Alzheimer's Imaging Consortium.

Area of Science:

• Neurology
• Medical Imaging
• Biotechnology

Background:

• Lecanemab, an FDA-approved Alzheimer's Disease (AD) immunotherapy, requires regular MRI monitoring for amyloid-related imaging abnormalities (ARIA).
• Current MRI protocols pose significant logistical and accessibility challenges for patients, caregivers, and healthcare facilities.
• Alternative imaging solutions are needed to facilitate wider patient access to lecanemab therapy.

Purpose of the Study:

• To evaluate the viability of an ultra-low field, portable MRI system for baseline and safety monitoring of patients undergoing lecanemab treatment.
• To assess the diagnostic performance of the portable MRI in detecting ARIA, specifically ARIA with edema (ARIA-E) and ARIA with microhemorrhage (ARIA-H).

Main Methods:

• 31 Alzheimer's Disease patients receiving lecanemab therapy or who had discontinued due to ARIA were enrolled.
• Participants underwent MRI scans using a 0.064T portable Hyperfine Swoop® system within one week of their clinical MRI scans.
• Retrospective data analysis included patient age, ARIA history, and reads from both low-field and clinical MRI scans.

Main Results:

• 100% sensitivity was achieved in detecting mild and moderate ARIA-E on the low-field MRI.
• The portable MRI system was not sensitive to ARIA-H (microhemorrhages).
• One incidental subdural hematoma, identified on a clinical scan, was also detectable on the low-field MRI.

Conclusions:

• Ultra-low field, portable MRI demonstrates high sensitivity for detecting ARIA-E, a key side effect of lecanemab.
• This technology could serve as an adequate surrogate for traditional 1.5T/3T MRI scans, potentially alleviating patient and healthcare system burdens.
• Further validation is needed to confirm its utility in routine clinical practice for lecanemab monitoring.