Asymptomatic Intracochlear Neurinoma: A Temporal Bone Report

Primary tumours of the vestible and inner ear

“…Hallpike (1963) described a case of conductive deafness in a patient with NF-2 and at post-mortem a 'seedling' tumour was found in the vestibule impeding the movement of the stapes. A similar appearance was described by Johnsson and Kingsley (1981) of a 1.5 mm tumour arising in the scala tympani and seeming to originate in the distal cochlear neurone. Gussen (1971) recorded an interesting post-mortem study of a 57-year-old man, not suffering from NF-2, who had a 24-year history of deafness in his left ear, with tinnitus and dizzy spells which sound typical of Meniere's disease, lasting for three to seven hours, accompanied by vomiting and occurring about once per week.…”

“…Although the majority of intracranial vestibular schwannomas arise on one or other branch of the vestibular nerve, it has been suggested that there is a greater tendency for primary intravestibular tumours to originate from the cochlear division (Huang, 1986), although the number of cases in which there is unequivocal evidence of the site of origin is too small to allow one to draw any definite conclusions as to site of origin. The cases described by Gussen (1971), Hoshino and Ishii (1972), Jorgensen (1962), Johnsson and Kingsley (1981) all arose on the cochlear nerve. The cases of Weymuller (1975), Stewart et al (1975) and Vernick et al (1984) arose on the superior vestibular nerve.…”

Diagnosis and Management of Intracochlear Schwannomas

“…In our patients and in the literature, the hearing loss is the major symptom (1). The hearing loss might be absent or moderate in the initial phase of tumor development as noticed in 2 of our patients and in other reported cases (9,19). The SNHL is frequently progressive, but sudden SNHL is described in 15% of the cases (1).…”

Cochlear Schwannomas

“…Postmortem cases of an intracochlear or intracanalicular neuroma (one case in our study) or both have been described 10,11,12 in patients who had no hearing problems while alive. Our patient noted an abrupt but reversible hypoacusia and incapacitating tinnitus followed by a new and sudden irreversible hearing loss that resolved into profound deafness 6 months later.…”

“…5 Tinnitus occurred in five of our patients; Leonetti 5 reported that only two of 16 patients with cochlear schwannoma had tinnitus. In their study of postmortem cases, Ayani 10 and Johnsson 11 reported no tinnitus in previous anamnestic data. Some authors 1,2,8,9 have correlated the presence of a vertigo syndrome to the evolution of cochlear neuromas.…”