Dataset Information

Modeling the impact of out-of-phase ventilation on normal lung tissue response to radiation dose.

ABSTRACT:

Purpose

To create a dose-response model that predicts lung ventilation change following radiation therapy, and examine the effects of out-of-phase ventilation.

Methods

The dose-response model was built using 27 human subjects who underwent radiation therapy (RT) from an IRB-approved trial. For each four-dimensional computed tomography, two ventilation maps were created by calculating the N-phase local expansion ratio (LER_N ) using most or all breathing phases and the 2-phase LER (LER₂ ) using only the end inspiration and end expiration breathing phases. A polynomial regression model was created using the LER_N ventilation maps pre-RT and post-RT and dose distributions for each subject, and crossvalidated with a leave-one-out method. Further validation of the model was performed using 15 additional human subjects using common statistical operating characteristics and gamma pass rates.

Results

For voxels receiving 20 Gy or greater, there was a significant increase from 52% to 59% (P = 0.03) in the gamma pass rates of the LER_N model predicted post-RT Jacobian maps to the actual post-RT Jacobian maps, relative to the LER₂ model. Additionally, accuracy significantly increased (P = 0.03) from 68% to 75% using the LER_N model, relative to the LER₂ model.

Conclusions

The LER_N model was significantly more accurate than the LER₂ model at predicting post-RT ventilation maps. More accurate post-RT ventilation maps will aid in producing a higher quality functional avoidance treatment plan, allowing for potentially better normal tissue sparing.

SUBMITTER: Wallat EM

PROVIDER: S-EPMC9486957 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Publications

Modeling the impact of out-of-phase ventilation on normal lung tissue response to radiation dose.

Wallat Eric M EM Flakus Mattison J MJ Wuschner Antonia E AE Shao Wei W Christensen Gary E GE Reinhardt Joseph M JM Baschnagel Andrew M AM Bayouth John E JE

Medical physics 20200413 7

<h4>Purpose</h4>To create a dose-response model that predicts lung ventilation change following radiation therapy, and examine the effects of out-of-phase ventilation.<h4>Methods</h4>The dose-response model was built using 27 human subjects who underwent radiation therapy (RT) from an IRB-approved trial. For each four-dimensional computed tomography, two ventilation maps were created by calculating the N-phase local expansion ratio (LER<sub>N</sub> ) using most or all breathing phases and the 2- ...[more]

PMID: 32187683

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Dataset Information

Modeling the impact of out-of-phase ventilation on normal lung tissue response to radiation dose.

Purpose

Methods

Results

Conclusions

Publications

Modeling the impact of out-of-phase ventilation on normal lung tissue response to radiation dose.

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