Increased serum prolactin (hPRL) and increased volume of the sella turcica as detected by roentgenography are compatible with a pituitary adenoma. The empty sella syndrome can increase sella volume, but is usually associated with minimal, if any, endocrine dysfunction. The present case details a young woman with amenorrhea, galactorrhea, elevated serum hPRL, and roentgenographic evidence of an enlarged sella turcica. Pneumoencephalography with hypocycloidal polytomography is interpreted as both an empty sella, and evidence of a pituitary adenoma. The etiology and endocrine findings in the empty sella syndrome are discussed.