Removal of Koos IV acoustic neuroma and auditory brainstem implant in NF2 patient.

Maria Rosaria Scala,Serena Dé Santi,Antonio Della Volpe,Alfonso Maria Varricchio,Stefania Picariello,Giuseppe Cinalli,Claudia Santoro,Pietro Spennato,Claudio Ruggiero

doi:10.3171/2021.7.focvid2188

Abstract

The authors present the case of removal of a Koos grade IV right acoustic neuroma in a neurofibromatosis type 2 (NF2) patient, already operated on for left cerebellopontine angle meningioma at 7 years of age and a left acoustic neuroma at 16 years of age. A transpetrosal approach allowed cochlear sensor implantation to detect residual hearing. An enlarged retrosigmoid approach then allowed subtotal microsurgical removal of the lesion; consequently, the authors illustrate the technical nuances of an auditory brainstem implant (ABI). One month after surgery, the ABI was successfully switched on, giving back hearing perception to the patient.The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID2188

Highlights

In this video we will present the removal of a Koos grade IV acoustic neuroma followed by auditory brainstem implant in an neurofibromatosis type 2 (NF2) patient
This 16-year-old girl affected by NF2 had already been operated in our department of complete removal of a left CP angle transitional meningioma
In the upper part of the tumor volume, we are trying to identify the facial nerve in order to protect it during the further phases of the dissection, and here we can see the facial nerve and we can isolate it and continue with the debulking and removal of the tumor safely without risk to damage the facial nerve during these phases. This phase of identification is mandatory in order to try to save the facial nerve, in such a large tumor and especially in an NF2 patient it is always very difficult to protect and respect the facial nerve that, as you can see, is extremely squeezed by tumor compression, but we try to keep the integrity of the facial nerve throughout the surgery, dissecting it slowly from the outer capsule of the acoustic neuroma

Summary

Introduction

In this video we will present the removal of a Koos grade IV acoustic neuroma followed by auditory brainstem implant in an NF2 patient. Right retrosigmoid approach for tumor removal and auditory brainstem implant was decided.

Results

Conclusion