Meeting Banner
Abstract #2201

Monitoring of T2 with Application of Diffusion Gradients to Remove Microcirculation Contributions to Signal for Optimisation of Diffusion Protocols and Generation of Flow-Free T2 Maps

Neil P. Jerome1, James A. d'Arcy1, Matthew R. Orton1, Thorsten Feiweier2, Dow-Mu Koh3, Martin O. Leach1, David John Collins1

1Radiotherapy & Imaging, The Institute of Cancer Research, Sutton, Surrey, United Kingdom; 2Imaging & Therapy Division, Siemens AG, Healthcare Sector, Erlangen, Germany; 3Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom

Diffusion-weighted MRI in the body must account for a microcirculation fraction, separate to self-diffusion, within imaging voxels. Explicit control of diffusion pulse length and delay allows reproducible application of diffusion gradients with varying echo times; calculation of mono-exponential T2 estimates with applied gradients of b=0 and b=200 s/mm2 shows significant changes observed in liver, kidney and spleen. This suggests that the microcirculation component, with its own distinct T2, is being removed, allowing the generation of flow-free T2 maps more robustly estimating tissue T2s. This approach enables appropriate b-value choices when considering diffusion models that include or exclude microcirculation contribution.

Abstract PDF Poster PDF

Keywords

abdominal absent absorbed accomplished accurately acquisition adept allow apparent appears application applied assignment association beyond biomedical black blood breathing cancer coefficients commonly compartment compartments complex component components confound consented considered contribution contributions control curve decay decrease decreasing diffusion dispersion division drawn either eliminate england environment essentially example expected exploration exponential fast fitting five flow forms free full generate generation gives gradient gradients grants health highly house identify increasing induce inset intrinsic investigate journal kidney kingdom known ladder leach liver maps matched measure medicine model modeling monitoring mono necessarily necessitate often optimal organs perfusion phantom physiological picture plot plots potential predominantly presence print problematic produce protocol pseudo pulses radiology radiotherapy random reduce reduces reflect reflects regarding relevant removal remove robust royal sampling scanned scanner sector self simple software space spleen structure subset sufficient sufficiently suggesting support surrey systematic tandem term threshold timescale tissue unambiguously variation vary varying vascular visible volunteers whereas zero