Mobile Clinical Research

National Institute Of Neurological Disorders And Stroke

Investigators

Abstract

The Mobile Clinical Research (MCR) program developed a protocol to evaluate the use of pULF-MRI for studying brain morphology, pathology, and disease progression. This comparative pilot study aims to create a scientific framework for future field studies, enabling collaborators to test the utility of point-of-care MRI in their patient cohorts. The protocol, titled "Ultra-Low Field (ULF) Point-of-Care (POC) MRI System for Brain Morphology and Pathology" (NCT06203626), has enrolled 50 participants, including healthy controls and individuals with various neurological conditions such as stroke, neurodegenerative diseases, brain tumors, and cerebellar ataxia. We collected data using ultra-low-field MRI, standard MRI, and optical coherence tomography. Our analysis focuses on two main areas: the use of pULF-MRI for studying brain atrophy, and assessing the usefulness of contrast agents during pULF-MRI. pULF-MRI for study of brain atrophy: This study explored the use of portable ultra-low field (pULF) MRI as an alternative to high-field MRI (3T) for detecting brain atrophy in neurodegenerative diseases. High-field MRI is the standard but is often inaccessible outside urban centers. We conducted a prospective, cross-sectional study with 44 adults, including patients with neurodegenerative diseases, subacute stroke, cerebellar ataxia, and healthy controls. Participants underwent both 3T and pULF MRI with T1-weighted imaging. Morphometric data for cortical gray matter, white matter, ventricles, and cerebellum were extracted using AI-based segmentation tools for pULF images and conventional methods for 3T images. Correlation analyses showed high agreement between pULF and 3T volumetric measures. K-means clustering and logistic regression models were used to identify brain atrophy and differentiate pathology-related from age-related atrophy, with comparable performance between pULF and 3T MRI. The study concludes that pULF MRI produces reliable data similar to 3T MRI for identifying brain atrophy, making it a promising alternative for clinical research and care in neurodegenerative diseases. Contrast agents and pULF-MRI: This study investigated the effectiveness of portable ultra-low-field (pULF) MRI scanners, which operate at magnetic fields below 100 mT, in detecting diagnostically useful contrast enhancement patterns compared to the standard 3-tesla (3T) MRI. The research focused on five neurological conditions: meningiomas in a patient with neurofibromatosis type 2, an incidental meningioma, CNS non-TB mycobacterial infection, an oligodendroglioma repeat resection site, and a chronic subdural hematoma. Using gadolinium-enhanced (Gd+) T1-weighted (T1w) and T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) imaging, the study found that pULF-MRI could detect enhancement in larger meningiomas (≥1.5 cm) but was less effective for smaller or calcified lesions and smaller dural tails (≤0.7 cm). In the case of intracranial tuberculomas, Gd+ pULF-T1w showed nonspecific lesion enhancement, while Gd+ pULF-T2-FLAIR better delineated perilesional edema. For the oligodendroglioma resection site, pre-contrast pULF images identified key features like encephalomalacia and residual non-enhancing tumor, with Gd+ scans providing additional diagnostic utility comparable to 3T MRI. Lastly, Gd+ pULF images effectively captured enhancement of a chronic subdural hematoma, visible even on pre-Gd images. Selecting and validating appropriate use cases for contrast administration with pULF-MRI can enhance diagnostic capabilities in settings where access to standard MRI is limited or contraindicated, potentially improving neurological health outcomes.