Central Causes of Dizziness
The primary central causes of dizziness include migraine-associated vertigo (vestibular migraine), vertebrobasilar insufficiency/stroke, intracranial tumors, multiple sclerosis, and cerebellar disorders. 1
Major Central Etiologies
Vascular Causes
- Vertebrobasilar insufficiency presents with isolated transient vertigo lasting less than 30 minutes without hearing loss, and can precede stroke by weeks to months 1
- Brainstem and cerebellar stroke account for approximately 3% of vertigo cases in general practice settings, though 10% of cerebellar strokes can mimic peripheral vestibular processes 1
- Cerebrovascular disorders related to the vertebrobasilar circulation represent the most common central cause of dizziness overall 2
Vestibular Migraine
- Migraine-associated vertigo accounts for approximately 14% of all vertigo cases and has a lifetime prevalence of 3.2% 1
- Diagnostic criteria require: episodic vestibular symptoms lasting 5 minutes to 72 hours, current or history of migraine, migraine symptoms during at least 50% of dizzy episodes (headache, photophobia, phonophobia, or aura), and exclusion of other causes 1
- Though heterogeneous, it is more often central rather than peripheral in nature 1
Structural CNS Lesions
- Intracranial tumors of the posterior fossa must be distinguished from peripheral causes 1
- Multiple sclerosis and other demyelinating diseases can present with vertigo as a central manifestation 1, 2
- Arnold-Chiari malformation and cerebellar degeneration are additional structural causes 3
Other Central Causes
- Neurodegenerative disorders can produce central dizziness 2
- CNS infections represent serious but less common etiologies 4
- Certain medications (Mysoline, carbamazepine, phenytoin, antihypertensives, cardiovascular drugs) can cause central-type dizziness 1
Critical Distinguishing Features from Peripheral Causes
Red Flag Nystagmus Patterns
- Downbeating nystagmus on Dix-Hallpike maneuver (particularly without torsional component) strongly suggests central pathology 1
- Direction-changing nystagmus without head position changes (periodic alternating nystagmus) indicates central origin 1
- Gaze-evoked nystagmus that does not fatigue and is not suppressed by visual fixation points to central lesions 1
- Baseline nystagmus without provocative maneuvers suggests neurologic cause 1
Associated Neurologic Signs
- Presence of dysarthria, dysmetria, dysphagia, sensory or motor deficits, or Horner's syndrome indicates posterior circulation involvement 1
- Severe postural instability and additional neurological signs help distinguish vertebrobasilar insufficiency from peripheral causes 1
- Multidirectional nystagmus not suppressed by optic fixation, along with severe ataxia, suggests central vestibular lesions affecting pons, medulla, or cerebellum 2
Clinical Pitfalls and Risk Stratification
High-Risk Patient Characteristics
- Age 60 years or older increases odds of serious neurologic diagnosis 5.7-fold 4
- Chief complaint of imbalance (rather than vertigo) increases odds 5.9-fold 4
- Any focal examination abnormality increases odds of CNS pathology 5.9-fold 4
When to Suspect Central Pathology
- Failure to respond to conservative management (canalith repositioning or vestibular rehabilitation) should raise concern for non-BPPV diagnosis, potentially central 1
- Acute vestibular syndrome (continuous dizziness lasting days to weeks) has different differential than episodic positional vertigo 1
- Central causes account for approximately one-fourth of all dizziness cases in epidemiologic studies 2