Improved inspection of the lateral pharyngeal recess using cone-beam computed tomography in the upright position

ObjectivesTo evaluate the structure of the lateral pharyngeal recess (LPR) and surrounding structures in computed tomography (CT) images obtained from subjects in the supine and upright positions.MethodsSix subjects were evaluated using cone-beam CT (CBCT) in the upright position, and with a four-row multidetector helical CT (MDCT) in the supine position. All of the voxel sizes were adjusted to 0.3 × 0.3 × 0.3 mm3 in the x, y, z coordinate system. The posterior nasal spine and basion were used as references. The LPR and surrounding structures were measured and compared in the two different modalities.ResultsIn 83% of the cases, the LPR was deeper when the position was changed from supine to upright.ConclusionsOur results suggest that imaging of the LPR using CBCT with the subject in the upright position is superior to that using MDCT with the subject in the supine position.

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