For a longitudinal study investigating the effect of several therapies on the neurodevelopment of neonates we are looking for an optimal protocol to perform tractography and quantitative diffusion measurements on neonates. The available acquisition time would be around 6 minutes and multiband acquisition is possible.
I read on the dHCP protocol (20 b=0, 64 x b = 400, 88 x b=1000 and 128 x b=2600 s/mm2) yet with 20 minutes acquisition time (multiband 4) that would be too extensive for the allotted time.
We’re currently thinking to go for just the b=0 and b=1000 shells of the dHCP protocol. From @ThijsDhollander 's impressive presentation at ISMRM (see here) this seems to allow acceptable FODs in regions of crossing fibers. That would allow us to do connectivity and DTI analysis which would already be very valuable.
Would this approach be reasonable? Would an additional shell be useful for tractography? Besides (potential) benefits for tractography it would allow higher order models such as DKI or NODDI, yet will likely increase the scan time too much.
Looking forward to your insights.,