Computed tomography--but not magnetic resonance imaging--identified periventricular white-matter lesions predict symptomatic cerebrovascular disease in probable Alzheimer's disease
O. L. Lopez, J. T. Becker, C. A. Jungreis, D. Rezek, C. Estol, F. Boller and S. T. DeKosky
Department of Neurology, University of Pittsburgh, PA, USA.
OBJECTIVE: To examine the clinical consequences of periventricular
white-matter lesions on computed tomography (CT) and magnetic resonance
imaging (MRI) scans in probable Alzheimer's disease. DESIGN: Case series,
12-month follow-up. SETTING: Multidisciplinary behavioral neurology
research clinic. PATIENTS: We longitudinally evaluated the clinical
characteristics of 27 patients with probable AD for whom both CT and MRI
scans had been performed at baseline. INTERVENTIONS: None. MAIN OUTCOME
MEASURE: The presence of abnormal neurological signs was examined at
baseline and at a 12-month examination. RESULTS: Periventricular
white-matter lesions were observed with CT in 12 patients (44%) and with
MRI in 21 patients (78%). Computed tomography did not detect lesions of 1
to 3 mm, as were seen on MRI scans, and CT also did not detect lesions of 4
to 10 mm when they occurred in the deep subcortical white matter and were
not part of a greater confluent lesion. There was no relationship between
the severity of periventricular white-matter lesions with either
neuroimaging method and the presence of abnormal neurological signs.
However, there was a greater frequency of periventricular white-matter
lesions shown on CT scans than on MRI scans at baseline in patients in whom
abnormal neurological signs (eg, abnormal gait, asymmetric deep tendon
reflexes, focal motor deficits, abnormal plantar response) developed at
12-month follow-up. CONCLUSION: Although MRI may be more sensitive in
detecting periventricular white-matter lesions, CT is more specific in
predicting subsequent symptomatic cerebrovascular disease.