Mohammed T. Abou-Saleh

252 PRINCIPLES AND PRACTICE OF GERIATRIC PSYCHIATRYFigure 48.3LeukoaraiosisFigure 48.1Multiple cortical infarctsFigure 48.2Multiple lacunaeFigure 48.4 Cortical infarcts, lacunae and leukoaraiosis coexisting in thesame patientA strategic single cortical infarct in the dominant angular gyruscan also cause a picture similar to AD with dysphasia,visuospatial disorientation, agoraphobia and memory loss. Multiplecerebral haemorrhage, which particularly occurs in cerebralamyloid, may cause dementia.While multi-infarct dementia is nearly always secondary tomultiple lesions, it is possible to see memory loss after a singleinfarct. Discrete thalamic infarction especially in the paramedianregion, may present as memory loss, often associated withsomnolence and eye movement disorders 24,25 .Lacunar InfarctionLacunae are small deep sub-cortical infarcts or haemorrhages. Asingle lacunar stroke commonly presents with pure motorhemiplegia, pure hemisensory loss or ataxic hemiparesis 21 . Multiplelacunae (e´tat lacunaire) was described by Marie to producedementia, dysarthria, small-stepping gait, incontinence andemotional lability. Fisher doubted the existence of a multi-lacunardementia, although there is now no doubt that vascular dementiadoes occur after multiple lacunar infarcts 22,23 . Lacunar infarcts arecommon in hypertension and rarely follow embolic occlusionfrom the heart or major arteries.LeukoaraiosisThis is largely a radiological diagnosis describing the diffuse orpatchy low-attenuation changes seen on CT or MRI scans in thedeep white matter 26 . Binswanger (1894) described eight patientswith slowly progressive dementia who, at post mortem, werefound to have softening and loss of deep white matter withcompensatory ventricular enlargement. There is also gliosis,thickening of the arteries, within the abnormal white matter;many also show discrete lacunar infarction, although these areoften too small to be seen on CT and MRI scanning. The