Evaluating "eee" phonation in multidetector CT of the neck

Abstract

BACKGROUND AND PURPOSE: Since the advent of pharyngography, "eee" phonation has been used to distend the airway during imaging. When imaging shifted to axial CT, "eee" phonation was used to delineate mucosal anatomy better. However, because patients could not phonate for the entire examination (which could take several minutes), the technique was only useful during supplemental imaging, performed after the primary acquisition through the neck. The supplemental images covered a limited area (usually the larynx or supraglottis) and, therefore, could be obtained while patients phonated. Imaging of the neck has now shifted to multidetector CT (MDCT). With a 64-detector MDCT, the entire neck can be imaged in 8 seconds. We evaluated whether "eee" phonation could be used during the entire acquisition through the neck without degrading image quality. MATERIALS AND METHODS: Forty-eight patients who performed "eee" phonation during a CT examination of the neck were compared with 96 patients scanned following a breath-hold command. All patients were scanned on the same 64-detector MDCT scanner after intravenous contrast administration. Images were acquired at a 2-mm section thickness and reconstructed at 1-mm intervals. All scanning times ranged from 5 to 7 seconds. Studies were evaluated separately by 2 neuroradiologists for image degradation due to motion. Statistical analysis was performed by using the proportional odds ratio. RESULTS: We found no significant difference in motion during phonation compared with the breathhold technique. CONCLUSIONS: Our results indicate that "eee" phonation can be performed during an entire image acquisition through the neck, when performed with the speed of the 64-detector scanner, without increasing motion.