The sublabial transseptal transsphenoidal approach to the hypophysis.

A simple and safe technique for the sublabial transseptal transsphenoidal approach to the hypophysis and parasellar region is described. A review of the literature reveals that this technique and other transsphenoidal routes to the hypophysis were performed more than half a century ago.These procedures fell into disfavor because fo low magnification and insufficient illumination of the operative field, infection and inadequate postoperative endocrine replacement therapy. With today's antibiotic therapy and hormonal replacement, plus the use of the operating microscope, the transsphenoidal route to the hypophysis has gained renewed interest among neurosurgeons and otolaryngologists. Each of the transsphenoidal routes and the advantages of the "from below" approach are described. The applications of transsphenoidal approach and the nonsurgical modalities for hypophysectomy are reviewed. The simplicity and safety of the sublabial transseptal transsphenoidal approach depend on a thorough familiarity with the surgical anatomy, proper positioning of the patient, and the availability of appropriate instrumentation. Photographs of specially prepared whole head anatomical specimens plus skull dissections with radiographic correlation illustrate the pertinent anatomy. Some of the vital structures to be identified and avoided are the optic canals, carotid arteries, circular sinuses, cavernous sinuses, III, IV, V, VI cranial nerves, foramen rotundum, medial walls of the orbits, medial walls of maxillary sinuses, medial pterygoid plates and pterygoid canals. A method for preoperative determination of key distances within the patient's skull is described along with other preoperative tests. This paper discusses the self-retaining speculum and other new instruments for this procedure. A gauge mounted on the front end of the speculum is calibrated to measure the size of the opening at the tip of the speculum. Thirty cases are included in this report, six of which are presented in detail. No operative mortality, CSF rhinorrhea, visual damage carotid or cavernous sinus hemorrhage fracture of the medial pterygoid plates or maxilla were encountered in this series. Three patients developed diabetes insipidus and two patients had meningitis which responded to antibiotic therapy.