Motion-Related Repeat MRI Sequences in a High-Volume Health System: Operational Burden and Heterogeneous Diagnostic Benefit.

OBJECTIVE: To quantify the operational burden of motion-related repeat MRI sequences across a high-volume health system and evaluate whether repeat acquisitions improve image quality and confidence in brain MRI and magnetic resonance cholangiopancreatography (MRCP). METHODS: This retrospective study analyzed six months of MRI examinations on scanners with sequence-level analytics. Examinations with technologist-labeled repeated sequences were identified. Brain MRI and MRCP baseline-repeat pairs were evaluated by four and two readers, respectively. Readers scored image quality and diagnostic confidence and indicated whether another repeat would be requested. Scores were compared using linear mixed-effects models with patient-level random intercepts. RESULTS: Among 85,349 MRI examinations, 4,072 (4.8%) included at least one repeated sequence. Repeat frequency was highest in pediatrics (9.9%) and lowest in breast MRI (3.5%). In the brain MRI study, 87 baseline-repeat pairs from 77 patients were evaluated. Repeat acquisition significantly improved image quality and diagnostic confidence across all metrics (all p<0.001). 19.5% of repeat sequences did not improve. Improvement declined with greater elapsed examination time. In the MRCP study, 30 baseline-repeat pairs from 27 patients were evaluated. Repeat acquisition did not significantly improve image quality or diagnostic confidence, and both readers would have requested another repeat for half of repeated acquisitions. DISCUSSION: Motion-driven repeat MRI sequences impose measurable operational burden, but diagnostic yield varies substantially by anatomic region and sequence type. Brain MRI repeats generally improved image quality and diagnostic confidence, whereas MRCP repeats showed limited benefit. These findings support sequence-level tracking to guide targeted motion-mitigation strategies and reduce low-value repeat imaging.