Endoscopic Endonasal versus Transcranial Approach to Tuberculum Sella and Planum Meningiomas in a Similar Cohort of Patients

Introduction: Planum sphenoidale (PS) and tuberculum sella (TS) meningiomas cause visual symptoms from compression of the optic chiasm. The treatment of choice is surgical removal with the goal of improving vision and achieving complete tumor removal. Two options exist to remove these tumors, either the transcranial approach (TCA) or the endonasal endoscopic approach (EEA). Significant controversy exists regarding which approach provides the best results and if there is a subset of patients for which the EEA approach may be more suitable. Comparisons using a similar cohort of patients, namely those suitable for gross total resection with EEA, are lacking from the literature.

Methods: We reviewed all cases of PS/TS meningiomas removed surgically at Weill Cornell Medical College between 2000–2015 (TCA) and 2008–2015 (EEA). All cases were shown to a panel of three neurosurgeons to find only those cases that could be removed equally well either through an EEA or TCA to standardize both groups. Volumetric measurements of pre-operative and post-operative tumor size, FLAIR and ADC maps were assessed by two independent reviewers and compared with assess extent of resection and trauma to the surrounding brain. Visual outcome and complications were also compared.

Results: Thirty-two patients were identified that underwent either EEA (n = 17) or TCA (n = 15). Pre-operative tumor size was comparable (5.58 ± 3.42 versus 5.04 ± 3.38 cm3, p = 0.661). The average extent of resection achieved was not significantly different between the two groups (98.80%±3.32 versus 95.13%±11.69, p = 0.206). Post-operatively, the TCA group demonstrated a significant increase in the FLAIR/edema signal compared with EEA patients (4.15 ± 7.10 versus -0.69 ± 2.73 cm3, p = 0.012). In addition, post-operative DWI signal of cytotoxic ischemic damage was significantly higher in the TCA group compared with the EEA patients (1.88 ± 1.96 versus 0.40 ± 0.55 cm3, p = 0.008). Overall, significantly more EEA patients experienced improved or stable visual outcomes compared with TCA patients (93% versus 56%, p = 0.047). Visual deterioration was higher after TCA than EEA (44% versus 0%, p = 0.012). While more patients experienced post-operative seizures after TCA compared with EEA (27% vs 0%, p = 0.038), there was a trend toward more CSF leak and anosmia after EEA compared with TCA (11% versus 0%, p = 0.486 and 11.8% versus 0%, p = 0.118, respectively).

Conclusions: In this small single institution study of similarly sized and placed PS and TS meningiomas, EEA provided equivalent rates of resection with better visual results, less trauma to the brain and fewer seizures. These preliminary results merit further investigation in a larger multi-institutional study and may support EEA resection by experienced surgeons in a subset of carefully selected PS and TS meningiomas.