Low-dose noncontrast computed tomography in adults with acute appendicitis

Abstract

Background: Computed tomography (CT) is now considered the imaging modality of choice for acute abdomen. However, with the increasing concern for exposure to ionizing radiation and its related risk of cancer in long run, low-dose CT has come up in recent studies with the attempt to minimize the effective radiation dose, yet giving the similar diagnostic yield. Aim: The aim of this study was to evaluate the diagnostic performance of low-dose noncontrast multidetector CT in adult patients with suspected acute appendicitis in relation to patients' body mass index. Materials and Methods: Eighty-three adult patients with suspected acute appendicitis were subjected to both standard and low-dose abdominal noncontrast CT (NCCT). The images were interpreted independently by two radiologists (blinded). Data collected were summarized and statistically analyzed. P Results: With low-dose NCCT abdomen, appendix was visualized in 80 patients (96.4%), with nonvisualization in 3 patients (3.6%), which was similar to standard dose. Low-dose NCCT has an overall sensitivity of 98.2% and a specificity of 100% in the diagnosis of acute appendicitis. Only one false-negative case and zero false-positive case was found, considering 6 mm as the cutoff value in appendiceal diameter with associated fat stranding. Alternative diagnoses were found in 22 (10 females and 12 males) patients. Conclusion: Low-dose NCCT abdomen was found highly accurate in diagnosing acute appendicitis with achievement of significant radiation dose reduction (about 88%) and thus can be recommended as a fast, safe, and cost-effective initial imaging technique in patients with right lower quadrant pain.