Vertebrobasilar insufficiency

Background

Vertebrobasilar insufficiency (VBI) is characterized by diminished bloodflow through the vertebral or basilar arteries. The two vertebral arteries originally branch proximally from the subcalvian artery and travel through the vertebrae and distally join to become the basilar artery. Symptoms result from diminished circulation to the posterior brain, brainstem and cerebellum. Head-turning can cause ipsilateral vertebral artery to temporarily occlude; if the contralateral vertebral artery is stenotic, this may lead to syncope. This is also known as Bow hunter's Syndrome (2). Head extension may also provoke symptoms. Neurologic symptoms tend to not present when one vertebral artery remains patent (3).

Symptoms may result secondary to arterial plaques, arterial dissection, compressive lesions, or subclavian steal (see below). Posterior strokes encompass 20-30% of all strokes (3). Cervical ostephytes can also directly compress vertebral arteries and cause VBI symptoms (5).

Subclavian Steal phenomenon

A stenotic lesion in the subclavian, located proximal to the vertebral artery, results in reversing the flow of blood in the vertebral artery when superimposed with increased arm activity(4).

Clinical Features

Symptoms

-Numbness/tingling -Vertigo/dizziness Changes in vision -Nausea/vomiting -Weakness -Dysphagia -Dysarthria -Syncope

Differential Diagnosis

  • Labrythitis
  • Vestibular neuritis
  • Benign positional vertigo

Diagnosis

CTA or MRA of the neck/brain

Management

Medical management

  1. Lower cholesterol
  2. Control hypertension
  3. Smoking cessation
  4. Antiplatelets

Surgical management

  1. Endarterectomy
  2. Bypass grafting
  3. Stenting

Disposition

See Also

External Links

References

  1. https://www.ucdmc.ucdavis.edu/vascular/diseases/vertebrobasilar.html
  2. Go G, Hwang S-H, Park IS, Park H. Rotational Vertebral Artery Compression : Bow Hunter’s Syndrome. Journal of Korean Neurosurgical Society. 2013;54(3):243-245. doi:10.3340/jkns.2013.54.3.243.
  3. Ibrahim Alnaami, Muzaffer Siddiqui, and Maher Saqqur, “The Diagnosis of Vertebrobasilar Insufficiency Using Transcranial Doppler Ultrasound,” Case Reports in Medicine, vol. 2012, Article ID 894913, 3 pages, 2012. doi:10.1155/2012/894913
  4. Psillas G, Kekes G, Constantinidis J, Triaridis S, Vital V. Subclavian steal syndrome: neurotological manifestations. Acta Otorhinolaryngologica Italica. 2007;27(1):33-37.
  5. Smith DR, Vanderark GD, Kempe LG. Cervical spondylosis causing vertebrobasilar insufficiency: a surgical treatment. Journal of Neurology, Neurosurgery, and Psychiatry. 1971;34(4):388-392.
  6. Tintinalli