Fig. 3.

Scheme depicting the extension and reach of transorbital endoscopic approaches (TO) with respect to transnasal endoscopic (TN) and most relevant open skull base approaches. A Anterior approaches (e.g., subfrontal); AL1, paramedian anterolateral approaches (e.g., supraorbital); AL2, anterolateral approaches (e.g., pterional, frontotemporal, orbito-zygomatic, frontotemporal-orbitozygomatic); L, lateral approaches (e.g., transpetrous, subtemporal middle cranial fossa, infratemporal); PL, posterolateral (e.g., trans-sigmoid, retrosigmoid); P1, paramedian posterolateral approaches (e.g., far lateral); P2, posterior approaches (e.g., suboccipital) [17]