DICOM RTSTRUCT Margin Expansion Tool (Python) – Automated OAR/PRV Generation

🚀 Expand RTSTRUCT Structures Automatically — No TPS Needed

This Python-based tool allows you to expand any ROI directly from a DICOM RTSTRUCT file with precise, isotropic margins in millimeters.

Designed for medical physicists, dosimetrists, and researchers, this script enables automated structure manipulation outside the treatment planning system (TPS) — giving you flexibility, speed, and control.

🔧 What This Tool Does

With just a few inputs, you can:

• Load a DICOM RTSTRUCT file
• Select any ROI (structure)
• Apply a user-defined margin (in mm)
• Generate a new expanded structure
• Export a modified RTSTRUCT file

⚙️ How It Works (Under the Hood)

• Converts RTSTRUCT contours → 3D binary mask
• Applies Euclidean distance transform for true isotropic expansion
• Avoids pixel-based inaccuracies
• Converts expanded mask → planar contours
• Writes back to a new RTSTRUCT file

💡 Why This Is Powerful

This tool unlocks workflows beyond TPS limitations:

• ✅ Automated PRV generation
• ✅ Batch structure processing
• ✅ Independent QA workflows
• ✅ DICOM-based research pipelines
• ✅ System-agnostic automation

👨‍⚕️ Who This Is For

• Medical Physicists
• Dosimetrists
• Radiation Oncology Researchers
• Developers working with DICOM RTSTRUCT

🛠️💡 Need customization? Contact me to adapt this tool to your workflow.