FIG 2. An infant with citrullinemia (57 days).

A, Axial T1-weighted (600/16) image obtained with a spin-echo sequence and a 20-cm field of view, 256 x 192 matrix, and 5-mm contiguous sections, with the voxel location and voxel size (7.2 cm³) as indicated for proton MR spectroscopy (STEAM sequence 3000/30).

B, Proton MR spectrum obtained from the parietal white matter of an age-matched control subject (2 months). Glx = glutamine/glutamate complex, tCr = total Cr, mI = myo-inositol, other abbreviations are the same as used in the text.

C, Proton MR spectrum obtained from the parietal white matter of the patient shows a prominent increase of glutamine/glutamate and lipid/lactate complexes, and a decrease of NAA, tCr, and mI as compared with normal spectrum. The amplitude of the Cho peak is relatively well preserved.

D, A follow-up axial T1-weighted (490/14) image obtained at the age of 10 months shows severe atrophy and cystic encephalomalacia in both cerebral hemispheres