On 2015 Mar 10, Ben A Inglis commented:

The parameters for the magnetization preparation (MP) RF pulse are not given in the paper, the supplemental material nor in the authors' previous work (Franklin et al 2013, Franklin et al 2014) on blood flow effects in gray matter measured with MP-RAGE. Was a non-selective or slab-selective inversion pulse used? The latter is expected to have more flow weighting than the former. Also, what was the inversion time (TI)? The value of TI will also influence flow weighting. In this report as well as the two prior reports, the TR quoted is considerably shorter than the TR typically employed when using a TI of 700-900 ms at 3 T. Was the magnetization preparation actually enabled? Finally, given that the paper contends there is an effect of blood flow in assessing gray matter with MP-RAGE, discussion of the effects of the MP scheme on flow weighting is essential. As given the paper fails to explain the mechanism of the blood flow weighting and whether there might be ways to minimize effects, e.g. by using a non-selective inversion and particular inversion times.

On 2015 Mar 10, Ben A Inglis commented:

The parameters for the magnetization preparation (MP) RF pulse are not given in the paper, the supplemental material nor in the authors' previous work (Franklin et al 2013, Franklin et al 2014) on blood flow effects in gray matter measured with MP-RAGE. Was a non-selective or slab-selective inversion pulse used? The latter is expected to have more flow weighting than the former. Also, what was the inversion time (TI)? The value of TI will also influence flow weighting. In this report as well as the two prior reports, the TR quoted is considerably shorter than the TR typically employed when using a TI of 700-900 ms at 3 T. Was the magnetization preparation actually enabled? Finally, given that the paper contends there is an effect of blood flow in assessing gray matter with MP-RAGE, discussion of the effects of the MP scheme on flow weighting is essential. As given the paper fails to explain the mechanism of the blood flow weighting and whether there might be ways to minimize effects, e.g. by using a non-selective inversion and particular inversion times.