Thirteen years longitudinal study of computed tomography, visual electrophysiology and neuropsychological changes in...

The aim of the study was to determine whether CT, visual electrophysiology and neuropsychological changes could assist with the detection of pre-clinical Huntington's chorea (HC). It was also hoped that the examination protocol would be of use in patients with early symptoms or signs of disease but with no family history of HC. Twenty-three patients with HC and 45 subjects at 50% risk, were studied serially. Each visit normally entailed a CT study without intravenous contrast, visual evoked response and eye movements studies, as well as a comprehensive psychiatric, neurological and neuropsychological assessment. Over the 13 years of the study 5 persons, initially symptom free on clinical grounds, developed HC. Of these, 3 had had early atrophy of the caudate nucleus on the first visit and 4 had shown abnormalities in the visual electrophysiology before becoming symptomatic. It is concluded that CT, visual electrophysiology and neuropsychological assessment may assist in the pre-clinical diagnosis of the at-risk HC subject and in the management of the early clinical case.