Relationship between T2-weighted hyperintensities (unidentified bright objects) and lower IQs in children with neurofibromatosis-1

Am J Med Genet. 1996 Feb 16;67(1):98-102. doi: 10.1002/(SICI)1096-8628(19960216)67:1<98::AID-AJMG17>3.0.CO;2-K.


To address the controversy regarding the relationship between cognitive impairment (lowering of IQ) and magnetic resonance imaging (MRI) characteristics (T2-weighted hyperintensities or unidentified bright objects [UBOs]) in children with neurofibromatosis-1 (NF-1), we used a pairwise NF-1/ sibling design; we set out to predict the lowering of IQ in each child with NF-1 as a discrepancy from the IQ of an unaffected sibling (D-SIQ). Our multiple regression model included the age of the child with NF-1, familial or sporadic nature of the NF-1, number of locations in the child's brain occupied by T2-weighted hyperintensities (UBOs), and the volumetric percentage of brain tissue occupied by T2-weighted hyperintensities (UBOs). Only the number of locations occupied by UBOs accounted for IQ lowering (D-SIQ) in children with NF-1 (42% of the variance in D-SIQ). This is the first report to confirm that a continuum of lowered IQs in NF-1-affected children exists in relation to the distribution of UBOs (range 0-7), not just presence (vs. absence) of any UBOs.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Child
  • Humans
  • Intellectual Disability / complications*
  • Intelligence
  • Magnetic Resonance Imaging*
  • Neurofibromatosis 1 / physiopathology*
  • Neurofibromatosis 1 / psychology
  • Regression Analysis