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---
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title: "Vascular Dementia"
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docid: "f59dab57-c511-4369-8fcc-592421a4b8d1"
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breadcrumbs:
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- "Brain"
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- "Diagnosis"
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- "Pathology-Based Diagnoses"
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- "Acquired Toxic/Metabolic/Degenerative Disorders"
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- "Dementias and Degenerative Disorders"
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- "Vascular Dementia"
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---
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# KEY FACTS
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- ## Terminology
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- Vascular dementia (VaD), multiinfarct dementia (MID), vascular cognitive impairment (VCI)
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- Stepwise progressive ↓ in cognitive function
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- Heterogeneous group of disorders with varying etiologies, pathologic subtypes
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- VaD often mixed etiology
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- Can occur alone or in association with Alzheimer disease
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- MID secondary to repeated cerebral infarctions
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- VaD: Dementia caused by cerebrovascular disease or ↓ cerebral blood flow
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- VCI: Cognitive impairment caused by or associated with vascular factors
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- Can occur alone or in association with Alzheimer disease (AD)
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- ## Imaging
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- General features
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- Multifocal infarcts [cortical gray matter (GM), subcortical white matter (WM)]
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- Basal ganglia (BG), pons
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- Territorial as well as lacunar lesions
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- Coexisting microvascular WM disease common
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- Multiple remote microhemorrhages
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- CT
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- Multifocal infarcts
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- Single or multiple, lacunar to territorial
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- WM hypointensities (discrete to confluent)
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- FDG PET
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- Multifocal regions ↓ metabolism in cortex, WM
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- ## Top Differential Diagnoses
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- AD
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- Frontotemporal lobar degeneration
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- CADASIL
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- Dementia with Lewy bodies
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- ## Clinical Issues
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- 2nd most common dementia (after AD)
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- Mood & behavioral changes more typical than memory loss
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- ## Diagnostic Checklist
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- Report strategically placed infarcts
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- Look for hemorrhage, DWI abnormalities
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# TERMINOLOGY
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- ## Abbreviations
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- Vascular dementia (VaD)
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- ## Synonyms
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- Multiinfarct dementia (MID)
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- Vascular cognitive disorder (VCD)
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- Vascular cognitive impairment (VCI)
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- Subcortical ischemic VaD
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- Poststroke dementia
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- ## Definitions
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- Dementia caused by cerebrovascular disease or ↓ cerebral blood flow (CBF)
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- VCI: Cognitive impairment caused by or associated with vascular factors
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- Secondary to repeated cerebral infarctions
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- Can occur alone or in association with Alzheimer disease (AD)
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- 2nd most common cause of dementia next to AD
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# IMAGING
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- ## General Features
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- ### Best diagnostic clue
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- Multifocal infarcts
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- Cortical gray matter (GM), subcortical white matter (WM)
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- Basal ganglia (BG), pons
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- Territorial as well as lacunar infarcts
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- Changes of microvascular WM ischemia common
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- ### Location
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- Typically involves cerebral hemispheres & BG
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- Usually bilateral but may be unilateral
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- ### Size
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- Vary from single to multiple, punctate to large/confluent
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- ### Morphology
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- Small infarcts are rounded or oval; large confluent abnormalities are ill defined
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- ## CT Findings
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- ### NECT
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- Hypodensity in periventricular WM
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- Cortical, subcortical, BG infarcts
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- Generalized atrophy with focal cortical infarcts typical
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- ## MR Findings
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- ### T1WI
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- Generally have hypointense BG lacunar infarcts
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- Atrophy with enlargement of ventricles & sulci
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- ### T2WI
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- Punctate or confluent regions of hyperintense WM
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- Central pontine infarcts
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- Large areas of volume loss with widened sulci
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- ### FLAIR
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- Hyperintense foci within BG
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- Multifocal diffuse & confluent WM hyperintensities
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- ### T2* GRE
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- Multiple blooming hypointensities in cortex & along pial surface
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- ### DWI
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- ↓ fractional anisotropy & ↑ ADC within lesions, normal-appearing WM (NAWM)
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- ↑ in mean diffusivity of NAWM correlates with disability found on tests of executive function
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- ### MRA
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- Most abnormalities in small arteries, generally not well seen on MRA
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- ### MRS
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- ↓ NAA in both cortical & WM regions
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- Frontal cortex NAA negatively correlated with volume of WM signal hyperintensity
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- ## Ultrasonographic Findings
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- Transcranial Doppler sonography: Pulsatility indices in large arteries ↑ compared to AD
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- ## Nuclear Medicine Findings
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- FDG PET
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- Multiple areas of hypometabolism without specific lobar predominance
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- Severity of MID neuropsychiatric symptoms correlates with extent of ↓ metabolism in cortex & WM
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- SPECT
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- Iodine-123-iodoamphetamine: ↓ frontal & BG CBF, which correlates with low cognitive scores
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- Tc-99m hexamethyl propyleneamine oxime: CBF heterogeneity more prominent in anterior portion of brain
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- Unlike pattern in AD, in which posterior abnormalities predominate
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- ## Imaging Recommendations
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- ### Best imaging tool
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- MR
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- PET/SPECT may also provide specificity
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- ### Protocol advice
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- Axial FLAIR to detect WM infarcts
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- Axial & coronal T2WI to assess regions of atrophy
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- T2* GRE/SWI to identify hemorrhage
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# DIFFERENTIAL DIAGNOSIS
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- [Alzheimer Disease](/document/alzheimer-disease/f71f5cf5-b1af-4c6d-b145-b4c10eec7b58)
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- Striking hippocampus & amygdala atrophy
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- PET: Bilateral temporoparietal hypoperfusion/hypometabolism (BG spared)
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- Often coexists with VaD
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- [Frontotemporal Lobar Degeneration](/document/frontotemporal-lobar-degeneration/49510d0e-acf7-45cb-9eb1-53f8193b0b6d)
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- Characterized by early onset of behavioral changes with intact visual, spatial skills
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- Frontal, temporal lobe atrophy
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- Marked atrophy → knife-like gyri
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- [Alcoholic Encephalopathy](/document/alcoholic-encephalopathy/88021852-b73d-4cdf-a719-dd4ae3231e45)
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- 3rd most common cause of dementia
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- Generalized > focal atrophy; superior vermis atrophy
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- [CADASIL](/document/cadasil/6b5a24c8-afd7-4106-bb4b-11421ed1592c)
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- Most common heritable cause of stroke, VaD in adults
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- Earlier age of onset
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- Imaging looks like small vessel disease
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- [Dementia With Lewy Bodies](/document/dementia-with-lewy-bodies/e8e46d1d-46d2-4e5a-880f-f025a84c5871)
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- Hypometabolism of entire brain
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- Without infarcts or significant atrophy
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# PATHOLOGY
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- ## General Features
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- ### Etiology
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- MID is usually due to multiple small infarctions
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- Infarcts involving entire major vessel territories are usually absent
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- Minority may be secondary to single or few large infarctions
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- ~ 75% of all MID patients exhibit small vessel disease rather than thromboembolism
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- Growing evidence exists for involvement of cholinergic system in VaD
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- Cholinergic deficits well documented in VaD, independent of concomitant AD pathology
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- Cholinergic neuron loss in 70% of AD, 40% of VaD
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- ### Genetics
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- Apolipoprotein E (*APOE*)
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- Serum protein involved in lipid metabolism
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- Encoded at single gene locus on chromosome 19 by 3 alleles: ε2, ε3, ε4
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- Frequency of ε4 allele significantly higher among patients with AD & VaD compared to controls
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- Odds of developing AD or VaD are 4.4x & 3.7x higher (respectively) in presence of even single ε4 allele
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- Paraoxonase (*PON1*)
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- Component of high-density lipoproteins with antioxidative potential
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- 2 *PON1* polymorphisms (Gln192Arg associated with enzyme activity & T-107C associated with enzyme concentration) are independent risk factors for VaD, particularly in *APOE* (ε4)
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- ## Staging, Grading, & Classification
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- 8 subtypes of VaD
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- MIDs: Due to large cerebral emboli, usually readily identifiable
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- Strategically placed infarctions causing dementia
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- Multiple subcortical lacunar lesions: Develop VaD 5-25x more frequently than age-matched controls
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- Binswanger disease: Small vessel disease → widespread incomplete infarction of WM
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- Mixtures of 2 or more VaD subtypes
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- Hemorrhagic lesions causing dementia
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- Subcortical dementias due to other causes [e.g., cerebral autosomal dominant arteriopathy with subcortical infarcts & leukoencephalopathy (CADASIL)]
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- Hybrid forms of AD & VaD
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- ## Gross Pathologic & Surgical Features
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- Multifocal infarctions with atrophy
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- ## Microscopic Features
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- Arteriosclerosis & amyloid angiopathy major underlying pathologies in small vessel vascular disease
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- Vessels display atheromata, lipohyalinosis, subintimal thickening, fibrinoid necrosis
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- Infarcted tissue undergoes necrosis → gliotic wall surrounding CSF cavity
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- Myelin & axonal loss with astrocytosis
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# CLINICAL ISSUES
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- ## Presentation
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- ### Most common signs/symptoms
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- Infarcts with transient focal neurologic deficits
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- Most deficits persist
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- Mood & behavioral changes
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- Deterioration of executive function & attention, changes in personality (rather than memory loss) predominate
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- Severe depression is more common in VaD than AD
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- ### Clinical profile
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- Main risk factors
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- Advanced age, HTN, diabetes, smoking
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- Hypercholesterolemia, hypercoagulable states
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- ## Demographics
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- ### Age
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- Generally earlier age than AD
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- Incidence ↑ with age
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- ### Sex
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- M > F
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- ### Epidemiology
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- 10% of dementias
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- 2nd most common dementia (after AD)
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- ~ 25% of elderly stroke patients meet VaD criteria
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- Cerebral small vessel disease accounted for 33% of dementia risk
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- ## Natural History & Prognosis
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- Poststroke dementia: Progressive, episodic, stepwise cognitive decline following stroke
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- VaD without recent stroke: Progressive or stepwise cognitive decline without concurrent history of symptomatic stroke but with imaging evidence of clinically unrecognized cerebrovascular disease
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- Neuropsychiatric & motor signs: VaD accompanied by neuropsychiatric signs, such as depression, abulia, apathy, & psychosis with delusions or hallucinations
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- Intervals of clinical stabilization ± limited recovery
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- 5-year survival with VaD ~ 50% of age-matched controls
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- ## Treatment
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- Prevent further vascular insult
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- Control precipitating factors (e.g., HTN, diabetes)
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# DIAGNOSTIC CHECKLIST
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- ## Image Interpretation Pearls
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- Not single entity but large group of conditions with variable clinical & imaging findings
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- ## Reporting Tips
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- Report strategically placed infarcts, hemorrhagic components, DWI abnormalities, pattern of cortical volume loss if present
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6999ad9a-6bd9-47dd-8707-b571f32301e3
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