Computed tomograms (CT) demonstrated symmetrical low-density lesions in the white matter of the posterior portion of the cerebral hemispheres in a 9 yr old boy with adrenoleukodystrophy (Schilder''s disease). Biopsy of the brain in an area that appeared normal on the CT scan showed profound loss of myelinated fibers and oligodendroglia; the white matter had been replaced by a rather loose acellular stroma consisting of astroglial cells and blood vessels.