”Tailored” far lateral approach to anterior foramen magnum meningiomas – The importance of condylar preservation

Abstract

Introduction: Anterior and anterolaterally situated foramen magnum meningiomas are a technically complex subgroup of meningiomas. The need for an extensive exposure and bone work and their complex anatomy make them a difficult and challenging group of tumors to resect. The bone work has ranged from an extensive condylar resection to condylar preserving exposures. In this paper, we present our experience with condylar preserving or minimal condylar resection based approaches to these tumors. Materials and Methods: All patients who underwent surgical resection of anterior and anterolaterally situated foramen magnum meningiomas were included in the analysis. The study period was more than 10 years from 2005 to 2015 at our institute; a tertiary referral centre in India. The records along with demographic profile, clinico-radiological features, surgical strategies, outcomes as well as mortality and morbidity were analysed. Results: There were a total of 20 patients (9 males and 11 females) who were operated during the study period. The average age was 36.7 years. In 16 patients, gross-total or near-total resection could be achieved, four patients underwent subtotal resection. Eight patients had fresh morbidity in the form of new motor deficits, pseudomeningocele formation, worsening of the lower cranial nerve functions or post-operative adhesions leading to syrinx formation. The follow-up ranged from 6 months to 140 months. Conclusion: Foramen magnum meningiomas are an eminently treatable group of tumors. Condylar preservation provides a good visualization, while helping to preserve joint stability and in avoiding instrumental stabilization.