WE-E-213CD-04: CT to Cone-Beam CT Deformable Registration With Simultaneous Intensity Correction

Area of Science:

• Medical Imaging
• Image Registration
• Computational Anatomy

Background:

• Cone-beam CT (CBCT) is widely used in radiotherapy for image guidance.
• CBCT images often suffer from artifacts and intensity variations compared to planning CT scans.
• Accurate deformable image registration is crucial for effective image-guided radiotherapy.

Purpose of the Study:

• To develop and validate a robust algorithm for CT to CBCT deformable image registration.
• To address challenges posed by CBCT artifacts and intensity inconsistencies.
• To achieve accurate registration results for improved clinical applications.

Main Methods:

• Proposed a novel algorithm: Deformation with Intensity Simultaneously Corrected (DISC).
• DISC integrates an intensity correction step within the demons registration framework.
• Intensity correction matches image intensity moments within local patches between CT and CBCT.
• Algorithm implemented on GPUs using CUDA for efficient computation.

Main Results:

• DISC effectively registers CT and CBCT images, even in artifact-laden regions.
• The original demons algorithm showed tissue distortion in artifact-affected areas.
• The intensity-corrected CBCT images generated by DISC were artifact-free with similar histogram distributions to the deformed CT.

Conclusions:

• Developed a robust CT to CBCT deformable image registration method.
• The DISC algorithm successfully handles CBCT artifacts and intensity inconsistencies.
• This method yields accurate registration results, enhancing its potential for clinical use.