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It could take up to 3-5 hours if you are having a regular craniotomy. If you have an awake craniotomy, the surgery could take 5-7 hours. This includes pre op, peri op and post op. The number one post-op concern for patients undergoing brain surgery is neurologic function.

On average, brain surgery long-term survival rate can be between 50-70% except in cases of malignant tumors where chances are lowered. In cases of brain operation performed for non-tumor related brain damage, the chances of survival are significantly enhanced.

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