Hi,  <br>I am sorry to post again.   I red the old archives about dti atifacts, but  I am still not clear about artifacts in my dti data with 32 directions and 1 b0 image, which are acquired in Philips 3T sanner. <br>1) signal drop-out in axial slices  in a limit numbers of slices of a limit numbers of  gradient directions, see the attached fig1 (the right one is drop-out slice),  I am not sure that this is vibration artifact, often happened in Siemens, or head motion artifact?<br>
 2) Zebra line in cerebellum happened in most gradients directions in dti images of all the subject, see the attached fig2.  It is normal or artifacts? <br> <br>Thank you very much<br> <br>Shugao