Dataset Information

Spinal cord tolerance to single-session uniform irradiation in pigs: implications for a dose-volume effect.

ABSTRACT:

Background and purpose

This study was performed to test the hypothesis that spinal cord radiosensitivity is significantly modified by uniform versus laterally non-uniform dose distributions.

Materials and methods

A uniform dose distribution was delivered to a 4.5-7.0 cm length of cervical spinal cord in 22 mature Yucatan minipigs for comparison with a companion study in which a laterally non-uniform dose was given [1]. Pigs were allocated into four dose groups with mean maximum spinal cord doses of 17.5 ± 0.1 Gy (n=7), 19.5 ± 0.2 Gy (n=6), 22.0 ± 0.1 Gy (n=5), and 24.1 ± 0.2 Gy (n=4). The study endpoint was motor neurologic deficit determined by a change in gait within one year. Spinal cord sections were stained with a Luxol fast blue/periodic acid Schiff combination.

Results

Dose-response curves for uniform versus non-uniform spinal cord irradiation were nearly identical with ED(50)'s (95% confidence interval) of 20.2 Gy (19.1-25.8) and 20.0 Gy (18.3-21.7), respectively. No neurologic change was observed for either dose distribution when the maximum spinal cord dose was ? 17.8 Gy while all animals experienced deficits at doses ? 21.8 Gy.

Conclusion

No dose-volume effect was observed in pigs for the dose distributions studied and the endpoint of motor neurologic deficit; however, partial spinal cord irradiation resulted in less debilitating neurologic morbidity and histopathology.

SUBMITTER: Medin PM

PROVIDER: S-EPMC3526692 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Publications

Spinal cord tolerance to single-session uniform irradiation in pigs: implications for a dose-volume effect.

Medin Paul M PM Foster Ryan D RD van der Kogel Albert J AJ Sayre James W JW McBride William H WH Solberg Timothy D TD

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 20120914 1

<h4>Background and purpose</h4>This study was performed to test the hypothesis that spinal cord radiosensitivity is significantly modified by uniform versus laterally non-uniform dose distributions.<h4>Materials and methods</h4>A uniform dose distribution was delivered to a 4.5-7.0 cm length of cervical spinal cord in 22 mature Yucatan minipigs for comparison with a companion study in which a laterally non-uniform dose was given [1]. Pigs were allocated into four dose groups with mean maximum sp ...[more]

PMID: 22985780

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Dataset Information

Spinal cord tolerance to single-session uniform irradiation in pigs: implications for a dose-volume effect.

Background and purpose

Materials and methods

Results

Conclusion

Publications

Spinal cord tolerance to single-session uniform irradiation in pigs: implications for a dose-volume effect.

Similar Datasets

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