A MR-TRUS Registration Method for Ultrasound-Guided Prostate Interventions

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Urology

Background:

• Accurate registration of Magnetic Resonance Imaging (MRI) and Transrectal Ultrasound (TRUS) is crucial for effective prostate interventions.
• Internal prostate deformation during procedures can lead to registration inaccuracies.
• Existing methods may not fully account for subject-specific biomechanical properties.

Purpose of the Study:

• To develop and validate a novel MR-TRUS prostate registration method.
• To improve the accuracy of MR-targeted, US-guided prostate interventions.
• To predict and compensate for internal prostate gland deformation using a subject-specific strain model.

Main Methods:

• Combined a subject-specific prostate biomechanical model with B-spline transformation for MR-TRUS registration.
• Generated a 3D prostate strain map using ultrasound elastography.
• Constrained B-spline transformation using prostate tissue gradient maps to model deformation.

Main Results:

• Validated the method with a prostate phantom, achieving a mean Target Registration Error (TRE) of 1.3 mm.
• Successfully performed MR-TRUS registration in 5 prostate cancer patients with a mean TRE < 2 mm.
• Demonstrated accurate and robust estimation of internal prostate gland deformation.

Conclusions:

• The proposed MR-TRUS registration method accurately estimates internal prostate deformation.
• This technique holds significant value for improving prostate cancer diagnosis and treatment planning.
• The method offers a robust approach for MR-targeted, US-guided prostate interventions.