How to Perform Transsphenoidal Approaches

Initial attempts at transcranial approaches to the pituitary gland in the late 1800s and early 1900s resulted in a mortality rate that was generally considered prohibitive. Schloffer suggested the use of a transsphenoidal route as a safer, alternative approach to the sella turcica. He reported the first successful removal of a pituitary tumor via the transsphenoidal approach in 1906. His procedure underwent a number of modifications by interested surgeons, the culmination of which was A. E. Halstead's description in 1910 of a sublabial gingival incision for the initial stage of exposure. From 1910 to 1925, Cushing, combining a number of suggestions made by previous authors, refined the transsphenoidal approach and used it to operate on 231 pituitary tumors, with a mortality rate of 5.6%. As he developed increasing expertise with transcranial surgery, however, Cushing reduced his mortality rate to 4.5%. With the transcranial approach, he was able to verify suprasellar tumors and achieve better decompression of the optic apparatus, resulting in better recovery of vision and a lower recurrence rate. As a result he and most other neurosurgeons at the time abandoned the transnasal in favor of the transcranial approaches. Norman Dott, a visiting scholar who studied with Cushing in 1923, returned to Edinburgh, Scotland, and continued to use the transsphenoidal procedure while others pursued transcranial approaches. Dott introduced the procedure to Gerard Guiot, who published excellent results with the transsphenoidal approach and revived the interest of many physicians throughout Europe in the early 1960s. Jules Hardy, who used intraoperative fluoroscopy while learning the transsphenoidal approach from Guiot, then introduced the operating microscope to further refine the procedure; he thereby significantly improved its efficacy and decreased surgical morbidity. With the development of antibiotic drugs and modern microinstrumentation, the transsphenoidal approach became the preferred route for the removal of lesions that were confined to the sella turcica. The evolution of the transsphenoidal approaches and their current applications and modifications are discussed.

As an element of a minimally invasive management approach, we had developed an endonasal endoscopic transsphenoidal technique for the treatment of pituitary tumors. Initially, four patients were operated on via a sublabial, transseptal approach using a fiberoptic rigid endoscope in conjunction with the operating microscope. Encouraged by that experience, our subsequent 11 patients had undergone endonasal endoscopic transsphenoidal surgery without the use of a retractor or speculum. Our group of patients included nine females and six males, with an age range of 17-88 years (median: 43 years). There were four microadenomas, four intrasellar macroadenomas, three macroadenomas with suprasellar extension, three invasive macroadenomas involving the cavernous sinus with suprasellar extension, and one metastatic adenocarcinoma. Thirteen patients with pituitary adenomas experienced resolution of their symptoms postoperatively. One patient with a recurrent prolactinoma responded partially following surgery and subsequently underwent gamma knife radiosurgery. Two patients were treated with postoperative fractionated radiation therapy, one for residual pituitary adenoma in the cavernous sinus, and the other for metastatic adenocarcinoma, respectively. The first patient, treated via an endonasal endoscopic approach for biopsy of the metastatic adenocarcinoma, developed postoperative cerebrospinal fluid (CSF) leak that was successfully managed with endoscopic packing of a fat graft. The endonasal endoscopic transsphenoidal approach facilitates faster postoperative recovery by the avoidance of traditional incision and postoperative nasal packing. It offers a panoramic view of the sphenoid sinus and excellent visualization of the sellar and suprasellar structures with increased illumination and magnification. Such visualization provides the potential for more complete tumor resection, as well as a better chance of preserving pituitary function and avoiding neurovascular injury.