Neurol India Close
 

Figure 7: (a) Evaluation of vertebral artery groove (VAG) for determination of "safe zone": By measuring the parameter 'a' that is the vertical distance from the apex of VAG to the upper facet joint surface and parameter 'e' that is the horizontal distance from the entrance of VAG to the lateral margin of the vertebral canal; Types of VAG of axis: (b) wide with low lying VA (type 4a); and (c) narrow with high riding VA (type 4b)

Figure 7: (a) Evaluation of vertebral artery groove (VAG) for determination of