Abstract：
:The purpose of this study was to quantify the intrafraction motion of pediatric patients with brain tumors during radiation therapy and investigate any correlation between motion, use of general anesthesia, and daily treatment duration. 100 pediatric patients with a mean age of 8.5 years (range: 1.0 to 17.8) were included in this prospective study. Forty-one patients required general anesthesia during treatment, mean age 4.8 years; 59 patients did not, mean age 11.2 years. Each patient had an intracranial tumor and was treated in the supine position with a thermoplastic facemask and headrest for immobilization. A pretreatment localization CBCT was acquired for each treatment fraction and a post-treatment CBCT was acquired every other fraction. If the magnitude of the patient's position pre-CBCT offset was ≥ 2 mm, the position was corrected. The difference between the patient's position based on the post-CBCT and the assumed position at the start of treatment (either the pre-CBCT offset if the magnitude was < 2 mm, or 0 offset due to correction) was determined and labeled intrafraction motion. Correlations between daily treatment duration and intrafraction motion were examined. There was an average of 14.2 post-CBCTs acquired per patient. The magnitude of the mean intrafraction motion was 1.2 ± 0.8 mm for patients requiring general anesthesia, and 1.5 ± 1.2 mm for those without (p < 0.001). The mean offset in each direction was less than 0.5 mm for both cohorts. There was no correlation between daily treatment duration and the magnitude of intrafraction motion. The intrafraction motion of pediatric patients undergoing external beam therapy for intracranial tumors is small, < 2 mm, and is independent of the daily treatment duration.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Beltran C,Merchant TEdoi
10.1120/jacmp.v12i4.3609subject
Has Abstractpub_date
2011-11-15 00:00:00pages
3609issue
4issn
1526-9914journal_volume
12pub_type
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更新日期：2014-01-06 00:00:00
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更新日期：2002-04-01 00:00:00
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更新日期：2017-01-01 00:00:00
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更新日期：2015-09-08 00:00:00
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更新日期：2011-05-20 00:00:00
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