Application of Anti-Motion Ultra-Fast Quantitative MRI in Neurological Disorder Imaging: Insights From Huntington's Disease.

Background: Conventional quantitative MRI (qMRI) scan is time-consuming and highly sensitive to movements, posing great challenges for quantitative images of individuals with involuntary movements, such as Huntington's disease (HD).

Purpose: To evaluate the potential of our developed ultra-fast qMRI technique, multiple overlapping-echo detachment (MOLED), in overcoming involuntary head motion and its capacity to quantitatively assess tissue changes in HD.

Study type: Prospective.

Phantom/subjects: A phantom comprising 13 tubes of MnCl₂ at varying concentrations, 5 healthy volunteers (male/female: 1/4), 22 HD patients (male/female: 14/8) and 27 healthy controls (male/female: 15/12).

Field strength/sequence: 3.0 T. MOLED-T2 sequence, MOLED-T2* sequence, T2-weighted spin-echo sequence, T1-weighted gradient echo sequence, and T2-dark-fluid sequence.

Assessment: T1-weighted images were reconstructed into high-resolution images, followed by segmentation to delineate regions of interest (ROIs). Subsequently, the MOLED T2 and T2* maps were aligned with the high-resolution images, and the ROIs were transformed into the MOLED image space using the transformation matrix and warp field. Finally, T2 and T2* values were extracted from the MOLED relaxation maps.

Statistical tests: Bland-Altman analysis, independent t test, Mann-Whitney U test, Pearson correlation analysis, and Spearman correlation analysis, P < 0.05 was considered statistically significant.

Results: MOLED-T2 and MOLED-T2* sequences demonstrated good accuracy (Meandiff = - 0.20%, SDdiff = 1.05%, and Meandiff = -1.73%, SDdiff = 10.98%, respectively), and good repeatability (average intraclass correlation coefficient: 0.856 and 0.853, respectively). More important, MOLED T2 and T2* maps remained artifact-free across all HD patients, even in the presence of apparent head motions. Moreover, there were significant differences in T2 and T2* values across multiple ROIs between HD and controls.

Data conclusion: The ultra-fast scanning capabilities of MOLED effectively mitigate the impact of head movements, offering a robust solution for quantitative imaging in HD. Moreover, T2 and T2* values derived from MOLED provide powerful capabilities for quantifying tissue changes.

Plain language summary: Quantitative MRI scan is time-consuming and sensitive to movements. Consequently, obtaining quantitative images is challenging for patients with involuntary movements, such as those with Huntington's Disease (HD). In response, a newly developed MOLED technique has been introduced, promising to resist motion through ultra-fast scan. This technique has demonstrated excellent accuracy and reproducibility and importantly all HD patient's MOLED maps remained artifacts-free. Additionally, there were significant differences in T2 and T2∗ values across ROIs between HD and controls. The robust resistance of MOLED to motion makes it particularly suitable for quantitative assessments in patients prone to involuntary movements.

Level of evidence: 2 TECHNICAL EFFICACY: Stage 1.