Endoscopic extracapsular dissection for resection of pituitary macroadenomas: technical note.

OBJECTIVE: With the increasing use of the endoscope in neurosurgery, transsphenoidal surgery has undergone a considerable technical evolution. However, most recently reported advances relate to the approach to the sella turcica or to extended transsphenoidal approaches, whereas the dissection technique for pituitary tumor removal itself has received more limited attention. A notable exception is Oldfield's elegant description of an extracapsular dissection of functional pituitary microadenomas. Our objective is to describe and illustrate our technique for endoscopic extracapsular resection of pituitary macroadenomas.

METHODS: Influenced by Oldfield's description, we have adopted an extracapsular dissection technique in the endoscopic resection of pituitary macroadenomas. After carefully opening the dura without disrupting the macroadenoma pseudocapsule, the pseudocapsule is dissected inferiorly and laterally. The tumor is then internally debulked and the extracapsular dissection is extended circumferentially; the resection is then complete.

RESULTS: The enhanced visualization and illumination afforded by the endoscope enables the identification and surgical dissection of the pseudocapsule at the periphery of the macroadenomas under direct vision in most cases. As demonstrated in the illustrative case, working around the macroadenoma pseudocapsule allows for a definitive and complete macroadenoma resection with direct visual confirmation and with preservation of the normal gland and diaphragma.

CONCLUSION: The endoscopic transsphenoidal approach permits an extracapsular dissection of many pituitary macroadenomas. In our preliminary experience, this technique appears to result in a high rate of complete resection without an increase in complications.