# Radiomics approach for identifying radiation-induced normal tissue toxicity in the lung

## TL;DR

This study uses radiomic features from lung images to detect radiation-induced injury and assess the effectiveness of stem cell-derived treatments in mice.

## Contribution

The novel use of radiomics to evaluate radiation injury and treatment response in lung tissue is demonstrated.

## Key findings

- Radiomic models accurately distinguished irradiated from unirradiated animals with 94% accuracy.
- EV treatment effects were identified with 85% accuracy in radiomic models.
- Radiation impact and EV sparing effects were observed in locally irradiated lungs but not in unirradiated ones.

## Abstract

Radiomic features were used in efforts to characterize radiation-induced normal tissue injury as well as identify if human embryonic stem cell (hESC) derived Extracellular Vesicle (EV) treatment could resolve certain adverse complications. A cohort of mice (n=12/group) were given whole lung irradiation (3×8Gy), local irradiation to the right lung apex (3×12Gy), or no irradiation. The hESC-derived EVs were systemically administered three times via retro-orbital injection immediately after each irradiation. Cone-Beam Computed Tomography (CBCT) images were acquired at baseline and 2 weeks after the final radiation/EV treatment. Whole lung image segmentation was performed and radiomic features were extracted with wavelet filtering applied. A total of 851 features were extracted per image and recursive feature elimination was used to refine, train and validate a series of random forest classification models. Classification models trained to identify irradiated from unirradiated animals or EV treated from vehicle-injected animals achieved high prediction accuracies (94% and 85%). In addition, radiomic features from the locally irradiated dataset showed significant radiation impact and EV sparing effects that were absent in the unirradiated left lung. Our data demonstrates that radiomics has the potential to characterize radiation-induced lung injury and identify therapeutic efficacy at early timepoints.