Expanded Endoscopic Endonasal (EEN) Approach to Clival Tumors

Aim: To review our experience with the EEN approach for clival tumors.

Materials and Methods: Retrospective analysis of patients with clival lesions undergoing EEN procedures between 2008 and 2014 in CHUV. Cases were reviewed for diagnosis, treatment, complications and outcomes.

Results: 11 patients with clival tumors were included (7 females and 4 males; mean age of 45 years): 3 chordomas, 3 meningiomas, 3 metastatic diseases (2 rhinopharyngeal lympho-epithelial carcinoma and one melanoma), one chondrosarcoma and one chondroma.

3 patients had purely clival lesions and the approach was uniquely EEN (2 chordomas and one chondroma) with a complete resection at the 3-months cerebral MRI. One patient had a petroclival chordoma and one had metastatic melanoma extending to sphenoidal sinus and clivus: both patients had EEN approach with a residual disease treated by postoperative radiotherapy (the metastatic melanoma was also treated by gamma knife (GK)). The 3 patients with the meningioma had a petroclival extension (in 2 cases with involvement of sphenoidal sinus and cavernous sinus) and they had combined surgery with EEN plus craniotomy. The resection was subtotal and the residual disease in the cavernous sinus was treated by GK. The 3 last patients (metastatic diseases and chondorsarcoma) were operated with a transsphenoidal-transpterygoid approach: they had extensive lesions with a far lateral extension, the endoscopic resection was undertaken with a palliative intent and they underwent adjuvant therapy.

The mean follow up was 20 months: one patient developed hydrocephalus and meningitis after a lumbar drain. At the last follow up 10 patients were alive: 3 were free of disease, 6 had controlled residual disease and one progressed further. One patient died due to extensive progression of the disease.

Conclusions: Treatment of clival lesions is challenging¹ and the management has dramatically changed since the advancement of the EEN technique. EEN approach avoids cerebral retraction and decreases incidence of injury of lower cranial nerves, while yielding similar surgical results.^2,3 Postoperative CSF leakage was limited by the accurate reconstruction with the Haddad flap. The use of neuronavigation and dedicated endoscopic instrumentation makes the EEN approach advisable and even preferred to traditional approaches. The key to the success? A good knowledge of the endoscopic skull base anatomy and a multidisciplinary team.

References

References

1 Al-Mefty R, Dunn IF, Pravdenkova S, Abolfotoh M, Al-Mefty O. True petroclival meningiomas: results of surgical management. J Neurosurg 2014;120(1):40-51

2 Stippler M, Gardner PA, Snyderman CH, Carrau RL, Prevedello DM, Kassam AB. Endoscopic endonasal approach for clival chordomas. Neurosurgery 2009;64(2):268-278

3 Dehdashti AR, Karabatsou K, Ganna A, Witterick I, Gentili F. Expanded endoscopic endonasal approach for treatment of clival chordomas: early results in 12 patients. Neurosurgery 2008;63(2):299-309