Abstract
Two types of newly developed 14-membered macrolides were administered to 31 patients with chronic sinusitis for 2 to 3 months. The clinical efficacy was compared with effects of macrolides on the patency of ostiomeatal unit (OM unit) revealed by CT scan and the size of nasal polyps. The final efficacy was 38.4%. Non-responder to macrolide treatment tended to show a complete obstruction of the OM unit. In patients with severe obstruction of the OM unit. The presence of large nasal polyps in the middle nasal meatus seems to be a critical factor of cause resistance to the macrolides.