Flat panel cone beam computed tomography of the sinuses.

OBJECTIVE: This study aims to compare the image quality and potential diagnostic accuracy of paranasal sinus CT scans generated by flat panel cone beam CT at three specific data acquisition times.

STUDY DESIGN: Prospective, single blinded analysis.

SUBJECTS AND METHODS: Eleven patients without previous radiologic evaluation were selected based on history and findings suspicious for chronic sinusitis. Each patient was scanned at three different acquisition times: 10, 20, and 40 seconds. A panel of neuroradiologists and otolaryngologists, blinded to the scan acquisition time, individually reviewed images and rated overall image quality and visualization of specific anatomic sites. Image noise values were also calculated. Techniques were compared with a Wilcoxon matched-pairs signed ranks test.

RESULTS: Compared to the 10-second acquisition time, the 40- and 20-second acquisition time techniques had significantly better image quality (P < 0.05) and image noise (P < 0.05). No difference in image quality and image noise existed between the 20- and 40-second techniques. No difference in visualization of specific anatomic structures existed between any of the time techniques.

CONCLUSION: The quality of flat panel CT imaging of the sinuses directly relates to scan time and thus radiation dose.