Real-time 3D-surface-guided head refixation useful for fractionated stereotactic radiotherapy

Area of Science:

• Medical Physics
• Radiotherapy Technology
• Image-Guided Therapy

Background:

• Fractionated stereotactic radiotherapy requires precise patient positioning.
• Traditional methods can be time-consuming and prone to inaccuracies.
• Real-time imaging is crucial for adaptive radiotherapy.

Purpose of the Study:

• To develop and validate a surface-guided system for accurate head refixation in radiotherapy.
• To improve the efficiency and precision of patient setup procedures.
• To minimize setup time and enhance treatment accuracy.

Main Methods:

• Utilizing real-time 3D surface imaging with a 3D video camera.
• Aligning real-time surface images with pre-treatment reference surface images (3D optical or CT/MRI-derived).
• Employing a modified iterative-closest-point algorithm for automatic surface registration and a facial monitoring technique to mitigate artifacts.

Main Results:

• Achieved patient setup times of less than 2 minutes.
• Demonstrated high accuracy and precision with isocenter shifts <1 mm and rotational errors <1 degree.
• Successfully removed image artifacts while preserving surface details for reliable head position representation.

Conclusions:

• The developed surface-guided refixation system enables accurate and precise patient positioning for fractionated stereotactic radiotherapy.
• This method significantly reduces setup time and enhances treatment delivery accuracy.
• Real-time 3D surface imaging offers a robust solution for image-guided radiotherapy head positioning.