Abstract Background Invasion of the CS is one of the limiting factors for total resection for PitNet tumors with cure rates less than 30%. Extended approaches may be considered in selective and well-studied cases of secreting adenomas. Method We describe the key steps of the endoscopic transcavernous approach for functional pituitary adenomas with a video illustration. The surgical anatomy is described along with the advantages and limitations of this approach. Conclusion A detailed knowledge of CS anatomy and familiarity with this surgical approach acquired in the laboratory is essential. Proper instrumentation is critical to decrease the risks of vascular injury.