Vertebrobasilar Insufficiency
Overview
Vertebrobasilar insufficiency occurs when both basilar arteries are occluded.
Clinical Manifestations
The clinical manifestations of VBI are difficult to distinguish from other causes of brainstem ischemia (see later) and can include any or all of the following:
- Dizziness1
- Visual disturbance1
- Drop attacks (a sudden loss of postural tone without loss of consciousness)1
- Ataxia1
- Dysarthria1
- Dysphagia1
- Hemiplegia1
- Hemianesthesia1
- Nausea1
- Ringing in the ears1
There is no single consistent pattern for VBI1. The most common presenting symptoms are vertigo, nausea, and headache that can be subtle, intermittent, and even chronic in nature1.
Head & Neck Pain
Vertigo & Dizziness
Dizziness is the most common symptom of VBI, but is rarely found in isolation1. The dutton textbook mentions vertigo but does not provide any sources or explanation as to why this was mentioned1.
Headache
A headache due to VBI commonly manifests with a gradual onset2. The headache generally has a unilateral occipital or frontotemporal pattern1,2.
The headache is typically described as gradual onset that is mostly unilateral and involves the frontotemporal region
Other Symptoms
These signs and symptoms have been linked directly or indirectly to VBI:
- Wallenberg, horner, and similar syndromes1
- Bilateral or Quadrilateral parasthesia1
- Hemiparasthesia1
- Scotoma (a permanent or temporary area of depressed or absent vision)1
- Periodic loss of consciousness (LOC)1
- Lip/perioral anesthesia1
- Hemifacial paralysis/anesthesia1
- Hyperreflexia1
- (+) Babinski, Hoffman, or Oppenheim signs1
- Clonus1
- Gait ataxia1
- Dysphasia1
Tests
The gold standard test for VBI is conventional angiography1
Physical tests
DDX
Spontaneous intracranial hypotension is a common DDX for VBI, but differs since it generally presents with a gradual onset orthostatic headache near the occipital regions2 These headaches are orthostatic since the low volume of CSF d/t leakage allows the brain to displace downwards when standing2. This displacement causes the headache symptoms to worsen when standing and to relieve when laying down2.