Optimized target localization in stereotactic radiosurgery using real-time digital portal images

Area of Science:

• Medical Physics
• Radiotherapy
• Image-guided therapy

Background:

• Accurate target localization is crucial in stereotactic radiosurgery (SRS) to maximize radiation dose to the tumor while minimizing damage to surrounding healthy tissues.
• Current methods may face challenges with precision due to digitized errors and input data inaccuracies.
• Real-time feedback during treatment is essential for adaptive radiosurgery.

Purpose of the Study:

• To develop and validate an optimized method for real-time target localization in SRS.
• To address the non-linear multi-variable optimization problem in target reconstruction.
• To establish a reliable accuracy metric for the proposed localization method.

Main Methods:

• Formulating target reconstruction as a non-linear multi-variable optimization problem.
• Solving the optimization using the Gaussian least square differential correction (GLSDC) method.
• Defining an indirect reference factor (shortest distance between two X-rays to the target) to assess accuracy.

Main Results:

• The GLSDC method effectively reconstructs the target position.
• Experimental results demonstrate the method's accuracy with a reference factor below 1.0 mm for correct data.
• The proposed algorithm supports on-line target localization directly on the digital portal imaging device.

Conclusions:

• The developed method provides an accurate and efficient approach for on-line target localization in SRS.
• The GLSDC method and the reference factor offer a robust solution for optimizing SRS procedures.
• This technique enhances the precision and safety of image-guided radiosurgery.