There are six major hormone systems controlled directly or indirectly by the pituitary gland. Each pituitary axis work similarly to a thermostat system with a feedback loop. The pituitary gland sits in the sella turcica which is a bony structure behind the eyes. The pituitary is divided into two parts called the adenohypophysis which is the front portion and the back portion called the neurohypophysis. The important surrounding structures are the cavernous sinus located laterally on each side and superiorly the optic chiasm.