Direct Inspection with Dual Endoscope Technique via Bilateral Transforaminal Approach Leading to Complete Resection of Recurrent Colloid Cyst of the Third Ventricle

Background: Although endoscopic approaches are widely used for resection of colloid cysts because of the lower invasiveness, removal of the recurrent colloid cyst is still challenging. Total removal is sometimes difficult to achieve with single-port endoscopy because of the restricted access and working space. To compensate for these limitations, the dual endoscope technique via the bilateral transforaminal approach was chosen. Case Description: A 34-year-old woman with recurrent colloid cyst of the third ventricle was admitted to our department. She had a history of endoscopic subtotal removal at another institution. Reoperation was scheduled and the endoscopic bilateral transforaminal approach was chosen to ensure total removal with minimum complication risk. After decompression, the cyst was retracted toward the third ventricle floor via the right foramen of Monro. Under direct inspection with an angled scope via the right foramen of Monro, the cyst attachment on the third ventricle roof was sharply dissected via the left foramen of Monro, resulting in total removal. Conclusions: The dual endoscope technique via the bilateral transforaminal approach can achieve better surgical outcome by obtaining direct visualization of the cyst attachment. Although the indication should be limited, this approach can be considered especially for patients with recurrent lesions involving possible adhesion to vital structures.