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Updated: Jan 29, 2026

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Automated Segmentation of Cortical Grey Matter from T1-Weighted MRI Images
Published on: January 7, 2019
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Reference range determination for imaging biomarkers: Myocardial T1.
David M Higgins1, Claire Keeble2, Christoph Juli3
1MR Clinical Science, Philips UK & Ireland.
Journal of Magnetic Resonance Imaging : JMRI
|February 14, 2019
Summary
Establishing myocardial T1 reference ranges using MRI is crucial for cardiac medicine. This study presents a statistically sound method to determine these ranges, ensuring accuracy and efficient resource use for clinical comparisons.
Area of Science:
- Cardiovascular Imaging
- Biomarker Validation
- Medical Physics
Background:
- Myocardial T1 relaxation time, an imaging biomarker derived from MRI, requires validated reference ranges for effective use in cardiac medicine.
- Current consensus recommends individual centers establish their own myocardial T1 reference ranges.
- Accurate reference ranges are essential for interpreting T1 measurements in clinical practice.
Purpose of the Study:
- To outline a statistically robust methodology for establishing and reporting myocardial T1 reference ranges within individual centers.
- To minimize the risks associated with undersampling (uncertainty) and oversampling (resource waste, participant burden).
- To provide a standardized approach for generating reliable T1 reference ranges.
Main Methods:
- A cohort of 278 healthy subjects without cardiac disease was recruited from two cardiac MRI centers.
- Myocardial T1 relaxation times were measured using a Modified Look-Locker Inversion recovery sequence at 1.5T and 3T field strengths.
- Statistical analysis included Shapiro-Wilk tests for normality, Tukey's robust method for outlier identification, and reference range calculation with confidence intervals.
Main Results:
- Reference ranges for myocardial T1 were calculated with confidence intervals at both 1.5T and 3T across the two sites.
- Specific ranges were determined: 3T (site 1: 1129-1301 msec; site 2: 1160-1309 msec) and 1.5T (site 2: 933-1020 msec [male], 965-1054 msec [female]).
- The 3T reference range from site 1 was successfully validated against site 2's range, demonstrating inter-center consistency.
Conclusions:
- The described methodology enables the proper characterization of myocardial T1 reference ranges.
- This approach facilitates reliable clinical comparisons by providing reference ranges with known confidence intervals.
- The study provides a framework for centers to establish valid myocardial T1 reference ranges for diagnostic use.
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