RESULTS Obstruction of frontal sinus ostium was found in all cases.The frontal sinus ostia were obstructed by swelling mucosa, polypid mucosa or over developed cells.

• 结果38例患者均为额窦口阻塞，原因分别为额窦口被肿胀黏膜、息肉样变黏膜和过度发育气房阻塞，额窦引流受阻引发额窦炎。