Central Vestibular Disorder & Its Types

Central Vestibular Disorder

• Not all vertigo results from a peripheral vestibulopathy and may actually be secondary to central pathology.

  

  Fig.1: Central neuronal connection.

1. Vertebrobasilar Ischemic Stroke

1. The blood supply to the brainstem, cerebellum, and inner ear is derived from the vertebrobasilar system.
2. Occlusion of any of the major branches [anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA), and vertebral artery] may result in vertigo.
3. Causes:
1. Atherosclerosis
2. Embolism
3. Vertebral artery dissection
4. Subclavian steal syndrome
5. Hypercoagulation disorder
6. Inflammatory conditions.
4. The symptoms associated with ischemic stroke are dependent upon which branch of the system is occluded.
1. Occlusion of Posterior Inferior Cerebellar Artery (PICA) will cause Lateral Medullary Infarction and result in Wallenberg's syndrome/lateral Medullary syndrome and characterized by:
1. Vertigo
2. Nystagmus
3. Gait disturbance
4. Ipsilateral limb ataxia 
5. Facial pain or numbness
6. Contralateral body hemianesthesia
7. Horner's syndrome
8. Dysphagia
9. Hoarseness
10. Facial nerve paralysis
2. Occlusion of Anterior Inferior Cerebellar Artery (AICA) will cause lateral pontomedullary infarction and result in lateral inferior pontine syndrome.
1. This syndrome is characterized by symptoms similar to Wallenberg's syndrome.
2. Involvement of 8th & 7th cranial nerves results in ipsilateral facial paralysis and tinnitus and hearing loss. 
3. Dysphagia and hoarseness, however, are not apparent as 9th and 10th cranial nerve nuclei are uninvolved with occlusion of the anterior inferior cerebellar artery.
3. Occlusion of the vertebral artery may affect the cerebellum only. Sign and symptoms are:
1. Mimic a peripheral vestibular hypofunction.
2. Dysdiadochokinesia
3. Past pointing (inability to place a finger or some other part of the body accurately on a selected point).
5. Patients with transient ischemic attack may present with sudden vertigo that last minutes and complaint of hearing loss.

2. Vertebrobasilar Insufficiency (VBI)

1. Vertebrobasilar insufficiency is synonymous with a transient ischemic attack (TIA) of the vertebrobasilar system. 
2. The symptoms resolve within 24 hours. 
3. If left untreated, the disease process will progress to stroke with permanent or long-lasting consequences.
4. Causes:
1. Motor vehicle accident (MVA)
2. Cervical spondylosis
5. Symptoms:
1. Visual field cuts [loss of peripheral vision (Hemianopia)]
2. Visual dysfunction
3. Drop attacks (sudden, spontaneous falls)
4. Incoordination
6. Symptoms may last from minutes to hours in duration.

4. Multiple Sclerosis

1. MS can affect the 8th cranial nerve where it enters the brainstem.
2. Sign and symptoms are identical to unilateral vestibular hypofunction (UVH).
3. Diagnosis: MRI

5. Migraine-Related Dizziness

1. Migraine related symptoms include: 
1. Vertigo, 
2. Dizziness, 
3. Imbalance, and 
4. Motion sickness.
2. A recent study reported 100% of migraineur's head abnormal nystagmus during a migraine episode if they were positionally tested as a part of the oculomotor examination.
3. Vestibular rehabilitation in patients with migraines can be very helpful but patients with both vestibular hypofunction and migraine do not respond as well.

Cervicogenic Dizziness The condition is also known as proprioceptive vertigo, cervicogenic vertigo, and cervical dizziness. Cervicogenic dizziness is characterized by the presence of imbalance, unsteadiness, disorientation, neck pain, limited cervical range of motion (ROM), and may be accompanied by a headache. Mechanism of involvement: Disruption of the normal afferent signals from the upper cervical proprioceptors to the contralateral vestibular nucleus results in an inaccurate depiction of head and neck orientation. Vertebrobasilar insufficiency Patients suspected of having VBI should be referred to a neurologist. Repeated episodes of vertigo without the associated VBI symptoms usually suggest a peripheral vestibular diagnosis.