Unusual approaches for pituitary adenomas.

For pituitary adenomas surgery, rhinoseptal transsphenoidal approach is use d in 98 to 99 % of the cases. Although this approach is fitting for microad enomas and the majority of macroadenomas, some of them develop extensions i n the nasal fossas, the posterior cranial fossa, the suprasellar region, or into the cavernous sinus and will require other approaches. For the superi or routes, the frontopterional approach gives good control of the suprasell ar region, the anterior and middle base of the skull. The tumor dissection is performed inside the concavity of the chiasm and between the internal ca rotid artery and the optic nerve (optico-carotid approach). The frontopteri onal approach is used for superolateral extensions, especially in the later al fissure. The bifrontal basal inter hemispheric approach, through a media l frontal bone flap tangential to the base, gives a good route to the supra sellar region and behind the dorsum, and also for tumors extended in the th ird ventricle in case of prefixed chiasm. For the inferior routes, the part icipation of ENT or craniofacial surgeons is a great help. The transfacial of transethmoidal approach performs a hollowing of the nasal fossas and giv es a large interorbital tunnel adapted for tumors extended in the rhinophar ynx and the ethmoid. The Le Fort I maxillary osteotomy offers also a large approach for adenomas extending in the rhinopharynx. The transcavernous app roach from Dolenc, for adenomas progressing in the cavernous sinus requires a long and difficult procedure. The progression of some adenomas in many d irections may require a combined approach in one or two procedures.