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Improved T2 mapping accuracy with dual-echo turbo spin echo: effect of phase encoding profile orders
Stephan W Anderson1, Osamu Sakai, Jorge A Soto
1Department of Radiology, Boston University Medical Center, 820 Harrison Avenue, Boston, Massachusetts 02218, USA. stephan.anderson@bmc.org
Magnetic Resonance in Medicine
|March 1, 2012
Summary
Voxel-sensitivity formalism corrects T(2) errors in dual-echo Turbo Spin Echo (TSE) MRI scans. This method significantly improves T(2) accuracy, making TSE sequences more reliable for clinical use.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Biomedical Engineering
- Medical Physics
Background:
- Turbo Spin Echo (TSE) pulse sequences are used for rapid T(2) relaxation time estimation in MRI.
- T(2) estimations with TSE sequences can differ from reference standards due to errors.
- Differing phase encoding profile orders in dual-echo TSE sequences are a known source of error.
Purpose of the Study:
- To apply voxel-sensitivity formalism to correct T(2) estimation errors in dual-echo TSE sequences.
- To evaluate the accuracy of corrected dual-echo TSE T(2) values compared to a reference standard.
Main Methods:
- Dual-echo TSE and multi-echo spin-echo (32-echo) acquisitions were performed.
- The American College of Radiology phantom and human brain scans were utilized.
- T(2) estimations were compared between uncorrected, corrected dual-echo TSE, and 32-echo acquisitions.
Main Results:
- Voxel-sensitivity formalism correction significantly improved T(2) estimation accuracy in dual-echo TSE.
- Accuracy improvements ranged from 5.2% to 18.6% in brain regions and phantom analyses.
- Corrected dual-echo TSE T(2) values showed better agreement with the 32-echo reference standard.
Conclusions:
- Voxel-sensitivity formalism effectively corrects for phase encoding profile order errors in dual-echo TSE.
- This correction enhances the accuracy of T(2) relaxation time measurements using TSE sequences.
- The improved accuracy supports the clinical feasibility of TSE for reliable T(2) estimation.
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