Differences in anti‐amyloid therapy eligibility assessment based on use of the SWI versus GRE sequence
Camilo Bermudez, Jay J. Pillai, Brian J. Burkett, Jennifer S. McDonald, Derek R. Johnson, Heather J. Wiste, Stephen D. Weigand, Clifford R. Jack, Prashanthi Vemuri, Ronald C. Petersen, Jonathan Graff‐Radford, Vijay K. Ramanan, Petrice M. CogswellAbstract
Introduction
The number of microhemorrhages (mHs) increases risk of amyloid‐related imaging abnormalities (ARIAs) in those undergoing anti‐amyloid treatments for Alzheimer's disease. It is unclear whether using different magnetic resonance imaging (MRI) sequences to detect mH would alter treatment decisions.
Methods
We retrospectively analyzed 55 adults (mean age 72.1 ± 7.1 years) evaluated for cognitive concerns who had MRI exams including both susceptibility‐weighted imaging (SWI) and gradient echo (GRE) sequences. Three neuroradiologists independently identified and then reached consensus on mH detection. Participants were classified into mH burden categories (none, 1, 2–4, ≥ 5).
Results
Readers identified 83 mHs (mean 1.51) on SWI versus 54 (mean 0.98) on GRE. Burden categories agreed in 34 (61.8%) participants, was higher on SWI in 17 (30.9%) participants, and higher on GRE in 4 (7.3%) participants,
Conclusions
Readers on average identified more mHs on SWI than GRE, altering risk categories. Prospective studies are needed to establish SWI‐based safety thresholds for anti‐amyloid therapies.