What the new study measured
Researchers from NYU Grossman School of Medicine, working with Siemens Healthineers, pulled sequence-level analytics from scanner log files across 85,300 MRI exams over a six-month period and published the results in the Journal of the American College of Radiology, as reported by Radiology Business and The Imaging Wire.
About 4.8% of all exams — roughly 4,000 — included at least one sequence repeated because of patient motion. Motion-driven repeats consumed about 115 additional scanner hours over the six months, which the study equates to roughly 268 lost MRI appointment slots — capacity that never went to a new patient.
The repeat rate wasn't uniform across exam types. Pediatric imaging had the highest rate, at 9.9% — unsurprising, given how hard it is to keep a young child still for several minutes — while breast MRI had the lowest, at 3.5%.
A repeat doesn't always fix the problem
The study went a step further than counting repeats — it asked whether they were worth it. In a brain MRI sub-analysis covering 77 patients, repeats generally did improve image quality and diagnostic confidence, in about 80% of cases. Read the flip side of that number: roughly one in five repeat sequences didn't improve anything, meaning the scanner time was spent twice for no clinical gain.
A smaller MRCP sub-analysis, covering 27 patients, found repeats were less successful still — quality and diagnostic confidence did not significantly improve overall. Some of the "fix" for motion waste is itself waste.
The number behind the number: $115,000 a year, per scanner
The dollar figure attached to MRI motion waste didn't come from the new study — it comes from an older, separate analysis that keeps getting cited because nothing has replaced it. In 2015, University of Washington researchers reviewed 192 clinical MR exams from a single week and modeled the cost of motion artifacts at roughly $592 per hour of lost scanner revenue — equivalent to about $115,000 per scanner per year (sensitivity range about $92,600–$139,000), a figure Radiology Business covered under the headline "$115,000 problem" and one later repeat-sequence research has continued to reference.
That 2015 study found significant motion artifacts on sequences in 7.5% of outpatient exams versus 29.4% of inpatient and emergency-department exams — and that roughly 20% of all exams needed at least one repeated sequence. The new 85,300-exam study's 4.8% repeat rate is markedly lower, which the authors attribute in part to newer acquisition technology — shorter protocols, parallel imaging, and better reconstruction — that makes scans less vulnerable to a fidgeting patient in the first place. Improvement, but not elimination: motion waste is smaller than a decade ago, not gone.
Acquisition-side waste vs. reporting-side waste
Motion repeats are easy to quantify because the unit of waste is obvious: a sequence either has to run again or it doesn't, and that shows up as minutes on a specific scanner. Reporting-side waste doesn't have that clean unit. A study that sits in a backlog, gets flagged for a second read, comes back for an addendum, or simply waits its turn on an overloaded worklist doesn't register as "115 hours on Scanner 3" — it registers as turnaround time and radiologist hours, spread across a department instead of a single machine. That makes it harder to isolate. It doesn't make it smaller.
| Dimension | Acquisition-side (motion repeats) | Reporting-side (backlog, re-reads) |
|---|---|---|
| Unit of waste | Scanner minutes, per machine | Radiologist hours, spread across a worklist |
| Quantified how | 115 scanner-hrs / 268 slots over 6 months (85,300 exams) | No equivalent per-unit figure in routine use |
| Modeled dollar cost | ~$115K per scanner per year (2015 estimate) | No comparable per-radiologist or per-worklist figure exists |
| Fix being engineered | Sequence-level log analytics, motion-robust acquisition | AI-drafted reports, worklist prioritization — newer, less uniform |
Acquisition-side figures per the studies cited above. Reporting-side cells describe the state of measurement, not a competing dollar figure — no single study has priced both sides of the pipeline at once.
Fixing the scanner doesn't shrink the queue
Fixing acquisition-side waste is worth doing on its own terms — fewer repeats means less time in the bore and more available slots. But it doesn't reduce the total amount of reporting work; it just gets more exams to that stage faster. xAID has made a version of this point before, in the context of acquisition-speed AI: a 37-hospital system that cut MRI wait times by more than 60% with faster scanning didn't reduce the number of studies that eventually needed a radiologist's read — it moved the bottleneck downstream. Better motion handling would do the same: saved scanner hours become more completed exams, all of which still have to be read.
Capacity planning that stops at the scanner — much like equipment-side disruptions to imaging capacity more broadly — is only modeling half the pipeline. The other half is the queue of studies waiting to be read, and it deserves the same per-unit rigor motion research has applied to scanner minutes.
Where xAID fits — and where it doesn't
To be direct about scope: xAID's AI CT reporting has nothing to do with the acquisition-side problem this research describes — that's an MRI protocol and hardware question, and the right fixes are motion-robust sequences, better patient prep, and log-file analytics like the study above, not a report-drafting tool. xAID's footprint is the other half of the pipeline: once a CT study is acquired, its AI drafts a structured report, an in-house radiologist reviews every preliminary, and the result is delivered ready-to-sign for the reading radiologist. Fix the acquisition-side waste with better protocols and motion correction; let AI absorb the reporting-side surge that follows. Both halves of the pipeline lose money today — treating only one of them doesn't make the imaging center whole.
Frequently asked questions
What did the new 2026 study find about motion-related repeat MRI sequences?
Researchers from NYU Grossman School of Medicine, working with Siemens Healthineers, analyzed sequence-level scanner log files across 85,300 MRI exams over six months and published the results in the Journal of the American College of Radiology. About 4.8% of exams — roughly 4,000 — included at least one sequence repeated for motion, consuming about 115 additional scanner hours, equivalent to roughly 268 lost MRI appointment slots. Pediatric MRI had the highest repeat rate at 9.9%; breast MRI had the lowest at 3.5%.
Do repeat MRI sequences actually fix the motion artifact?
Not always. In the study's brain MRI sub-analysis (77 patients), repeats improved image quality and diagnostic confidence in about 80% of cases — meaning roughly one in five repeats didn't help. A smaller MRCP sub-analysis (27 patients) found repeats were less successful, without a significant overall improvement in image quality or confidence.
How much does MRI motion artifact cost an imaging center per year?
A separate, earlier analysis by University of Washington researchers, published in JACR in 2015, reviewed 192 clinical MR exams from a single week and modeled the cost of motion artifacts at roughly $592 per hour of lost scanner revenue — equivalent to about $115,000 per scanner per year (sensitivity range about $92,600 to $139,000). That study found significant motion artifacts on sequences in 7.5% of outpatient exams and 29.4% of inpatient/emergency-department exams, with about 20% of all exams needing at least one repeated sequence.
Why isn't reporting-side waste measured the same way as scanner-side motion waste?
Motion repeats have an obvious per-unit measure: a sequence either reruns or it doesn't, and that shows up as minutes on a specific scanner. Reporting-side waste — backlog, re-reads, addenda, turnaround delay — is spread across radiologist hours and a shared worklist instead of one piece of equipment, so it rarely gets tracked with the same per-unit rigor. That makes it harder to attribute, not smaller.
Source: NYU Grossman School of Medicine / Siemens Healthineers study, Journal of the American College of Radiology (2026), as reported by Radiology Business and The Imaging Wire. Per-scanner cost estimate from Andre et al., Journal of the American College of Radiology (2015), also covered by Radiology Business. Figures are rounded as reported.