Table 1 Castelnuovo grading system (type 1–3) for endonasal endoscopic nasopharyngectomy

Type 1

Starts with the removal of the posterior portion of the nasal septum. The resection is limited to the postero-superior nasopharyngeal wall, reaching the bony floor of the sphenoid sinus superiorly and the pharyngobasilar/prevertebral fascia posteriorly

Type 2

Extends superiorly to include also the anterior wall and the floor of the sphenoid sinus. In this case, the sphenoid rostrum and the intersphenoidal septum are removed

Type 3

Extends laterally to include the lateral nasopharyngeal wall and the cartilaginous portion of the eustachian tube