The radiographic manifestations of neurocutaneous syndromes are reviewed from the Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, NY; and the University of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ. Tuberous sclerosis is characterized by bilateral calcified subependymal nodules on CT, and areas of hyperintensity on long TR-MRI images, representing dysplastic white matter. Neurofibromatosis Type 1 abnormalities include optic nerve glioma, hyperintense hamartomas on MR, neural foramina enlargement of the spine with or without dumbbell neurofibromas, scalloping of the posterior vertebral bodies, and kyphoscoliosis. Neurofibromatosis Type 2 has gadolinium-enhanced bilateral acoustic neuromas, schwannomas of other cranial nerves, especially trigeminal, and meningiomas; also, spinal lesions including meningiomas, schwannomas and intramedullary ependymomas and astrocytomas. Sturge-Weber syndrome diagnostic signs include CT gyriform calcification, especially parieto-occipital, ipsilateral cortical atrophy with thickening of the calvarium, prominent paranasal sinuses, elevation of petrous ridge, enlarged choroid plexus, and MRI post-gadolinium pial angiomatosis. Von Hippel-Lindau disease lesions on MRI include cerebellar hemangioblastoma (30%), mostly cystic with an enhancing mural nodule, and spinal cord hemangioblastoma (5%). Ataxia-telangiectasia is manifested on CT and MRI by progressive cerebellar atrophy, particularly the anterior vermis. 
COMMENT. This article is replete with excellent illustrations of neuroimages of neurocutaneous syndromes, essential in diagnosis. For reviews of the significance of UBOs on MRI in neurofibromatosis 1, see Progress in Pediatric Neurology III, PNB Publ, Chicago, 1997.