Inversion time calculations have varying impact on short, intermediate and long MOLLI T1 values: implications for studies using T1-mapping sequences
نویسندگان
چکیده
Background T1-mapping has great diagnostic potential based on tight normal ranges and excellent sensitivity to disease. Numerically, T1 calculation hinges on the inversion time (TI) from the inversion preparation to the centre of k-space for each T1-weighted image. In the original ShMOLLI sequence (Piechnik JCMR 2010, 12:69) based on “Work In Progress” WIP561 MOLLI, the TI calculation was offset from centre of k-space by two SSFP echo spacings, and included ~10ms duration of the adiabatic inversion pulse itself. The impact on T1 values resulting from rectifying this since WIP448B and WIP780 warrants investigation to assure an accurate clinical interpretation of previously published normal ranges of MOLLI T1 values.
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Are T1 values to characterize myocardial tissue equivalent between various sequences: comparison of MOLLI, shMOLLI, 3'5-MOLLI and SASHA
Background Classical modified Look-Locker sequence (MOLLI) can induce a long breath-hold and is prone to cardiac and respiratory motion. Several shorter sequences based on inversion (3’5MOLLI, shMOLLI) and saturation recovery (SASHA) of longitudinal relaxation have been proposed for derivation of T1 values or calculation of extracellular volume fraction or lambdas. Despite the validation in T1 ...
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