transcrusal
superior & posterior semicircular canals are removed from the ampullae to the common crus
The transcrusal approach provides adequate exposure for most petroclival lesions and giant aneurysms of the upper basilar artery while offering the possibility of hearing preservation. Like all approaches to large tumors and aneurysms in this region, there is a significant risk of morbidity and mortality. However, this approach is an excellent alternative to other techniques that necessitate deliberate sacrifice of ipsilateral hearing 1).