadingof tandem and ovoids, however steep variation was found in the individual dwell time. In case of Vienna applicator,inclusion of HS in the optimization made a significant impact in loading of needles. The percentage ratio oftotal time of needles to the tandem (TN/T%) was found to be 14 ± 2.5, 53 ± 9, 22 ± 6 for MOPT, IPSA_woHS andIPSA_wHS, respectively, which implies that in IPSA_woHS the dwell time in needles were half of the dwell time inthe tandem, while in MOPT the needles were loaded only in 14%, and in IPSA_wHS it was 22% of the dwell timeof tandem. Inclusion of HS in the optimization has reduced the contribution of dwell time of needle in IPSA_wHS.The individual variation of dwell time was also reduced in IPSA_wHS, however drawing of HS is a time consumingprocedure and may not be practical for a routine practice. Conclusion: The role of HS was evaluated for IPSA for T/O and Vienna-applicator, the use of HS may be beneficialin case of combined intracavitary – interstitial approach. |
| first_indexed | 2024-12-21T17:11:20Z |
| format | Article |
| id | doaj.art-9cdb6f42a6d44ea39100990756c04cc7 |
| institution | Directory Open Access Journal |
| issn | 1689-832X 2081-2841 |
| language | English |
| last_indexed | 2024-12-21T17:11:20Z |
| publishDate | 2011-09-01 |
| publisher | Termedia Publishing House |
| record_format | Article |
| series | Journal of Contemporary Brachytherapy |
| spelling | doaj.art-9cdb6f42a6d44ea39100990756c04cc72022-12-21T18:56:24ZengTermedia Publishing HouseJournal of Contemporary Brachytherapy1689-832X2081-28412011-09-0133142149Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application?Swamidas JamemaUmesh MahantshettyDD DeshpandeSmriti SharmaSK ShrivastavaPurpose: To report our experience of dosimetric comparison of IPSA and manual plans, with a focus on the use ofhelp structures (HS) during optimization. Material and methods: 33 patients who underwent MR image-based HDR intracavitary-brachytherapy for cervixcancer based on GYN-ESTRO recommendations were selected for evaluation. Tandem/ovoid (T/O) and Vienna applicatorswere used. HS of diameter of 5 mm were drawn around the tandem/needles/ovoid and ring. Three plans weregenerated: manual optimized plan (MOPT), IPSA without help structures (IPSA_woHS) and IPSA with help structures(IPSA_wHS). Dose-volume parameters and the loading pattern were evaluated. Results: For T/O, the use of HS did not make significant impact in the dose-volume parameters and in the loadingof tandem and ovoids, however steep variation was found in the individual dwell time. In case of Vienna applicator,inclusion of HS in the optimization made a significant impact in loading of needles. The percentage ratio oftotal time of needles to the tandem (TN/T%) was found to be 14 ± 2.5, 53 ± 9, 22 ± 6 for MOPT, IPSA_woHS andIPSA_wHS, respectively, which implies that in IPSA_woHS the dwell time in needles were half of the dwell time inthe tandem, while in MOPT the needles were loaded only in 14%, and in IPSA_wHS it was 22% of the dwell timeof tandem. Inclusion of HS in the optimization has reduced the contribution of dwell time of needle in IPSA_wHS.The individual variation of dwell time was also reduced in IPSA_wHS, however drawing of HS is a time consumingprocedure and may not be practical for a routine practice. Conclusion: The role of HS was evaluated for IPSA for T/O and Vienna-applicator, the use of HS may be beneficialin case of combined intracavitary – interstitial approach.http://www.termedia.pl/Physics-Contributions-Does-help-structures-play-a-role-in-reducing-the-variation-of-dwell-time-in-IPSA-planning-for-gynaecological-brachytherapy-application-,54,17414,1,1.htmlimage based brachytherapyinverse planningIPSA |
| spellingShingle | Swamidas Jamema Umesh Mahantshetty DD Deshpande Smriti Sharma SK Shrivastava Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? Journal of Contemporary Brachytherapy image based brachytherapy inverse planning IPSA |
| title | Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? |
| title_full | Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? |
| title_fullStr | Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? |
| title_full_unstemmed | Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? |
| title_short | Does help structures play a role in reducing the variation of dwell time in IPSA planning for gynaecological brachytherapy application? |
| title_sort | does help structures play a role in reducing the variation of dwell time in ipsa planning for gynaecological brachytherapy application |
| topic | image based brachytherapy inverse planning IPSA |
| url | http://www.termedia.pl/Physics-Contributions-Does-help-structures-play-a-role-in-reducing-the-variation-of-dwell-time-in-IPSA-planning-for-gynaecological-brachytherapy-application-,54,17414,1,1.html |
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