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Extended endoscopic endonasal approach to the skull base.

OBJECTIVE
Different approaches to the skull base have been developed through the sphenoidal sinus. Traditional boundaries of the trans-sphenoidal approach can be extended in antero-posterior and lateral planes. We review our experience with the extended endoscopic endonasal approach in the first 12 cases.


METHODS
We used the extended endoscopic endonasal approach in 12 patients with different lesions of the skull base. This study specifically focuses on the type of lesions, surgical approach, outcome and surgical complications.


RESULTS
The extended endoscopic endonasal approach was used in 12 patients with the following lesions: 4 invasive adenomas to the cavernous sinus, 2 clival chordomas, 2 craniopharyngiomas, 1 hypothalamic astrocytoma and 3 pituitary adenomas extended upon the tuberculum. Gross total resection was achieved in 8 cases (66.7%) subtotal resection in 3 and just a biopsy could be accomplished in the case of astrocytoma. This last patient developed meningo-encephalitis and died two weeks later.


CONCLUSIONS
The extended endoscopic endonasal approach is a promising minimally invasive alternative for selected cases with sellar, parasellar or clivus lesions. As techniques and technology advance, this approach may become the procedure of choice for most lesions and should be considered an option in the management of the patients with these complex pathologies by skull base surgeons.