Comparison between Three-Dimensional and Triplanar Computed Tomography Imaging of the Frontal Recess

Abstract

Despite advances in endoscopic surgical techniques, management of frontal sinus disease remains challenging. Much of this is related to the complex nature of frontal recess anatomy. A thorough understanding of frontal recess anatomy is paramount for the safety and success of frontal sinus surgery. Three-dimensional (3D) computed tomography (CT) may allow surgeons to obtain a more complete preoperative assessment of frontal recess anatomy. The purpose of this study was to determine if reconstructed 3D CT images as an adjunct to conventional triplanar imaging provide additional information regarding the frontal recess anatomy. A prospective study was performed. Two otolaryngologists reviewed the CT scans of 25 patients referred for routine paranasal sinus disease. The findings from review of the triplanar CT images were compared with the findings from review of the 3D reconstructions. Each study was assessed for (1) frontoethmoidal cells, (2) agger nasi cell, (3) subrabullar and frontal bullar cells, (4) intersinus septal cell, (5) superior uncinate process attachment site, and (6) and frontal sinus outflow tract. The examiners rated the usefulness of each study to identify each of the aforementioned anatomic subsites using a modified 5-point Likert scale. Intersinus septal cells, supraorbital ethmoid cells, and the anterior-posterior dimension of the frontal sinus outflow tract were better defined on the reconstructed 3D CT images. Three-dimensional CT is a useful adjunct to the conventional triplanar studies for the evaluation of frontal sinus and recess anatomy. This technique can define certain anatomic variants more effectively than 2D multiplanar reconstructed images.