在进行功能性内窥镜上颌窦手术中确认上颌窦自然开口极为重要。进行鼻道镜检时 ,上颌窦自然开口通常位于筛漏斗钩突外侧。虽然存在副口 (常位于鼻外侧壁 ) ,但自然开口极难直接直视。开窗术中查明自然开口 ,并需切除钩突。本例 ,0°镜所见之左上颌窦自然开口的异常像 ,容易辨于 In the functional endoscopic maxillary sinus surgery to confirm the natural opening of the maxillary sinus is extremely important. Nasal sinus surgery, the natural opening of the maxillary sinus usually located in the hook funnel outside the screen. Although there are deputy port (often located in the lateral wall of the nose), but the natural opening is very difficult to directly look. Window opening to identify natural openings, and need to remove the uncinate process. In this case, 0 ° mirror see the natural image of the left maxillary sinus abnormalities, easy to distinguish