Anatomical variants of paranasal sinus affecting the ostiomeatal unit

ABSTRACT

It is well known that anatomic variations affecting the ostiomeatal unit (OMU) become one of the causes of mucosal abnormalities of paranasal sinuses (PNS). Findings of coronal plane CT scans of PNS were analyzed in 95 patients with sinusitis or sinusitis-like complaints. Anatomical variations were seen in 88 cases of 60 patients. Mucosal abnormalities were seen in 27 of 47 cases with concha bullosa, 23 of 37 cases with enlarged ethmoid bulla, 8 of 33 cases with Agger nasi, 20 of 26 cases with nasoseptal deviation, 7 of 8 cases with Haller cell, 3 of 6 cases with duoble middle turbinate, 4 of 6 cases with medially bent uncinate process, 1 cases with laterally bent uncinate process, and 33 of 40 cases with mixed variations. Mucosal abnormalities in cases with antomical variations were detected in 61 cases, including maxillary sinus(51 cases), anterior ethmoid sinus (26 cases), frontal sinus (4 cases), and mixed (32 cases). Mucosal abnormalities without anatomical variations were detected in 13 cases involving maxillary sinuses (7 cases), anterior ethmoid sinuses (5 cases), and frontal sinus(1 cases). In conclusion, as coronal plane CT scan has the capability of dolineating anatomical variations and mucosal abnormalities of PNS, it is considered useful in evaluating the treatment and prognosis of chronic or recurrent sinusitis.