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Medical ImagingGenerated accuracy model review: 2026-05-06
MRI Scan Time accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- Time = (TR * Phase * NEX) / ETL
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Repetition Time (TR): 500 ms
- Phase Encoding Steps: 256
- NEX / NSA: 1
- Echo Train Length: 1
Expected outputs
- Scan Time: 2 min 8 sec
- Total Seconds: 128
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- The calculation is a simplified sequence-time estimate for 2D-style acquisitions and does not model every vendor-specific timing factor.
- Parallel imaging, partial Fourier, calibration scans, respiratory gating, and 3D sequence behavior can change real exam time substantially.
- This tool is best used for planning and education rather than predicting exact scanner console times.
Unit handling
- Repetition Time (TR) accepts values in ms.
- Phase Encoding Steps accepts numeric values.
- NEX / NSA accepts numeric values.
- Echo Train Length accepts numeric values.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current mri-scan-time-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for MRI Scan Time.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.