Reliability of High-Pitch Ultra-Low-Dose Paranasal Sinus Computed Tomography for Evaluating Paranasal Sinus Anatomy and Sinus Disease

Objectives: The aim of this study was to evaluate the reliability of high-pitch ultra-low-dose computed tomography (CT) for detecting important paranasal sinus anatomic landmarks and pathologies. Materials and Methods: Sixty patients (22 females, 38 males) aged 15 to 67 years (mean age, 33.68 y; SD, 9.83 y) underwent high-pitch ultra-low-dose CT of the paranasal sinuses between February and June 2012. To determine the lowest possible dose for evaluation of the paranasal sinuses, the patients were divided into three groups randomly and prospectively. A different low-dose CT protocol was applied to each group. The image quality was assessed subjectively by a radiologist and an otorhinolaryngology head and neck surgeon independently using a 4-point grading scale (0 = structures could not be identified, 1 = indistinctly defined structures, 1.5 = relatively well-defined structures, 2 = very well-defined structures). Anatomic landmarks and mucosal structures were evaluated. Mean scores were evaluated to assess statistical significance. Results: According to the anatomic landmark scoring, excluding the ethmoid foramen for ethmoid artery identification, all of the structures in all 3 groups were very well-defined structures. The ethmoid foramen for ethmoid artery identification was scored as either could not be identified or an indistinctly defined structure in all groups. On evaluating the mucosa of the paranasal sinuses, normal and pathologic mucosal structures were scored as very well defined in all of the patients. The interobserver agreement was excellent. Conclusion: High-pitch ultra-low-dose CT is a safe, reliable paranasal sinus screening tool.