Haen provided the first description of amenorrhea in connection with a pituitary tumor. He recorded the case history of a young woman suffering from amenorrhea as well as many neurological symptoms assumed to result from increased intracranial pressure, and a tumor in the area of the optic chiasma and the pituitary gland. Autopsy revealed a tumor in that location, and the tumor was correctly assumed to be the cause of the patient's illness and death. Digital facsimile from the Internet Archive at this link.