Single photon emission computerized tomography in children with developmental language disorder--a preliminary report.

Developmental language disorder (DLD) is a diagnosis given to a nonautistic child who has inadequate language acquisition despite adequate hearing, sensorimotor, and cognitive skills. We used high-resolution single photon emission computerized tomography (SPECT) with labeled technetium-99m-D, L-hexamethyl-propylene amine oxime (99mTc-HMPAO) to measure regional cerebral blood flow (rCBF) in 11 children with DLD. Their mean age was 5 years 10 months (range, 4 yr 2 mo to 10 yr 9 mo) and mean nonverbal IQ was 107 (range, 82-137). When inter-hemispheric flow discrepancy was defined as a bilateral rCBF difference of more than 10%, 10 children (90.9%) had discrepant blood flow. Temporal lobes were involved in all 10 children: lateral-temporal in five, medial-temporal in four, and mesial-temporal in four. Though the study was small and the results are preliminary, results suggest that DLD may be a consequence of an underlying neurobiologic problem in areas of the brain known to be involved with language.