Resection of a craniopharyngioma using the "inside-out" technique: a two-dimensional operative video

A 57-year-old man presented with headache and obstructive hydrocephalus caused by a craniopharyngioma. He underwent gross-total resection through an endoscopic endonasal approach. The key surgical concept was the "inside-out" technique, in which the tumor was internally decompressed first, allowing the capsule to collapse and the dissection plane to be developed gradually from the center of the lesion toward its peripheral pial interface. This helped limit traction on the optic apparatus, hypothalamus, and perforating vessels. Multilayer reconstruction was performed and assessed using indocyanine green fluorescence endoscopy. This video highlights the technical nuances of the inside-out technique for maximal safe resection of craniopharyngiomas. The video can be found here: https://stream.cadmore.media/r10.3171/2026.7.FOCVID26115.