Question
Question Posted 12/03/22:
Can you point out where to find the sequence information of MRI, and DTI for ADNI2/GO such as TE/TR, TI, and flip angle? I checked https://adni.loni.usc.edu/methods/documents/mri-protocols/, and found information only about medical systems and examed https://adni.loni.usc.edu/methods/documents/ and only found that informaton for ADNI3.
Can you point out where to find the sequence information of MRI, and DTI for ADNI2/GO such as TE/TR, TI, and flip angle? I checked https://adni.loni.usc.edu/methods/documents/mri-protocols/, and found information only about medical systems and examed https://adni.loni.usc.edu/methods/documents/ and only found that informaton for ADNI3.
Response posted 12/09/22 by Rob Reid:
Hello Amanda,
ADNI2's DTIs were GE only, with flip angle 90 degrees, had no TI, and had TE ranging from 62 (Discovery 750) to 84 (Signa HDx) ms. TR varied from 9 to 12 s, but that had no effect on the image contrast. The TR variation was partly driven by TE (which was driven by the gradient hardware), and partly by participant size or weight, as the scanners automatically adjusted TR to stay under the PNS limit.
ADNI2's DTIs were GE only, with flip angle 90 degrees, had no TI, and had TE ranging from 62 (Discovery 750) to 84 (Signa HDx) ms. TR varied from 9 to 12 s, but that had no effect on the image contrast. The TR variation was partly driven by TE (which was driven by the gradient hardware), and partly by participant size or weight, as the scanners automatically adjusted TR to stay under the PNS limit.