Signs and Symptoms of Right Cerebellar Stroke
The most common signs and symptoms of right cerebellar stroke include dizziness, vertigo, nausea, vomiting, ataxia (particularly truncal and limb ataxia), and ipsilateral limb coordination deficits. 1
Cardinal Manifestations
Primary Symptoms
- Dizziness and vertigo: Present in up to 87% of cerebellar infarctions 2
- Nausea and vomiting: Common presenting symptoms that may mimic gastroenteritis 1
- Headache: Particularly in the occipital region 1, 3
- Gait and stance instability: Present in approximately 42% of cases 3
- Lateropulsion: Tendency to fall toward the side of the lesion, present in up to 82% of patients 2
Neurological Deficits
- Ipsilateral limb ataxia: Incoordination of the right arm and/or leg 1
- Dysarthria: Slurred speech due to impaired coordination of speech muscles 3
- Nystagmus: Involuntary eye movements, present in about 37% of cases 3
- Dysphagia: Difficulty swallowing, seen in approximately 30% of patients 3
Distinguishing Features
Cerebellar-Specific Signs
- Truncal ataxia: Often missed during bedside examination if not specifically tested 1
- Ipsilateral dysmetria: Overshooting of targeted movements on the right side
- Decomposition of movement: Breakdown of smooth, coordinated movements into component parts
- Dysdiadochokinesia: Inability to perform rapid alternating movements on the right side
Diagnostic Pitfalls
- Cerebellar infarction can be difficult to diagnose when chief complaints are dizziness, vertigo, and vomiting, which may mimic benign conditions like labyrinthitis 4
- Initial CT can be normal in up to 25% of patients 1
- Isolated vertigo or lateropulsion without other symptoms occurs in 38% of patients, leading to potential misdiagnosis 2
Warning Signs of Deterioration
Signs of Progressive Swelling
- Decreased level of consciousness: Most reliable clinical indicator of tissue swelling 1
- Ophthalmoparesis: Impaired eye movements due to pontine compression 1
- Breathing irregularities: Can occur with progressive brainstem compression 1
- Cardiac dysrhythmias: May develop as brainstem compression worsens 1
Late Signs (Medical Emergency)
- Pontine compression
- Acute hydrocephalus due to fourth ventricle obstruction
- Hypertension and bradycardia (Cushing's response)
- Respiratory irregularities progressing to respiratory arrest 1
Anatomical Correlations
Different areas of the right cerebellum produce specific symptoms when affected:
- Nodulus involvement: Associated with contralateral lateropulsion 2
- Posterior paravermis lesions: Independently associated with lateropulsion 2
- Pyramis lobule lesions: Associated with nystagmus 2
- Anterior paravermis lesions: Associated with dysarthria and limb ataxia 2
Clinical Course
- Peak swelling typically occurs several days after the onset of ischemia 1
- Neurological deterioration usually occurs within 72-96 hours in most patients 1
- Some patients may experience delayed deterioration at 4-10 days 1
- Risk of hemorrhagic transformation, which can worsen symptoms and cause sudden rapid decline 1
Diagnostic Considerations
- MRI of the head is the preferred initial imaging modality for evaluation of cerebellar ataxia 1
- Initial CT can miss early-stage posterior fossa ischemia 5
- Careful attention to speech, gait, coordination, and eye movements is required to make the diagnosis 1
Remember that cerebellar stroke can present with variable and sometimes subtle symptoms. The combination of vertigo, ataxia, and nausea/vomiting should raise suspicion for cerebellar stroke, particularly when these symptoms are accompanied by headache or other neurological deficits.