A Comparison between Coronal and Axial Scans in PNS CT

ABSTRACT

BACKGROUND AND OBJECTIVES: A coronal section computerized tomography (CT) is essential for the diagnosis of paranasal sinusitis, especially in the evaluation of the ostiomeatal unit. Although the coronal scan is preferred to the axial scan, the role of the axial scan during endoscopic sinus surgery has not been thoroughly examined. The aim of this study is to compare the advantages and disadvantages of coronal and axial scans in the paranasal sinuses. MATERIALS AND METHODS: Selected for study were the coronal and axial scans of 30 preoperative sinus CTs showing minimal sinus pathology. The rates of detecting 15 anatomic structures in the coronal and axial sections were analyzed across 60 sides. RESULTS: The coronal scan was superior to the axial scan in detecting eight normal structures, including the anterior ethmoid artery, the opening of the maxillary sinus and the superior meatus (p<0.05). The axial scan was useful in showing the vertical portion of the 3rd basal lamella and the opening and the anterior wall of the sphenoid sinus (p<0.05). CONCLUSION: The coronal scan is more informative than the axial scan but has limitations in showing the structures lying on the coronal plane. The axial scan plays a complementary role in covering this limitation. Together, the coronal and axial sections of a sinus CT can help the surgeon to understand the three dimensional structure of the paranasal sinus before endoscopic sinus surgery.