[Freesurfer] mri_convert problem

Hi,

I'm trying to run mri_convert to convert CT dicoms into nifti format but I keep getting the following error:

[multnomah:CT] (nmr-std-env) mri_convert -i 1.2.840.10008.5.1.4.1.22342498128.100.dcm -o ct.nii mri_convert -i 1.2.840.10008.5.1.4.1.22342498128.100.dcm -o ct.nii file not found or unknown file type for file 1.2.840.10008.5.1.4.1.22342498128.100.dcm

I'm running this from /autofs/space/multnomah_002/users/Cashlab/MG13/CT. I think the sources and directory are OK because I ran mri_convert to convert this same subject's MRI into mgz without problems. Is there a problem with the dicoms format then? How can I bypass this?

Thanks!