Surgical anatomy and embryology of the frontal sinus

Abstract

As with any surgical procedure, a thorough knowledge of anatomy is the one most important factors in minimizing complications and maximizing one's chances of a good surgical outcome. This is particularly important for otolaryngologists performing endoscopic sinus surgery, as each and every one of the paranasal sinuses are in close proximity to critical orbital and skull base structures. A good knowledge of anatomy will enable the surgeon to operate with more confidence, by improving one's ability to correctly interpret normal variants from abnormal or pathological conditions, and determine an appropriate surgical treatment plan to reestablish mucociliary flow to the sinus. This is even more critical for distorted anatomy, due to previous surgery or neoplasms. Furthermore, CT imaging has become an integral part of the diagnostic armamentarium for sinus surgeons. Technological advancements such as intraoperative navigational devices depend on the surgeon's proper identification of normal or abnormal structures on CT or MRI scans.However, despite this technology's intent of reducing complications, failure to know the sinus anatomy or properly identify critical structures on the scan may still result in disastrous consequences. The frontal sinus hides in the anterior cranial vault surrounded by two thick layers of cortical bone. Its naturally draining "ostium", or frontal infundibulum, remains immersed in an intricate complex area covered by ethmoid cells and other anatomical structures that may not be so easy to find. In order to better understand frontal sinus anatomy, one must begin with its embryological development. © Springer-Verlag Berlin Heidelberg 2005.