ESTRO 2024 - Abstract Book

S3867

Physics - Image acquisition and processing

ESTRO 2024

The proposed method required no manual input and could thus be applied to the test data set easily. Figure 2(a) shows for each region of interest the proportion of voxel with significant change to the first fraction for each patient and each fraction. For patients 1, 4 and 5, the proportion of changing voxels was low throughout the treatment. For patients 2 and 3, a large number of voxels showed a change between the simulation and the first fraction. For patient 2, further changes occurred early during treatment while the images of patient 3 were more stable, except for an outlier at fraction 10 likely caused by inconsistent image quality. Patient 6 only started showing large intensity changes late during treatment.

Figure 2(b) shows a slice of the first fraction image of each patient with the significant intensity changes to the last fraction shown as a colored overlay. For patients 1, 4 and 5, the changes are mostly limited to deformations in resection cavities and CSF structures. For patients 2 and 6, large changes occur inside the GTV, but for the former the intensity increases while for the latter it decreases.

Conclusion: