“…These anatomic reference points, which are vital for maintaining the proper surgical orientation away from critical orbital and skull base structures, include the uncinate process, ostium of the maxillary sinus, middle and superior turbinate and surrounding recesses, basal lamella of the middle and superior turbinates, the anterior ethmoid artery, and the anterior and posterior ethmoid air cells. 5–11 However, in real life situations, these landmarks often have significant anatomic variations or are obscured by blood, polyps, and/or other inflammatory or postsurgical changes. Failure to correctly identify these landmarks in these unfamiliar circumstances can misdirect the surgeon with disastrous consequences for the patient.…”