Meeting Banner
Abstract #3188

Convenient B-Value and B-Matrix Computations for Arbitrary Gradient Waveforms: Characterizing Signal Decay Due to Gaussian Diffusion

Evren Ozarslan1, Thomas H. Mareci2

1Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States; 2Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, United States

Estimations of apparent diffusion coefficient (ADC) and tensor (ADT) from diffusion-weighted acquisitions necessitate computations of, respectively, the b-value and b-matrix associated with the employed pulse sequence. We show that these important quantities can be conveniently computed for any gradient waveform using a simple algorithm that requires a few lines of code. This is achieved by representing the waveform by a piecewise constant function. With this representation, our technique complements the existing methods commonly used to compute the effects of restricted diffusion, and provides a consistent and convenient framework for studies that aim to infer the microstructural features of the tissue.

Keywords

accurate algebra although amount analytical apparent application applications appropriate approximating arbitrary assess assumes attenuation basic biochemistry biology biophysical brevity carrying challenging characterizing chem choice clinical complement complete component compute computed computing concepts consistent constant contrasts controlled convenient conveniently correctness cosine decay derivations deviation diffusion distinct duration efficiently emerges employ employed encoding envision error essentially establish estimation estimations evaluating exact existing expected expression expressions extracellular function functions generator gore gradient gradients great illustrates important included incorporate incorporating induced instrument integrals intervals intracellular involves leads mathematics matrix measured medical modeling models modulated molecular need negligible note noted orientation oscillating otherwise package pairs part percent perfectly phys piecewise plot practice problem process produces profiles program pulse pulses quick radiology rapidly referred reported representing required respectively restricted scheme schemes school science shaped significantly software solution solutions solved sophisticated space studies symbolic taken tanner tend theoretical tissue traditional train unique variations waveform waveforms widely women yielding