Endoscopic transventricular resection of a colloid cyst.

This video demonstrates the purely endoscopic gross-total resection of a third ventricle colloid cyst that is partially covered by a large thalamostriate vein. To gain an ideal approach, the initial trajectory pointed to the interventricular septum above the cyst. After the head of the caudate nucleus is passed, it is retracted laterally by the endoscopic sheath for the ideal far lateral approach to the cyst. Using a pneumatic endoscope holder enables the surgeon to perform the procedure bimanually. After complete removal of the cyst, postoperative inspection confirms the intact fornix, veins, and caudate nucleus without signs of pressure-related damage. The video can be found here: https://stream.cadmore.media/r10.3171/2023.1.FOCVID22140.