In:
PLOS ONE, Public Library of Science (PLoS), Vol. 18, No. 9 ( 2023-9-21), p. e0291712-
Abstract:
This study aimed to assess the performance of a tongue-positioning device in interfractional tongue position reproducibility by cone-beam computed tomography (CBCT). Fifty-two patients treated with radiation therapy (RT) while using a tongue positioning device were included in the study. All patients were treated with 28 or 30 fractions using the volumetric modulated arc therapy technique. CBCT images were acquired at the 1 st , 7 th , 11 th , 15 th , 19 th , 23 th , and 27 th fractions. Tongues on planning computed tomography (pCT) and CBCT images were contoured in the treatment planning system. Geometric differences in the tongue between pCT and CBCT were assessed by the Dice similarity coefficient (DSC) and averaged Hausdorff distance (AHD). Two-dimensional in vivo measurements using radiochromic films were performed in 13 patients once a week during sessions. The planned dose distributions were compared with the measured dose distributions using gamma analysis with criteria of 3%/3 mm. In all patients, the mean DSC at the 1 st fraction (pCT versus 1 st CBCT) was 0.80 while the mean DSC at the 27 th fraction (pCT versus 27 th CBCT) was 0.77 with statistical significance ( p -value = 0.015). There was no statistically significant difference in DSC between the 1 st fraction and any other fraction, except for the 27 th fraction. There was statistically significant difference in AHD between the 1 st fraction and the 19 th , 23 th , and 27 th fractions ( p -value 〈 0.05). In vivo measurements showed an average gamma passing rate of 90.54%. There was no significant difference between measurements at the 1 st week and those at other weeks. The tongue geometry during RT was compared between pCT and CBCT. In conclusion, the novel tongue-positioning device was found to minimize interfractional variations in position and shape of the tongue.
Type of Medium:
Online Resource
ISSN:
1932-6203
DOI:
10.1371/journal.pone.0291712
DOI:
10.1371/journal.pone.0291712.g001
DOI:
10.1371/journal.pone.0291712.g002
DOI:
10.1371/journal.pone.0291712.g003
DOI:
10.1371/journal.pone.0291712.g004
DOI:
10.1371/journal.pone.0291712.g005
DOI:
10.1371/journal.pone.0291712.g006
DOI:
10.1371/journal.pone.0291712.g007
DOI:
10.1371/journal.pone.0291712.t001
DOI:
10.1371/journal.pone.0291712.t002
DOI:
10.1371/journal.pone.0291712.t003
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2023
detail.hit.zdb_id:
2267670-3
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