skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dose-Volume Effects in Rat Thoracolumbar Spinal Cord: The Effects of Nonuniform Dose Distribution

Abstract

Purpose: To investigate dose-volume effects in rat spinal cord irradiated with nonuniform dose distributions and to assess regional differences in radiosensitivity. Methods and Materials: A total of 106 rats divided into three groups were irradiated with {sup 192}Ir {gamma}-rays at a high dose rate. The groups were irradiated with one, two, or six catheters distributed around the thoracolumbar spinal cord to create different dose distributions. After irradiation, the animals were tested for motor function for 9 months. The response was defined as motor dysfunction and WM or nerve root necrosis. Dose-response data were analyzed with a probit analysis as function of the dose level at a percentage of the volume (D{sub %}) and with different normal tissue complication probability models. Additionally, the histologic responses of the individual dose voxels were analyzed after registration with the histologic sections. Results: The probit analysis at D{sub 24} (24% of the volume) gave the best fit results. In addition, the Lyman Kutcher Burman model and the relative seriality model showed acceptable fits, with volume parameters of 0.17 and 0.53, respectively. The histology-based analysis revealed a lower radiosensitivity for the dorsal (50% isoeffective dose [ED{sub 50}] = 32.3) and lateral WM (ED{sub 50} = 33.7more » Gy) compared with the dorsal (ED{sub 50} = 25.9 Gy) and ventral nerve roots (ED{sub 50} = 24.1 Gy). Conclusions: For this nonuniform irradiation, the spinal cord did not show typical serial behavior. No migration terms were needed for an acceptable fit of the dose-response curves. A higher radiosensitivity for the lumbar nerve roots than for the thoracic WM was found.« less

Authors:
; ;  [1]
  1. Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)
Publication Date:
OSTI Identifier:
21036217
Resource Type:
Journal Article
Journal Name:
International Journal of Radiation Oncology, Biology and Physics
Additional Journal Information:
Journal Volume: 69; Journal Issue: 1; Other Information: DOI: 10.1016/j.ijrobp.2007.05.027; PII: S0360-3016(07)00940-6; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0360-3016
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; DOSE RATES; GAMMA RADIATION; HISTOLOGY; IRIDIUM 192; NECROSIS; NONUNIFORM IRRADIATION; RADIATION DOSE DISTRIBUTIONS; RADIATION DOSES; RADIOSENSITIVITY; RATS; SPINAL CORD

Citation Formats

Philippens, Marielle E.P., Pop, Lucas A.M., Visser, Andries G, and Kogel, Albert J. van der. Dose-Volume Effects in Rat Thoracolumbar Spinal Cord: The Effects of Nonuniform Dose Distribution. United States: N. p., 2007. Web. doi:10.1016/j.ijrobp.2007.05.027.
Philippens, Marielle E.P., Pop, Lucas A.M., Visser, Andries G, & Kogel, Albert J. van der. Dose-Volume Effects in Rat Thoracolumbar Spinal Cord: The Effects of Nonuniform Dose Distribution. United States. https://doi.org/10.1016/j.ijrobp.2007.05.027
Philippens, Marielle E.P., Pop, Lucas A.M., Visser, Andries G, and Kogel, Albert J. van der. 2007. "Dose-Volume Effects in Rat Thoracolumbar Spinal Cord: The Effects of Nonuniform Dose Distribution". United States. https://doi.org/10.1016/j.ijrobp.2007.05.027.
@article{osti_21036217,
title = {Dose-Volume Effects in Rat Thoracolumbar Spinal Cord: The Effects of Nonuniform Dose Distribution},
author = {Philippens, Marielle E.P. and Pop, Lucas A.M. and Visser, Andries G and Kogel, Albert J. van der},
abstractNote = {Purpose: To investigate dose-volume effects in rat spinal cord irradiated with nonuniform dose distributions and to assess regional differences in radiosensitivity. Methods and Materials: A total of 106 rats divided into three groups were irradiated with {sup 192}Ir {gamma}-rays at a high dose rate. The groups were irradiated with one, two, or six catheters distributed around the thoracolumbar spinal cord to create different dose distributions. After irradiation, the animals were tested for motor function for 9 months. The response was defined as motor dysfunction and WM or nerve root necrosis. Dose-response data were analyzed with a probit analysis as function of the dose level at a percentage of the volume (D{sub %}) and with different normal tissue complication probability models. Additionally, the histologic responses of the individual dose voxels were analyzed after registration with the histologic sections. Results: The probit analysis at D{sub 24} (24% of the volume) gave the best fit results. In addition, the Lyman Kutcher Burman model and the relative seriality model showed acceptable fits, with volume parameters of 0.17 and 0.53, respectively. The histology-based analysis revealed a lower radiosensitivity for the dorsal (50% isoeffective dose [ED{sub 50}] = 32.3) and lateral WM (ED{sub 50} = 33.7 Gy) compared with the dorsal (ED{sub 50} = 25.9 Gy) and ventral nerve roots (ED{sub 50} = 24.1 Gy). Conclusions: For this nonuniform irradiation, the spinal cord did not show typical serial behavior. No migration terms were needed for an acceptable fit of the dose-response curves. A higher radiosensitivity for the lumbar nerve roots than for the thoracic WM was found.},
doi = {10.1016/j.ijrobp.2007.05.027},
url = {https://www.osti.gov/biblio/21036217}, journal = {International Journal of Radiation Oncology, Biology and Physics},
issn = {0360-3016},
number = 1,
volume = 69,
place = {United States},
year = {Sat Sep 01 00:00:00 EDT 2007},
month = {Sat Sep 01 00:00:00 EDT 2007}
}