[Abnormal findings of dichotic listening test in patients with childhood adrenoleukodystrophy].

Ten Japanese boys with childhood-onset adrenoleukoqdystrophy (ALD) were evaluated with dichotic listening test (DLT). Six cases showed abnormal findings especially of laterality index (L.I.) calculated from the score of each ear. Some of them showed no abnormal findings with other auditory examinations containing auditory brainstem responses (ABR). One patient showed abnormal L.I. of DLT at an early stage. The abnormality of laterality index was similar to the so-called "strong left-ear suppression" in patients who underwent callosotomy. Although all of these six patients had a high signal lesion at the splenium of the corpus callosum in a T3-weighted MRI sequence, it was difficult to evaluate the width of demyelinated area. DLT could detect the early damage of connecting fibers mediating inter-hemispheric transfer of auditory information, and might be a useful method for evaluating the cerebral function of auditory processing in patients with childhood ALD.