Pituitary adenoma history and symptoms

Overview
Pituitary adenomas are tumors that occur in the pituitary gland, and account for about 10% of intracranial neoplasms. They often remain undiagnosed, and small pituitary tumors are found in 6 to 24 percent of adults at autopsy. Pituitary adenomas arise within the anterior lobe (adenohypophysis) of the gland. Tumors less than 1 cm are called micro adenomas. Clinical symptoms depend on whether the tumor is secreting or nonsecreting. Nonsecreting adenomas grow and compress adjacent structures, most commonly causing a bitemporal hemianopsia due to chiasmatic compression. Lateral extension into the cavernous sinuses can result in cranial nerve palsies.

History and symptoms
The diagnosis is generally entertained either on the basis of visual difficulties arising from the compression of the optic nerve by the tumor, or on the basis of manifestations of excess hormone secretion: the specifics depend on the type of hormone. The specific area of the visual pathway at which compression by these tumours occurs is at the optic chiasma.