|MadSci Network: Neuroscience|
> If a brain tumor has grown over an optical nerve, why cant it be removed?I cannot answer your question from here. The answer depends on where in the optic nerve the tumor, the type of tumor, how far, if at all, the tumor has spread and wether any other treatments, such as chemotherapy or radiation are available. These are questions that the patient and his/her family have to take up with the doctors taking care of the patient.
If it could be removed at the expense of the optical nerve, why couldn't the optical nerve be attached without losing sight?The optic nerve is part of the brain. Once nerve fibers in the brain are cut, they are unable to grow back. Scientists are studying this very question. Part of the answer has to do with the cells that surround the nerve fibers or axons in the optic nerve do not let the nerve fibers grow back. In the future, it might be possible that the sight could be restored after the optic nerve is cut, but for now it is not.
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