Comparative analysis of facial nerve outcomes in petroclival versus posterior petrous meningioma surgery: A systematic review and meta-analysis of 2884 patients.

BACKGROUND

Even conservative resection of petroclival (PC) and posterior petrous (PP) meningiomas may cause facial nerve (FN) morbidities. While inconsistent classifications by tumor's dural origin circulate among different cohorts, a comprehensive assessment of postoperative FN outcomes is lacking. We systematically evaluate early and long-term FN outcomes related to surgical extirpation of PC and PP meningiomas.

METHODS

A PRISMA-tailored survey of PubMed, Embase, Ovid/Medline, and Scopus was used to assess pooled perioperative FN deficit rates in PC and PP meningiomas. Outcomes were dichotomized by tumor's dural origin (PC vs. PP group), age (≥50 vs. < 50 years), and tumor size (≥ 3.5 vs. < 3.5 cm), and analyzed using random-effect meta-analysis.

RESULTS

Forty-one studies involving 2884 patients with an average tumor size of 3.5 cm met the eligibility criteria. Pooled gross total resection rates were 48 % for PC and 69.6 % for PP groups. FN deficits rates (HB grade > II) at presentation, early postoperative (new-onset during admission), and long-term (≥6-month follow-up) were respectively 12 % (CI:7.7-16.3 %; p < 0.001; I2 = 89.7 %), 18.6 % (CI:14-23.2 %; p < 0.001; I2 = 89.9 %), and 8.3 % (CI:5-11.7 %; p < 0.001; I2 = 87.3 %) in "PC group", and 6.4 % (CI 3.8-9 %; p < 0.001; I2 = 79.4 %), 16.2 % (CI:10.3-22.2 %; p < 0.001; I2 = 89.4 %), and 9.2 % (CI:3.9-14.5 %; p < 0.001; I2 = 91.2 %) in "PP group." The mixed-effect model revealed significantly higher FN deficit rates at presentation for larger PP meningiomas (15.9 % in size ≥ 3.5 cm vs. 5.8 % for < 3.5 cm, p = 0.003), while larger PC meningiomas had higher early postoperative rates (18.1 % vs. 3.9 %, respectively, p < 0.001). Tumor size, age, or dural origin did not impact overall long-term outcomes.

CONCLUSIONS

No significant difference was observed in long-term FN outcomes between PC and PP meningiomas. Anatomic preservation of the nerve should be prioritized regardless of tumor size, approach, or dural origin, as many deficits improve in the long-term. Although challenging, in meningiomas ≥ 3.5 cm, preoperative detailing of the dural origin is of value in patient consultation, as larger sizes worsen "early" FN outcomes only in true PC meningiomas.