- Walking poster presentation
- Open Access
Pilot data of right ventricular myocardial T1 quantification by free-breathing fat-water separated dark blood saturation-recovery imaging
© Heng et al; licensee BioMed Central Ltd. 2015
- Published: 3 February 2015
- Right Ventricular
- Pulmonary Hypertension Patient
- Right Ventricular Free Wall
- Myocardial Signal
- Dark Blood
Right ventricular (RV) T1 quantification is desirable in managing congenital heart disease and pulmonary hypertension patients where RV fibrosis is implicated. RV T1 quantification is technically difficult because of the thin trabeculated mobile wall of complex geometry, impacted by adjacent blood and epicardial fat, plus proximity to sternal wires in some cases. Prior work has measured RV T1 by multi-shot segmented imaging1, further by IDEAL fat-water separation in SASHA extended to suppress blood signal by inflow of saturated blood.2 We present initial results by single-shot imaging with motion-corrected (MoCo) averaging aiming to: 1) reduce ghost artifacts arising in a segmented scan, 2) apply fat-water separation, 3) null blood within the RV, 4) facilitate anchor image acquisition and 5) permit free-breathing acquisition.
Data for five healthy volunteers was acquired during free-breathing (FB) on a 1.5T Siemens Avanto by MoCo averaging of fat-water separated single-shot scans.3 Dark blood motion-sensitized4 preparation (MSPrep) parameters and feasibility were investigated.
Optimised BIR-4 saturation efficiency η was <0.5% of M0 over typical 1.5T cardiac B0 and B1 distortion. The MSPrep aimed to null blood signal by through-slice velocity-sensitized dephasing without losing myocardial signal, by adjustable time of application and velocity-sensitivity Field-of-Speed4. Mean RV free wall and septal T1s were independently measured by two observers from 2-parameter fit pixelwise maps assuming η=1.
Myocardial T1 values in volunteers reported as mean ± standard deviation (SD) with coefficient of variation (CoV = SD/mean x100%). FB: free breathing, RV: right ventricle, LV: left ventricle
Mean T1 (ms)
Mean T1 (ms)
FB RV free wall
FB LV septum
Although FB RV T1 quantification is feasible with the proposed method, further technical development work is required and underway towards improved precision and accuracy.
British Heart Foundation, NIHR Cardiovascular Biomedical Research Unit of Royal Brompton & Harefield NHS Foundation Trust and Imperial College London.
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