Navigator-Based Slice Tracking for Multiband Accelerated Liver DWI

Area of Science:

• Medical Imaging
• Radiology
• Biomedical Engineering

Background:

• Clinical liver diffusion-weighted imaging (DWI) is challenged by long scan times and respiratory motion.
• Motion artifacts degrade image quality and limit diagnostic accuracy in liver DWI.

Purpose of the Study:

• To evaluate a navigator-based slice tracking (NAV) technique for prospectively compensating respiratory motion.
• To assess the impact of NAV on image quality in multiband (MB) accelerated liver DWI.

Main Methods:

• A navigator acquisition at the diaphragm was used for real-time motion tracking.
• Multiband accelerated DWI sequences with and without NAV were compared.
• Image quality metrics including coefficient of variation (CoV), signal-to-noise ratio (SNR), and sharpness were analyzed.

Main Results:

• NAV effectively computed respiratory motion, significantly reducing CoV compared to free-breathing DWI.
• NAV improved SNR and liver sharpness, enhancing visualization of organ structures.
• Detailed anatomical structures were better delineated in patients with lesions using NAV.

Conclusions:

• Navigator-based slice tracking is a feasible technique to mitigate respiratory motion in MB accelerated liver DWI.
• NAV enhances image quality and diagnostic potential for clinical liver imaging.