The transsphenoidal route is mostly used and was the route first used by Harvey Cushing (Fig 3.18). Small, medium-sized and some large tumours, with suprasella extensions of up to 1cm, can be removed by this route. Removal of the latter can improve field defects, if present for a short period, once pressure on the optic chiasm is released. Cure by the transsphenoidal route is most often achieved with small tumours of under 1cm in diameter.
