Presentation
Left hemifacial spasm.
Patient Data
Marked dilatation with tortuous course of the left vertebral artery is seen measuring about 6 mm in maximum caliber, reaching to the left cerebellopontine angle with subsequent displacement and compression of the left trigeminal nerve.
Dilatation and tortuous course of the basilar artery is also seen coursing towards the right cerebellopontine angle; (laterality score 3 according to Smoker's criteria - ≥2 is abnormal).
The basilar artery (BA) bifurcation is seen at the level of 3rd ventricular floor (height of bifurcation score 2 according to Smoker's criteria - ≥2 is abnormal).
Case Discussion
In this case, the basilar artery is definitely compressing the left trigeminal nerve however the ipsilateral facial nerve is not significantly displaced or compressed.