Endoscope-assisted craniotomy: approach to the rostral brain stem.

We describe a surgical technique to improve visualization of deep brain structures during craniotomy. The technique, developed in a cadaveric model, combines the use of an operating microscope and a solid-rod lens endoscope. Addition of the endoscope during craniotomy allows the operator to visualize structures that otherwise might not have been seen. An approach to the brain stem is demonstrated.