Is endoscopic inspection necessary to detect residual disease in acoustic neuroma surgery?

MAIN GOALS: To analyze how and when the endoscope is used in vestibular schwannoma surgery and identify the benefits of using endoscopy in this type of surgery. BACKGROUND: It is currently unclear if there is any benefit from using an endoscope in vestibular schwannoma surgery so this retrospective analysis set out to study this. METHODS: All the patients who underwent vestibular schwannoma surgery at our clinic were included for all the vestibular schwannoma approaches taken. We studied when endoscopy was used during surgery and the goal of using endoscopy. Several pre- and postoperative factors were assessed such as complications, facial function, and hearing function in the case of techniques that allow hearing preservation. RESULTS: From January 2015 to September 2018, 280 patients underwent lateral skull base surgery. Of these, 112 were included in this study. The endoscope was used in all 112 patients, and in eight cases it was possible to identify residual disease using the endoscope to check the surgical field, and then to remove the disease under endoscopic view. Moreover, in two other cases, the endoscope was used to resolve a vasculoneural conflict between the anterior inferior cerebellar artery (AICA) loop and facial nerve in one case, and for deafferentation of the superior and inferior vestibular nerves in the second case. No major intraoperative complications occurred in our series. There was no statistically significant difference in postoperative facial nerve function between patients in whom the endoscope was used as a diagnostic tool and patients in whom it was used as an operative tool (p = 0.3152). CONCLUSIONS: The endoscope may be useful, especially in surgical techniques where there is poor control of the internal auditory canal (IAC). An endoscopic support technique is strongly recommended to avoid residual disease, particularly in retrosigmoid and retrolabyrinthine approaches. Moreover, the recent introduction of the transcanal transpromontorial approach allows the endoscope to be used during all the procedures in patients affected by a vestibular schwannoma limited to the IAC or to support surgical procedures during an enlarged microscopic approach.

Intratumoral Bleeding in a Vestibular Schwannoma

Vestibular schwannomas (VSs) account for 70% of all tumors of the cerebellopontine angle (CPA). Their clinical presentation is often insidious, with progressive hearing loss and involvement of other cranial nerves. Spontaneous hemorrhage in those tumors is very unusual, and generally presents with acute clinical features such as nausea, vomiting, headache and altered consciousness, usually with marked dysfunction of the cranial nerve involved, and with new deficits of neighboring cranial nerves. Asymptomatic patients are extremely rare. We present a case report of an incidental VS with asymptomatic bleeding, which evolved to death after surgery.

Schwannomas vestibulares (SVs) são responsáveis por cerca de 70% de todos os tumores do ângulo pontocerebelar. Sua apresentação costuma ser insidiosa, com perda auditiva progressiva e envolvimento de outros nervos cranianos. Hemorragia espontânea nesses tumores é incomum, e geralmente apresenta-se agudamente, com náusea, vômitos, cefaleia e alterações de consciência, normalmente com disfunção importante dos nervos cranianos envolvidos e com novos déficits dos nervos próximos. Pacientes assintomáticos são extremamente raros. Apresentamos um relato de caso de um SV incidental com sangramento assintomático que evoluiu para o óbito após cirurgia.