Although pituitary tumors were well recognized by the end of the 20th century, very few surgeons had attempted to remove such tumors. In 1906, Hermann Schloffer at the Innsbruck University Clinic of Surgery reviewed the subject of pituitary surgery. Very little was known about the function of the pituitary, and no reports had yet been published on attempts to surgically remove pituitary neoplasms. Schloffer pointed out that ophthalmological symptoms evidently reflected mass effect of the tumor and, hence, resection of the tumor would be beneficial. He also proposed a transsphenoidal approach to the sella, although he was well aware of the risk of meningitis associated with this procedure. On March 16, 1907, Schloffer performed the first transsphenoidal operation for a pituitary adenoma. Unfortunately, the patient died 2 months later from a large residual tumor. Within a few years, several patients had undergone operation with procedures similar to the one described by Schloffer, several of whom experienced acromegaly, thus introducing neurosurgery as routine therapy for acromegaly and settling the long debate on the etiology of acromegaly.