Endoscopic endonasal versus transcranial approaches for trigeminal schwannomas: choosing the optimal surgical corridor based on tumour traits.

BACKGROUND: Two primary surgical approaches, the transcranial approach (TCA) and the endoscopic endonasal approach (EEA), offer distinct advantages and disadvantages, but studies have yet to compare their outcomes for trigeminal schwannoma (TS) resection systematically. METHODOLOGY: A retrospective review of TSs between 2013 and 2023 was performed, with clinical characteristics, surgical outcomes, and follow-up data collected and analyzed. The patients were divided into two surgical groups, and tumours within each group were further classified according to the Samii system into middle fossa (type A), dumbbell-shaped involving middle and posterior fossae (type C), and extracranial with intracranial extension (type D), excluding posterior fossa (type B). RESULTS: A total of 101 patients (44 via EEA, 57 via TCA) were included. The two groups exhibited comparable baseline characteristics, except for the prevalence of dizziness in the pooled data (types A, C, and D). In pooled data and type A tumours, the EEA was associated with a statistically significant differences in higher gross total resection rate, shorter operative time, lower intracranial infection rate, and greater improvement in facial numbness. EEA was also significantly associated with a lower neurological deficits and higher Karnofsky Performance Scale scores in pooled data. Both approaches resulted in similar outcomes for type C tumours. EEA was advantageous for type D tumours in the infratemporal fossa, pterygopalatine fossa, and medial orbital regions, and no neurological deficits were observed. CONCLUSIONS: The optimal outcome of the surgical approach and minimization of morbidity for these complicated lesions depend on the meticulous selection of cases.