CC BY-NC-ND 4.0 · J Neurol Surg B 2019; 80(S 03): S311
DOI: 10.1055/s-0039-1677858
Skull Base: Operative Videos
Georg Thieme Verlag KG Stuttgart · New York

Retrosigmoid Transmeatal Approach with 360-Degree Drilling of the Internal Auditory Canal for the Resection of Intracanalicular Meningioma

Ricardo Ramina
1  Department of Neurosurgery, Neurological Institute of Curitiba, Curitiba, Brazil
,
Felipe Constanzo
1  Department of Neurosurgery, Neurological Institute of Curitiba, Curitiba, Brazil
,
Erasmo Barros da Silva Jr
1  Department of Neurosurgery, Neurological Institute of Curitiba, Curitiba, Brazil
,
Maurício Coelho Neto
1  Department of Neurosurgery, Neurological Institute of Curitiba, Curitiba, Brazil
› Author Affiliations
Further Information

Publication History

30 May 2018

11 November 2018

Publication Date:
07 March 2019 (online)

  

Abstract

Introduction Vestibular schwannomas are the most common lesions occupying the internal auditory canal (IAC); however, almost in 4 to 5% of meningiomas, metastases, cysts, lipomas, and cavernous malformations have been found in this location, mimicking schwannomas. Even though cerebellopontine angle (CPA) meningiomas with the involvement of the IAC are frequently encountered, the presence of a primary intracanalicular meningioma is rare.

Objective To show the technical nuances of the retrosigmoid-transmeatal approach to successfully achieve gross total resection (GTR) with preservation of facial and auditory function.

Case Report We present a left intracanalicular meningioma on a 60-year-old man with history of tinnitus and hearing loss. Magnetic resonance imaging (MRI) showed a left intracanalicular lesion completely obliterating the IAC and with minor extension to the CPA cistern, with the vestibulocochlear complex dislocated posteriorly, initially diagnosed as a Hannover's T2 vestibular schwannoma. The patient underwent a left retrosigmoid approach, and during the exposure of the lesion, the diagnosis of a meningioma became evident. The transmeatal phase of the approach was modified with a wide opening of the canal, including the anterior wall. Closure was performed using a muscle graft, duramater flap, and fibrin glue.

Results GTR was achieved and the patient developed a mild facial palsy (House–Brackmann grade III) which completely recovered within 3 months.

Conclusions The retrosigmoid transmeatal approach is suitable to achieve GTR in intracanalicular meningiomas. Some modifications of the approach intended for vestibular schwannomas are necessary and may be performed during the procedure.

The link to the video can be found at: https://youtu.be/A9OXRFIl1e8.