Objective: Giant pediatric midline tumors of the posterior fossa involving the fourth ventricle and the tectal region are difficult to approach and present a high risk of postoperative neurological deficits. Children with sequelae such as cerebellar mutism and ataxia experience a compromise in their quality of life. Here, we present our combined transventricular and supracerebellar infratentorial approach to avoid complications of vermian splitting.
Methods: The combined transventricular and supracerebellar infratentorial approach described here was used in a total of four pediatric patients. A medial suboccipital craniotomy with opening of the foramen magnum and resection of the C1 lamina was performed with the patient in the semisitting position. The tumor mass filling the fourth ventricle was removed via a transventricular telovelar route through the foramen of Magendie, preserving the vermis. The rostral tumor portions in the peritectal region extruding up to the thalami were exposed and resected via an infratentorial supracerebellar route to preserve the venous drainage of the cerebellum.
Results: There were no new neurological deficits postoperatively. Two patients had low-grade astrocytomas, and two patients had malignant tumors. Complete tumor resection was achieved in two patients, and near-total tumor removal in the two others.
Conclusion: The combined transventricular and supracerebellar infratentorial approach offers a unique possibility of safely removing giant pediatric midline tumors. Splitting of the cerebellar vermis is not necessary for removal of such tumors.