Background:Multidetector computed tomography (MDCT) images for rhinosinusitis may have a risk of radiation hazards. Reduction in radiation dose may lead to a compromise in quality of MDCT images and have chances of postoperative complications.Objective:The aim of the study was to test the applicability of low-dose MDCT protocols for decision-making of sinus surgeries of patients with uncontrolled chronic rhinosinusitis.Design:Randomized, double-blind (patients and evaluators blind), controlled, trial.Setting:People's Hospital of Guanghan, China.Patients:A total of 288 patients with clinically confirmed uncontrolled chronic rhinosinusitis were subjected to randomization (1:1 ratio).Interventions:Patients were subjected to low-dose preoperative protocols of MDCT (n = 144; ldMDCT group) or standard-dose preoperative protocols of MDCT (n = 144; sdMDCT group).Outcome measures:Image analysis was performed by the workstation. Lund-Mackay score, modified Lund-Mackay score, estimated radiation exposure, and surgical complications were evaluated for each patient. The χ2 independent test or 2-tailed paired t test were performed for statistical analysis.Results:The preoperative MDCT images for standard-dose protocol had better quality than low-dose protocol (P < .001, q = 4.57). The area of images that give confidence for sinus surgery at one time was higher for standard-dose MDCT protocol technique than low-dose MDCT protocol method. Patients of ldMDCT group with large growth of nasal polyps (P = .03, q = 5.35) and complete opacification of sinuses (P = .03, q = 7.94) had complications after sinus surgeries. Either low-dose or standard-dose MDCT protocol was performed, the experience of otolaryngologist had decreased complication after surgeries.Conclusion:Preoperative low-dose MDCT should be used for diagnosis of uncontrolled chronic rhinosinusitis for decision making of sinus surgeries.Level of Evidence:III.Trial registration:researchregistry4264 dated 1 March 2016 (www.researchregistry.com).