title: Relationship between T2-weighted hyperintensities (unidentified bright objects) and lower IQs in children with neurofibromatosis-1.
abstract: 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.
authors.affiliation: Kennedy Krieger Institute, Baltimore, Maryland 21205, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Denckla
authors.forename: K
authors.initials: K
authors.lastname: Hofman
authors.forename: M M
authors.initials: MM
authors.lastname: Mazzocco
authors.forename: E
authors.initials: E
authors.lastname: Melhem
authors.forename: A L
authors.initials: AL
authors.lastname: Reiss
authors.forename: R N
authors.initials: RN
authors.lastname: Bryan
authors.forename: E L
authors.initials: EL
authors.lastname: Harris
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: C S
authors.initials: CS
authors.lastname: Cox
authors.forename: L J
authors.initials: LJ
authors.lastname: Schuerholz
mesh_terms: D000293:Adolescent; D002648:Child; D006801:Humans; D008607:Intellectual Disability / Q000150:complications*; D007360:Intelligence; D008279:Magnetic Resonance Imaging; D009456:Neurofibromatosis 1 / Q000503:physiopathology* / Q000523:psychology; D012044:Regression Analysis