What is Binswanger's syndrome?

Binswanger's Syndrome: Clinical Features, Diagnosis, and Management

Binswanger's syndrome is a progressive form of cerebrovascular small vessel disease affecting the white matter and subcortical structures, characterized by dementia, subcortical neurological deficits, and evidence of hypertension or systemic vascular disease. 1, 2

Clinical Presentation

Binswanger's syndrome typically presents with:

• Age of onset: Sixth or seventh decade of life 2, 3
• Cognitive features:
  • Progressive dementia with prominent executive dysfunction
  • Impaired recent memory
  • Slowed information processing
  • Psychiatric manifestations (particularly depression) 2, 4
• Neurological features:
  • Subcortical deficits
  • Parkinson-like signs (rigidity, bradykinesia)
  • Gait abnormalities/dysbasia
  • Pyramidal signs
  • Pseudobulbar palsy
  • Urinary incontinence/neurogenic bladder 3, 5

Pathophysiology

The underlying pathology involves:

• Multiple small infarcts in deep white matter structures
• Diffuse cerebrovascular white matter lesions (leukoaraiosis)
• Lacunar infarcts in basal ganglia and white matter
• Blood-brain barrier dysfunction, particularly in periventricular and subcortical white matter 6
• Endothelial dysfunction with secondary inflammatory response 4
• Hypoperfusion of periventricular white matter, a watershed area irrigated by long penetrating medullary arteries 5

Risk Factors

Major risk factors include:

• Hypertension
• Systemic vascular disease
• Small-artery diseases
• Amyloid angiopathy
• Impaired autoregulation of cerebral blood flow
• Cardiac conditions (heart failure, arrhythmias)
• Hypotension 2, 5

Diagnostic Approach

Neuroimaging

• MRI (preferred modality):

  • Diffuse white matter hyperintensities on T2-weighted and FLAIR sequences
  • Attenuation of subcortical white matter (leukoaraiosis)
  • Sparing of subcortical U-fibers
  • Lacunar infarcts in basal ganglia and white matter 2, 4

• CT (less sensitive):

  • Can show leukoaraiosis but with less detail
  • Useful for excluding other etiologies 2

Clinical Assessment

• Comprehensive cognitive evaluation focusing on executive function
• Assessment for subcortical neurological signs
• Evaluation for vascular risk factors
• Exclusion of other causes of dementia and white matter disease 1, 4

Differential Diagnosis

• Other forms of vascular cognitive impairment
• Alzheimer's disease with white matter changes
• Normal pressure hydrocephalus
• Multiple sclerosis
• Leukodystrophies
• Toxic-metabolic encephalopathies 1, 4

Management Approach

Treatment is largely supportive and preventive:

1. Vascular risk factor control:

   • Aggressive management of hypertension
   • Treatment of diabetes, hyperlipidemia
   • Smoking cessation

2. Antithrombotic therapy:

   • Aspirin for secondary stroke prevention 2

3. Symptomatic management:

   • Treatment of depression with appropriate antidepressants
   • Management of gait disturbances and parkinsonism
   • Addressing urinary incontinence

4. Supportive care:

   • Social support systems
   • Discussion of advanced directives
   • Caregiver education and support 2

Prognosis

Binswanger's syndrome is typically progressive, with gradual worsening of cognitive and neurological symptoms. However, controlling vascular risk factors may help slow disease progression. The condition represents a potentially preventable form of dementia if vascular risk factors are identified and treated early 5.

Clinical Pearls

• Binswanger's syndrome is often underdiagnosed or misdiagnosed as other forms of dementia
• The presence of subcortical features (gait disturbance, urinary incontinence, parkinsonism) with vascular risk factors should raise suspicion
• White matter changes on imaging may precede clinical symptoms
• Unlike multi-infarct dementia, Binswanger's syndrome results from cortical disconnection rather than volume loss from multiple large strokes 5