High b-Value Diffusion-Weighted Imaging on Human Spinal Cord in Vivo: Investigation of Signal Dependence on Diffusion Time

Novena Rangwala¹, David Hackney¹, David C. Alsop¹

STEAM EPI was used to acquire high b-value diffusion-weighted (DW) images on cervical spinal cord in vivo with diffusion times (Δ) of up to 1000 ms. Mono-exponential and diffusional kurtosis fitting were used to calculate parameters such as ADC and kurtosis. b~14750 s/mm² images show clear distinctions between regions within the cord, and fitted model parameters show increasing consistency (lower standard deviations) with b-range, indicating the advantage of high b-range acquisitions. Tests of statistical significance did not indicate any dependence on Δ, however a dependence of parameters on b-range was observed, suggesting the need for models that better fit the data over extended b-value range.