A retrospective study of neuroradiological abnormalities detected on structural magnetic resonance imaging of the brain in elderly patients with cognitive impairment.

Background: The aim of the study was to investigate the relationship between neuroradiological and clinical diagnosis in patients presenting with cognitive impairment, and also the relationship between the neuroradiological abnormalities and cognitive function as assessed by the Mini-Mental State Examination (MMSE) score.

Methods: One hundred and four elderly subjects (65 years and over) with cognitive impairment, referred to secondary hospital services and who had brain magnetic resonance imaging (MRI) scans as part of routine clinical investigations, were studied by review of their MRI scans using a standardized procedure and by examination of the case notes.

Results: In patients with a clinical diagnosis of senile dementia Alzheimer-type (SDAT), the diagnosis was reviewed in 11.1%. In patients with vascular dementia, the diagnosis was reviewed in 62. 5%. In patients without a firm clinical diagnosis, radiological features compatible with SDAT were seen in 44.4% and with vascular dementia in 27.0%. Only 2/104 patients showed a significant focal lesion on MRI. Of the variables studied (age, sex, degree of hippocampal atrophy, extent of T2 hyper-intensities, and enlargement of the sulcal and ventricular cerebrospinal fluid (CSF) spaces) only hippocampal atrophy predicted the MMSE score ( p < 0.002).

Conclusion: MRI brain scanning has an important role in aiding and refining the clinical diagnosis of cognitive impairment/dementia in the elderly.