SINCE the turn of the century surgeons have proposed many procedures for exposure of the hypophysis cerebri. Of the operations proposed, two principal routes have been selected to reach the hypophysis, first the intracranial and second, the extracranial or transsphenoidal.1-5 By whatever method the operation is performed, it is evident that one must have not only an accurate anatomical knowledge of the region involved but also an acquaintance with any marked variations from the usual type which might be encountered.
The hypophysis, or pituitary gland, is a small gland of dual origin. The adenohypophysis is derived from ectoderm of Rathke's pouch of the stomodeum. The neurohypophysis is derived from the neural ectoderm of the floor of the diencephalon.
The neurohyphysis consists of three parts: the median eminence of the tuber cinereum; the infundibular stem; and the infundibular process or pars nervosa or posterior lobe of the older terminology. The
Willson JT. Anatomical Considerations in Transsphenoidal Hypophysectomy. Arch Otolaryngol. 1967;86(3):245–251. doi:10.1001/archotol.1967.00760050247002