Computed tomography scans of paranasal sinuses before functional endoscopic sinus surgery.

This review aims to familiarize the radiologist with the common types of sinus surgery including their indications and techniques. We also illustrate how surgeons interpret 3D sinus anatomy when evaluating computed tomography (CT) studies. Preoperative evaluation by CT is mandatory for all patients undergoing functional endoscopic sinus surgery (FESS). In the past decade in particular, CT of the paranasal sinuses has become a roadmap for FESS. The radiologist's goal is to report on five key points: the extent of sinus opacification, opacification of sinus drainage pathways, anatomical variants, critical variants, and condition of surrounding soft tissues of the neck, brain and orbits. We present a systematic approach to the use of coronal, axial, and sagittal images in CT evaluation before FESS.