Clinical use and radiological yield of magnetic resonance fingerprinting in epilepsy

Magnetic resonance fingerprinting (MRF) is a novel paradigm for magnetic resonance imaging (MRI) that efficiently generates multiparametric quantitative tissue property maps with a single acquisition. Its quantitative nature offers many advantages over conventional MRI. Although interest in MRF for epilepsy research has grown in recent years, systematic evaluation of its radiological and clinical value as a supplementary imaging modality is limited.

We reviewed the diagnostic utility of MRF imaging for 100 epilepsy patients undergoing presurgical evaluation. MRF quantitative maps (T1, T2, gray matter fraction, and white matter fraction) were generated and reviewed alongside conventional MRI. MRF findings were classified as (1) consistent-MRF findings the same as conventional MRI; (2) additional-MRF revealed findings beyond those seen on conventional MRI; or (3) discrepant-findings on conventional MRI not reproduced on MRF. We further stratified results by radiological diagnosis or pathology if available. Observations were further classified based on whether T1 or T2 MRF maps provided greater diagnostic utility.

MRF revealed additional findings in a total of 46 patients (46/100, 46%). In one patient, findings on conventional MRI were not recapitulated on MRF (1/100, 1%). In the remaining 53 patients, MRF findings were consistent with conventional MRI (53/100, 53%). Additional benefits of MRF included the following: improved lesion conspicuity (n = 16), improved visualization of lesion extent (n = 11) or asymmetry between bilateral mesial temporal regions (n = 9), differentiation between multiple lesions (n = 5), new lesion identified (n = 2), and visualization of connection between lesion and other areas (n = 1). Added value from MRF was particularly common in patients with focal cortical dysplasia (FCD) type IIa (p = .009 vs. FCD IIb) and periventricular nodular heterotopia.

Our findings demonstrate the additional yield from MRF in the identification and definition of the extent of epileptogenic lesions, underscoring its potential as a valuable adjunct in presurgical epilepsy evaluation.