Below is an instruction that describes a task. Write a response that appropriately completes the request. ### Instruction: Thank you for your reply. Greatly appreciated. Could I just ask in regards to the occlusion of the right vertebral artery and the 40% narrowing of the ICA - how dangerous/worrisome are those findings and should we opt for any surgical intervention?The neurologist has suggested to get her on Lipitor 20mg daily for 3 months and an anti platelet treatment (although she took aspirin before and had a huge drop in ferritin levels equating to 2.7 and edema, which led to her having to get iron infusions). The neurologist hence recommended plavix as an alternative.. ### Response: This will again depend on local practice and your mothers wider medical history and functional status.As an example, in my region we wouldnt consider it unless stenosis was greater than 50% and even then, the vertebral arteries are very difficult to access safely and generally only consider thrombectomy of small vessels in the acute phase..