Monitoring prostate thermal therapy with diffusion-weighted MRI

Area of Science:

• Medical Imaging
• Oncology
• Biophysics

Background:

• Accurate tissue viability assessment is crucial for MR-guided minimally invasive therapies.
• Diffusion-weighted MRI (DWI) is explored for evaluating tissue damage during and after thermal ablation.

Purpose of the Study:

• To assess the utility of DWI and apparent diffusion coefficient (ADC) measurements for evaluating tissue damage and remodeling in canine prostates following cryoablation or high-intensity ultrasound (HIU) ablation.

Main Methods:

• Diffusion-weighted MRI (DWI) was performed on 19 canine prostates before and after cryoablation or HIU ablation.
• Apparent diffusion coefficient (ADC) values were measured in treated tissues to assess changes indicative of thermal injury and subsequent tissue recovery.

Main Results:

• A significant decrease in ADC values was observed in acute lesions (1.05±0.25x10⁻³ mm²/s) compared to pre-treatment values (1.64±0.24x10⁻³ mm²/s), indicating tissue damage.
• No statistical difference in ADC reduction was found between cryoablation and HIU ablation.
• ADC values increased over time, suggesting tissue regeneration and remodeling post-ablation.

Conclusions:

• DWI is a promising technique for monitoring prostate thermal therapies.
• ADC changes provide insights into tissue damage and remodeling after thermal injury.
• Early ADC decrease may complicate DWI-based thermometry but overall DWI shows potential for viability assessment.