Figure 5. Modern operating room set up for endoscopic endonasal surgery. Stereotactic navigation system shown to the left (A) and endoscopy screens in the center (B) facing the surgeon who will stand to the patient’s right just next to the shoulder. The patient is positioned supine in a beach chair position (C) with arms tucked and head in a skull clamp. Preoperative images may be stored and used for image guidance during operative procedures after configuring the navigation reference frame and registering the patient’s head using surface landmarks.