Enabling 1-minute High-resolution Clinical Diffusion-weighted Imaging at 7 Tesla via Improved Non-local-PCA Denoising

Motivation: High-resolution diffusion-weighted imaging (DWI) is crucial for diagnosing neurological pathologies, but traditionally requires long scan times due to low SNR, hindering its application in clinical settings. Goal(s): To evaluate how our new non-local principal-component-analysis (PCA)-based denoising method can help achieve high-resolution DWI at 7 Tesla within a clinically viable timeframe. Approach: We compared our method to two existing local-PCA-based approaches by collecting whole-brain DWI at 1.2-mm isotropic resolutions from a healthy volunteer and a patient with multiple sclerosis. Results: Our non-local PCA method provided improved denoising performances, producing quality DWI where the lesion was identifiable even with 1-minute acquisition. Impact: Demonstrated capable of enabling high-resolution DWI under 1-minute scan at 7 Tesla, our non-local PCA method is believed to promote the utility of DWI in clinical settings while having the potential to improve many other neuroimaging applications.