Fig. 5: Comparison of SNR performance of representative protocols on the Connectome 2.0 scanner. | Nature Biomedical Engineering

Fig. 5: Comparison of SNR performance of representative protocols on the Connectome 2.0 scanner.

From: Ultra-high gradient connectomics and microstructure MRI scanner for imaging of human brain circuits across scales

Fig. 5

a, Compared with the Connectome 1.0 protocol (red), the Connectome 2.0 protocol (blue) uses the higher maximal gradient strength (Gmax = 500 mT m−1) and slew rate (SRmax = 600 T m−1 s−1) to shorten the diffusion time Δ and diffusion gradient pulse width δ, leading to shorter echo times TE and higher SNR for any given diffusion weighting b-value. b, Compared with the Connectome 1.0 protocol (red), the minimal TE required to achieve a given b-value is shorter when using the Connectome 2.0 protocol (blue). The data points are the actual sequence parameters and the curves are the predictions based on a sequence simulator. c, The TE shortening enabled by the Connectome 2.0 gradients yields an SNR gain of ~1.2–2 with respect to the Connectome 1.0 protocol at the highest b-values. The data points are the SNR measurements averaged in the cerebral white matter. The curves are the theoretical prediction using a mono-exponential decay (assuming T2 = 80 ms in white matter). d, DWIs demonstrate the visible SNR gains provided by the Connectome 2.0 protocol over the Connectome 1.0 protocol for b-values from 5,000 to 40,000 s mm−2.

Back to article page