Cranial computed tomography in old age psychiatry

I read with interest Dr Fielding’s paper on the value of cranial computed tomography in old age psychiatry (Psychiatric Bulletin, January 2005, 29, 21-23). In a similar audit in the old age psychiatry service in southeast Hertfordshire, exploring the role of neuroimaging in the investigation of dementia, of 88 patients, who had undergone computed tomography or magnetic resonance imaging of brain, two were reported to have potentially reversible causes of dementia. One showed a meningioma that was considered to be an incidental finding and not causally related to dementia. The other had disproportionately dilated ventricles, suggestive of normal pressure hydrocephalus. However, this diagnosis was not confirmed on subsequent review. There were 17 patients with other focal abnormalities: 14 showed old infarcts, not suspected from the clinical history in four; two patients had focal frontal atrophy, which was unsuspected in one prior to the scan; one patient had cavum septum pellucidum and basal ganglia calcification. Although the scans led to a revision of the aetiology of dementia in some cases, the impact on subsequent management was not significant. Although this audit was conducted in a smaller sample, its findings are largely in agreement with the results of Dr Fielding.