Smoker’s disease is a relatively rare cerebrovascular disease that results from chronic progressive narrowing of the major arteries of the brain, which subsequently leads to the formation of an abnormal vascular network at the base of the skull. Smoldering disease usually involves both sides, but of course some are unilateral. So what is the difference between bilateral and unilateral smoker’s disease? Our brain has two hemispheres, and the same cerebral blood vessels are symmetrically distributed on both hemispheres. In unilateral smog, only one side of the brain is affected, and only one side is involved in the symptoms. However, the treatment of smog, whether unilateral or bilateral, requires prompt surgical intervention. In the case of unilateral smog, only one surgery is required to reconstruct the cerebral vessels on the affected side, while in the case of bilateral smog, two surgeries are required to reconstruct the cerebral vessels on both sides, with an interval of about three months between surgeries. For example, direct bypass surgery has limited scope to improve blood supply, while patch surgery is slow to take effect, usually taking 3 months to 6 months to generate new blood vessels, during which time it is still very dangerous and cerebral infarction or cerebral hemorrhage may occur at any time. Combined vascular bypass surgery is now a new and very effective surgical procedure for the treatment of smoker’s disease, which combines both direct bypass and patching in a single procedure, with a two-pronged approach to achieve more desirable results.