Radiation Therapy

General Overview:

Our goal is to predict treatment outcome for radiation therapy using image features from dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). We are using image data collected from 23 patients with cervical cancer who underwent radiation therapy.

2 DCE-MRI imaging studies performed for each patient, the first prior to treatment and the second 2-3 weeks into treatment. Each study consisted of a pre-contrast series and a post-contrast series.

Figure 1 : Pre-contrast

Figure 2 : Post-contrast

Image Analysis

(Left) Initial alignment of Anatomical scan (grayscale image) and DCE scan (green outline) and (Right) registered alignment

Results

Best performing classifier used pre-therapy and early therapy mean voxel intensities, both before contrast injection, with early therapy intensity distribution skewness, after contrast injection. The prediction accuracy using the support vector machine (SVM) and linear discriminant analysis (LDA) classifiers were 73.9%±13.6% and 68.5%±18.3%, respectively.

Treatment outcomes (Local Control (LC) or Local Recurrence (LR)) plotted after PCA projection of feature set

Plot showing linear classifier separation of treatment outcome classes using support vectors (encircled). Notice improperly classified points in blue near top of plot