Table 1.

Classification of cochleovestibular schwannomas with location in the inner ear and the internal auditory canal. (After Kennedy et al. [21] and van Abel et al. [54])

Classification	Abbreviation	Cochlea	Vestibule ± SCC	IAC	Middle ear	CPA
Transmodiolara	TMOD	X	(X)	X	–	–
Transmacularb	TMAC	–	X	X	–	–
Translabyrinthinec	TLab	X	X	X	–	–
Transotic	TO	X	X	X	X	–
Involvement of the CPA	+ CPA	±	±	X	±	X

^aExtension through the modiolus into the internal auditory canal

^bExtension through the macula cribrosa into the internal auditory canal

^cExtension through the modiolus and the macula cribrosa into the internal auditory canal. For intravestibulocochlear tumors and location in the fundus of the IAC, the differentiation to transmacular and transmodiolar extension might be difficult. In our case series no tumor with certain transmodiolar and transmacular (i.e., translabyrinthine) extension was present. Also, this type of tumor extension is not part of the Kennedy et al. classification [21]

IAC internal auditory canal, CPA cerebellopontine angle, SSC semicircular canals