What are the symptoms of a tiny chronic left cerebellar hemisphere infarct in a patient?

Symptoms of a Tiny Chronic Left Cerebellar Hemisphere Infarct

A tiny chronic left cerebellar hemisphere infarct may be entirely asymptomatic or cause only subtle, persistent symptoms including mild left-sided limb incoordination, slight gait unsteadiness, or residual dizziness—markedly different from acute presentations that feature severe vertigo, vomiting, and ataxia.

Understanding the Clinical Context

The symptoms of a tiny chronic cerebellar infarct differ fundamentally from acute presentations. While acute cerebellar infarctions typically present with dramatic symptoms including severe vertigo, nausea, vomiting, and marked gait instability 1, 2, 3, a small chronic infarct represents healed tissue damage where the acute inflammatory phase has resolved and compensatory mechanisms have developed.

Likely Symptom Profile

Minimal or Absent Symptoms

• Many patients with small chronic cerebellar infarcts are asymptomatic because the brain has compensated over time through neuroplasticity and the lesion is too small to cause persistent deficits 2.
• The cerebellum has significant functional reserve, and tiny lesions may not produce clinically detectable abnormalities on routine examination 4.

Subtle Coordination Deficits (If Present)

• Ipsilateral limb dysmetria (left-sided incoordination) may be the only finding, manifesting as mild clumsiness with fine motor tasks on the left side 4.
• Subtle left-sided ataxia during finger-to-nose or heel-to-shin testing may be detectable only with careful neurological examination 1, 2.
• Mild dysarthria could persist, though this is more common with superior cerebellar artery territory involvement 4.

Gait and Balance Issues

• Mild unsteadiness or slight widening of gait base may be present, particularly noticeable on uneven surfaces or in darkness 1, 2.
• Subtle truncal ataxia might be detected during tandem gait testing, though this is frequently missed on routine examination 1.
• Patients may report feeling "slightly off-balance" without frank vertigo 3.

Residual Vestibular Symptoms

• Mild positional dizziness or brief episodes of imbalance with head movements may persist, distinct from the severe rotary vertigo seen acutely 4.
• These symptoms are typically much less severe than the acute presentation where vertigo, nausea, and vomiting dominate the clinical picture 1, 3.

What You Will NOT See

Absent Acute Features

• No severe vertigo, vomiting, or nausea—these are hallmarks of acute cerebellar infarction, not chronic small lesions 1, 2, 3.
• No altered consciousness—decreased level of consciousness indicates acute swelling or brainstem compression, not a tiny chronic infarct 1.
• No signs of brainstem compression such as abnormal eye movements (ophthalmoparesis), pupillary changes, or breathing irregularities 1.

No Life-Threatening Complications

• Complications like obstructive hydrocephalus, pontine compression, or mass effect occur with large acute infarcts, not tiny chronic ones 1, 3.
• Peak swelling occurs days after acute ischemia; a chronic infarct has already passed this critical window 1.

Clinical Examination Pearls

Key Assessment Points

• Carefully assess coordination with finger-to-nose and heel-to-shin testing on the left side, looking for subtle dysmetria 2.
• Perform tandem gait testing, as truncal ataxia is commonly missed during routine examination 1.
• Evaluate eye movements for subtle nystagmus, though this is less likely with a tiny chronic lesion 1, 2.
• Test for ipsilateral axial lateropulsion (tendency to fall toward the left side) 4.

Common Pitfall

• The most common error is over-attributing symptoms to a tiny chronic infarct found incidentally on imaging 2. Many small chronic cerebellar lesions are discovered incidentally and are not the cause of current symptoms—always correlate imaging findings with clinical presentation temporally and anatomically.

Diagnostic Considerations

• Initial CT can miss cerebellar infarcts in up to 25% of cases acutely, but a chronic infarct should be visible as a hypodense area on CT or a cavitated lesion on MRI 1.
• The presence of a tiny chronic left cerebellar infarct on imaging warrants investigation for the underlying vascular cause (atherosclerosis, cardioembolic source, small vessel disease) to prevent future strokes, even if currently asymptomatic 2, 5.