Pituitary gland (Hypophysis cerebri) is a reddish gray ovoid body, composed of 2 lobes. Adenopophysis which is responsible for secretion of the pituitary hormones, and the neurohypophysis which contain Axons and Axon terminals from the hypothalamus it regulates the function of adenohypophysis. At least seven hormones are synthesized and released from adenohypophysis ACTH, GH, prolactin FSH, LH, TSH and MSH. Neurohypophysis synthesize and release 2 hormones oxytocin, vasopressin H (ADH). Pituitary adenomas contributes 10-15 of All Intracranial Tumors, they are usually benign slowly growing small neoplasms. They are classified into pituitary microadenomas (less than 1 cm in size), and pituitary macroadenomas (more than 1 cm in size). Pituitary microadenomas are either secreting or non-secreting, secreting microadenomas causing either hyperprolactinemia, acromegaly, Cushing syndrome or hyperthyroidism. There are different endocrine testing used for evaluation of patients with pituitary microadenomas pituitary microadenomas are best seen by MRI, to less extent by CT. Pituitary microadenomas are treated either conservatively, medically, surgical through trans-sphenoid approach (microscopic or endoscopic) or by radiotherapy (including Gamma knife).