Flat Panel Cone Beam Computed Tomography of the Sinuses

Objective Flat panel cone beam CT is a relatively new technology that improves upon traditional multidetector CT scanners by generating images with greater spatial resolution at lower radiation doses. 1) Learn whether flat panel cone beam CT evaluation is an effective imaging modality for the sinuses. 2) Learn which doses of radiation provide quality evaluation of the sinuses while exposing the patient to the least amount of radiation. Methods In 2007, a panel consisting of neuroradiologists and otolaryngologists blindly reviewed images from flat panel sinus CTs (Xoran MiniCAT) of 11 live human subjects, each irradiated at all 3 different techniques (denoted as: low dose mAs=9.27, medium dose mAs = 18.41, high dose mAs=36.7) and rated the image quality of a pre-designated list of sinus anatomic structures. Techniques were compared in a pairwise manner using a Wilcoxon matched-pairs signed ranks test. Results Compared to the low dose technique CT scan, the high dose CT scan technique had significantly better image quality (P=.0029) and image noise (P=.0049). Similarly, the medium dose CT scan technique had significantly better image quality (P=.0020) and image noise (P = .0010) compared to the low dose technique. No difference in image quality and image noise existed between the medium and high dose techniques. No difference in visualization of 13 specific anatomic structures existed between any of the dose techniques. Conclusions Lower dose CT techniques achieved by flat panel cone beam CT may be an effective and safe alternative to traditional multidetector CT scanners. This imaging modality may help patients avoid unnecessary radiation to sensitive organs.