Python Script: Detect Small Treatment Apertures from DICOM RTPLAN

DICOM RTPLAN Small Field Detector (Python)

Build practical DICOM engineering skills with this educational Python script.

This tool analyzes a DICOM RTPLAN file and automatically detects control points that contain very small treatment apertures.

Instead of relying on a treatment planning system, all calculations are derived directly from DICOM metadata.

The script reconstructs aperture geometry using MLC positions, leaf boundaries, and jaw positions.

It then generates warnings whenever a control point falls below a user-defined threshold.

What the script calculates

For every beam and every control point:

✅ Average MLC opening

✅ Aperture span using active leaf widths

✅ Jaw span (if available)

✅ Automatic warning generation for small apertures