The criteria for diagnosis, treatment, family counseling and advances in genetics of neurofibromatosis are reviewed by a neurosurgeon and epidemiologist at the Massachusetts General Hospital, Boston, and the National Institute of Neurological Disorders, Bethesda, MD.
The neurofibromatoses consist of two distinct disorders, a peripheral and a central type, with genes located on separate chromosomes. The diagnosis of neurofibromatosis 1 (NF1, von Recklinghausen's neurofibromatosis or VRNF in Europe) requires two or more of the following: 6 or more cafe au lait macules, 2 or more neurofibromas, axillary or inguinal skin freckles, optic glioma, Lisch iris nodules, osseous lesion and familial occurrence. Neurofibromatosis 2 (NF2, bilateral acoustic neurofibromatosis or BANF in Europe) requires one of the following for diagnosis: a) bilateral eighth nerve tumors, or b) a positive family history plus a unilateral eighth nerve tumor or two of the following: neurofibroma, meningioma, glioma, Schwannoma, or lenticular opacity. For patients with NF2 there is a 50% risk of transmission to any offspring, and close relatives should be screened for cafe au lait spots or neurofibromas, acoustic nerve tumors and lens opacities. Acoustic neuromas commonly become symptomatic during or soon after puberty and may be exacerbated in pregnancy, suggesting a hormone or growth factor important in tumor formation. The inherited gene for NF2 is on the long arm of chromosome 22. 
COMMENT. The British Neurofibromatosis Association — LINK, and two voluntary support organizations in the US — The National Neurofibromatosis Foundation and the Acoustic Neuroma Association, organize medical symposia and provide valuable assistance to patients and their families. Newer diagnostic methods including brain-stem auditory evoked potentials, CT and MRI and routine eye examination for subcapsular cataracts should afford earlier recognition.
Unidentified bright objects (UBO's), areas of increased signal on Tl or T2 weighted MRI, with concurrent negative contrast-enhanced CT are reported in 28 children with neurofibromatosis 1 and may possibly represent heterotopias. They were not correlated with the presence of learning disorders or retardation, and their significance is unclear . I have a patient, a boy aged 12 yrs, with migraine headaches, macrocephaly, and cafe au lait patches, whose MRI shows UBO's. Although considered benign, such patients deserve careful long-term follow-up.