Evolution of the endoscope and endoscopic sinus surgery.

Advances in instrumentation are part of the natural evolution of any surgical discipline. During this process, there are certain key junctures where the state of the art in technology truly augments the surgeon's ability to manage higher levels of pathology. The present era of endoscopic sinus surgery has been hallmarked by extension of minimally invasive techniques to complex pathologies including advanced inflammatory disease, and pathology involving the orbit, skull base, and brain. Evolution of the armamentarium for endoscopic visualization has been a central feature in this. In this article, key historical elements are reviewed and the technical principles behind these important advances in endoscopic visualization are discussed.