Cranial nerve function after cerebellopontine angle meningiomas removal

Abstract

Objective. To analyze cranial nerves (CN) dysfunction incidence in cerebellopontine angle (CPA) meningiomas removal depending on topographic and anatomical tumor location type and define the ways to reduce CN dysfunction incidence and severity. Materials and methods. The study included 30 CPA meningioma patients operated on in the clinic over a 10-year period (from 2010 to 2020 inclusive). Tumor characteristics, the degree of extent (including matrix location, particularly in relation to the internal auditory canal (IAC), jugular foramen (JF), and Meckel’s cave), and supratentorial extension were assessed. The tumors were divided into 5 groups according to the classification of Nakamura et al. Particular attention was paid to the presence and severity of pre- and postoperative cranial nerves dysfunction. Results. Different groups of CPA meningiomas in terms of the presence of a new CN neurological deficit were compared in the study. CN VII dysfunction was more frequently detected in group 2 — meningiomas extending to IAC, which was 54.5% of all observed tumors in this group vs. premeatal tumors, where new CN VII deficit was 20%, in group 1. At the same time in groups 3, 4, and 5 there was no new CN VII deficit. Conclusions. The most frequent symptoms in patients of all groups were dizziness, headache and unsteady gait. Of all the symptoms, only unsteady gait and hearing impairment were more common in patients in group 2, however the differences were statistically insignificant (p = 0.135 and p = 0.268, respectively). Trigeminal nerve and auditory nerve were most commonly affected. Auditory nerve lesions were more often detected in patients of group 2 than in patients of other groups, however, the differences were statistically insignificant (p = 0.268). In general, there were no statistically significant differences between the groups in terms of the incidence of various symptoms and the incidence of CPA cranial nerve damage.