A multimodal staged approach for the resection of a Sylvian aqueduct rosette-forming glioneuronal tumor: A case report and literature review

Background and importance: The rosette-forming glioneuronal tumor (RGNT) is a rare central nervous system tumor which often arises intraventricularly. We report the first surgical case of an RGNT arising from the Sylvian aqueduct treated through a double approach. Clinical presentation: A 25-year-old female presented with triventricular hydrocephalus on MRI secondary to a 2 cm Sylvian aqueduct mass. Emergent endoscopic third ventriculostomy with biopsy confirmed the diagnosis of RGNT. She was first followed up and due to the rapid tumor's growth a double surgical approach was proposed. The first was a telo-velar approach to the lower third of the aqueduct. The second stage was an endoscopic ultrasound aspirator aided transfrontal transforaminal approach; last postoperative MRI shows a 6 mm residual tumor. Patient leads an active working and social life. Conclusion: Choosing a two stages approach for this rare and complex Sylvian aqueduct RGNT resulted in a positive clinical and radiological outcome.