Misc

Question 1

Describe the pathway of the vertebral artery

Where is it most vulnerable?

Answer 1

First branch of subclavian artery.
Courses between longus colli and anterior scalene
Enters TP of C6 & Ascends through foramina of TPs of C6 to C2
After passing through the foramen of the TP of C2, it takes a 45 degree lateral turn to reach the more laterally placed transverse foramen of C1.
Note that extension with rotation usually impairs blood flow between C1 and C2 in the vertebral artery on the opposite side
Passes through foramen of C1 posterior and medial to rectus capitis lateralis
Winds medially around superior articular process of C1 in a groove in the posterior arch, passing beneath posterior atlanto-occipital membrane (where a posterior ponticle may be present) .
Pierces dura and arachnoid and courses superiorly through foramen magnum

The vertebral artery artery is most vulnerable;

• at the acute angulation at C6-7
• to productive change in and around the intertransverse foramen of C6-1
• at the atlanto-occipital junction

Question 2

What signs and symptoms may indicate VBI?

Answer 2

If one or both vertebral arteries are damaged or occluded, placing the neck in a position, which normally causes occlusion (ie.rotation and extension), may cause brain stem ischaemia giving rise to the following signs and symptoms:

Vertigo, Visual changes (including diplopia), Nausea , Nystagmus, Numbness & Sensory disturbance , Ataxia & Drop Attacks , Tinnitus , Dysarthria & Dysphagia