Pituitary tumors are tumors of the pituitary gland. These are almost always benign tumors that can cause hormonal disturbances in patients such as irregular periods, infertility or lactation. In addition, they can also cause visual problems by compressing the nerves that serve the eyes. When these tumors cannot be treated with medications alone, they are surgically removed. These tumors are usually removed via transsphenoidal surgery, an approach that goes through the nasal passage and back of the nose, across the sphenoid sinuses and into the skull base where the pituitary gland is located. Microscopes or endoscopes are used to visualize and remove the tumor. The tumor is generally surrounded by delicate and vital structures and great care must be taken not to compromise them.