Alterations in the flow of blood within the brain (hemorrhages), changes in the cerebrospinal fluid (infections) and brain tissue (cancer, swelling) are conditions under which surgeons need to consider neurosurgery. The various types of brain cancer that require craniotomy are as follows: gliomas, lymphomas, pituitary tumor, medulloblastoma, schwannoma, secondary tumor, chordomas etc. Head injuries such as concussions, scalp wounds, contusions, hemorrhages or fracture of the skull due to accidents also require brain surgery. Strokes can lead to potentially fatal brain injury and the same is true when the blood flow increases, which can lead to the rupture of small vessels in the brain.
But not every side effect is a bad one. Some are downright welcome. Take finasteride . Introduced in 1992 to treat noncancerous enlargement of the prostate gland , it was found to regrow hair (and is marketed for that purpose under the name Propecia). Today, millions of men use a low dose of finasteride to treat male pattern baldness . Similarly, minoxidil , originally marketed as an oral tablet for high blood pressure , was found to grow hair in those using it. Today, as a topical lotion or foam, it is a popular over-the-counter remedy for baldness.