Using CT scan, we studied the influence of the most important sinonasal anatomic variants on 112 patients, aged more than 16 years, suffering from recurrent, persistent or chronic sinusitis. The series was characterized by the absence of: multifocal sinusitis, polyposis, dental or mycotic sinusitis, traumatic, tumour, actinic or prior surgery. We compared our results with those of the literature. Our findings confirmed the association between recurrent, persistent or chronic sinusitis, and ipsilateral septal ridges or spurs (33%), unusual ipsilateral deflexions of uncinate process (31%), and contralateral septal watch glass like deviation (42%). We found no correlation for the other studied variants (concha bullosa, paradoxical curve of middle turbinate, pneumatised uncinate process, hypertrophic ethmoid bulla, Haller cell and accessory maxillary ostium).