Combined Endoscopic and Microsurgical Interhemispheric Transcallosal Approach: A Minimally Invasive Strategy to Manage Complex Third Ventricular Lesions

Introduction: Surgical approaches to deep-seated brain pathologies, specifically lesions of the third ventricle, have always been a challenge for neurosurgeons. The endoscopic resection of intraventricular lesions has gained increasing popularity in recent years. However large, vascular, or extremely firm lesions are better approached microsurgically. In these cases, the transcallosal approach remains the most suitable option, to not violate the brain parenchyma, even if it carries a risk of postoperative cognitive and memory deficits in the event of bilateral fornical injury. In this background, the combined use of the endoscopic and microsurgical technique that requires a minimal callosotomy to reach the ventricular compartment, could combine the advantages of both techniques, then increasing the likelihood of a safe and complete resection.

Materials and Methods: The authors present four cases of complex third ventricular lesions treated via the combined endoscopic and microsurgical transcallosal approach. The first two patients presented with a solid-calcified colloid cyst of the third ventricle, while the second two patient had a large anaplastic ependymoma that originated in the third ventricle and extended to both frontal horns and atrium of the lateral ventricles and a giant cells subependymoma.

Results: Gross total removal was achieved in all patients, beside one subtotal. No post-operative major complications occurred, two had transient mutism and spatia. Radiological follow-up at 1 years no showed recurrence of the lesions. All two patients had good neurological outcomes.

Conclusion: The combined endoscopic and microsurgical transcallosal approach could represent an effective and safe alternative to treat complex third ventricular lesions. The probable advantages of this approach are more complete resection (guaranteed by the microsurgical technique) and improved safety related to a less manipulation of corpus callosum and fornices (thanks to endoscopic technique).