ESTRO 2024 - Abstract Book

S2979

Interdiscplinary - Other

ESTRO 2024

Operational Ontology for Radiation Oncology. Int J Radiat Oncol Biol Phys. 2023 May 25;S0360-3016(23)00525–4. PMID: 37244628

3. Potters L, Gaspar LE, Kavanagh B, Galvin JM, Hartford AC, Hevezi JM, Kupelian PA, Mohiden N, Samuels MA, Timmerman R, Tripuraneni P, Vlachaki MT, Xing L, Rosenthal SA, American Society for Therapeutic Radiology and Oncology, American College of Radiology. American Society for Therapeutic Radiology and Oncology (ASTRO) and American College of Radiology (ACR) practice guidelines for image-guided radiation therapy (IGRT). Int J Radiat Oncol Biol Phys. 2010 Feb 1;76(2):319–325. PMID: 20117284 4. Hayman JA, Dekker A, Feng M, Keole SR, McNutt TR, Machtay M, Martin NE, Mayo CS, Pawlicki T, Smith BD, Kudner R, Dawes S, Yu JB. Minimum Data Elements for Radiation Oncology: An American Society for Radiation Oncology Consensus Paper. Pract Radiat Oncol. 2019 Nov;9(6):395–401. PMID: 31445187

2914

Poster Discussion

Dosimetric dental mapping in post-radiotherapy dental care for children.

Luc Ollivier 1 , Gregory Delpon 1 , Anne- Gaelle Chaux 2 , Tony Prud homme 2 , Mélanie Dore 1 , Stephane Supiot 1

1 Institut de Cancérologie de l'ouest, Radiotherapy, Nantes, France. 2 CHU Nantes, Odontology, Nantes, France

Purpose/Objective:

The purpose of this study was to create dental radiation maps for children and to measure the dose delivered to each dental environment (teeth, periodontium and bone), and to assess its accuracy and relevance for guiding dental care in the context of intensity-modulated radiotherapy (IMRT).

Material/Methods:

Radiation plans were extracted then a visual estimation of the dose received by each teeth was performed blind of any delineation. Second the manual segmentation considered as a reference was performed by 2 dental surgeons and 2 radiation oncologists on 6 patients distributed according to dental development: two aged between 0-3 years, two between 3-6 years, one between 6-12 years, one more than 12 years. Lastly a semi automatic algorithm yDERO automated creation of cylindrical regions of interest (ROI) including teeth, bone and periodontium and was used for permanent teeth. Four arches corresponding to 8-tooth sectors were then semi automatically generated. Thirty-two cylindrical ROI corresponding to each tooth and surrounding periodontium were created by linear interpolation. Minimum doses (Dmin), average doses (Davg), maximum doses (Dmax) of the ROI were extracted and included in a database and labeled based on the universal numbering system.

Results:

Dmin, Davg, Dmax calculated using manual contours were considered as reference and compared with the doses estimated visually or using the semi-automatic algorithm yDERO. Doses estimation compared to the reference dose were more accurate with yDERO respect to visual estimation for Davg (Δ0,09 Gy) and Dmax (Δ 0,76 Gy) but