Dementia CT

Jump to navigation Jump to search


Dementia Microchapters

Patient Information

Overview

Classification

Causes

Differential Diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: ,Sabeeh Islam, MBBS[2]

Overview

A CT scan is commonly performed, although this modality (as is noted below) may not have optimal sensitivity for the diffuse metabolic changes associated with dementia in a patient who shows no gross neurological problems (such as paralysis or weakness) on neurological exam. CT may suggest normal pressure hydrocephalus, a potentially reversible cause of dementia, and can yield information relevant to other types of dementia, such as infarction (stroke) that would point at a vascular type of dementia.

In most cases, MRI is preferred over CT because it is more sensitive for a broad range of potential pathologies while avoiding exposure to potentially harmful ionizing radiation. Neuroimaging usually shows cerebral atrophy, ventriculomegaly, Ischemic cerebrovascular disease, microhemorrhages.

CT

Following changes are seen in CT of patients with dementias:

  • Cerebral atrophy is common in patients with neurodegenerative dementia but also in normal aging. Atrophy may be generalized or regionally localized. Hippocampal atrophy can be one of the earliest and most salient manifestations of Alzahiemers Dementia.[1]
  • Ventricular enlargement may occur in association with cortical atrophy and without evidence of obstruction; Also known as hydrocephalus ex vacuo
  • Focal areas of infarction and diffuse white matter ischemic changes, called leukoaraiosis can be seen on imaging.
  • Microhemorrhages can be observed with vascular anomalies, cerebral amyloid angiopathy or hypertensive microangiopathy.[2]

References

{reflist|2}} Template:WH Template:WS

  1. Neary D (November 1990). "Non Alzheimer's disease forms of cerebral atrophy". J Neurol Neurosurg Psychiatry. 53 (11): 929–31. doi:10.1136/jnnp.53.11.929. PMC 488269. PMID 2283521.
  2. Vernooij MW, van der Lugt A, Ikram MA, Wielopolski PA, Niessen WJ, Hofman A, Krestin GP, Breteler MM (April 2008). "Prevalence and risk factors of cerebral microbleeds: the Rotterdam Scan Study". Neurology. 70 (14): 1208–14. doi:10.1212/01.wnl.0000307750.41970.d9. PMID 18378884.