Antroscopy has an established role in the diagnosis of maxillary sinus disease; however, its role in overall patient management requires clarification if it is to be widely adopted as an outpatient procedure. This study examined 100 consecutive attenders to an antroscopy clinic and monitored their diagnosis and management plan both before and after antroscopy. Diagnosis was altered or added to in 79% of cases and management in 73% of cases. The trend after knowledge of antroscopic findings was towards more medical treatment and less surgical intervention. Such a change would clearly have significant resource implications. While computed tomographic scanning time is limited, outpatient sinus endoscopy can be used as an intermediate investigation, with only selected patients going forward to be more comprehensively investigated.