Preoperative Cranial Nerve Deficits as Crucial Outcome Predictor for Skull Base Meningiomas

Objective: Meningiomas have various clinical presentations, and skull base meningioma harbors the most diversified symptoms of them. Many outcome-predicting factors for skull base meningiomas were profoundly discussed. However, we have yet to see a single predicting factor, which was easy to be evaluated preoperatively and was able to predict both functional and clinical outcomes. Our objective of this study was to examine the correlation between a single category of preoperative symptoms and outcomes of skull base meningiomas after multimodality treatments.

Material and Methods: The authors retrospectively reviewed the medical records and radiological data to obtain outcomes of patients who underwent treatments at our institute for their skull base meningiomas during 2010–2018. The analyses were designed to address the association among the preoperative cranial nerve deficits (CNDs), functional outcomes, and survival prognosis.

Results: A total of 143 patients were included with the median follow-up time of 27.3 months. Mostly mentioned chief complaints were eye symptoms (32.2%), unsteady gait (29%), headache (15.4%), and dizziness (7.7%). Eighty-one patients (56.6%) presented with preoperative CNDs, of which were smelling dysfunctions (CN1, 2.5%), eye symptoms (CN2–4, 54.8%), facial pain (CN5, 9.5%), facial palsy and tinnitus or hearing loss (CN7–8, 22.6%), and swallowing difficulties (CN9–12, 3.6%). The presentation of preoperative CNDs was associated with new onset or worsen postoperative CNDs (p < 0.001), tumor recurrence (p = 0.019), and requirements of adjuvant therapies (e.g., gamma knife surgeries or endoscopic endonasal surgeries, p = 0.006). The mean resection rate of patients with and without preoperative CNDs were 90 and 97%, respectively, (p < 0.0001). It may also correlate to a longer progression-free survival (p = 0.03), independent to the pathological grading (p = 0.25).

Conclusion: The presentation of preoperative CNDs may be considered as an outcome predictor for skull base meningiomas.