A Feasibility Study of Real-Time Remote CT Reading for Suspected Acute Appendicitis Using an iPhone

Abstract

We aimed to evaluate the feasibility of an iPhone-based remote control system as a real-time remote computed tomography (CT) reading tool for suspected appendicitis using a third-generation (3G) network under suboptimal illumination. One hundred twenty abdominal CT scans were selected; 60 had no signs of appendicitis, whereas the remaining 60 had signs of appendicitis. The 16 raters reviewed the images using the liquid crystal display (LCD) monitor of a picture archiving and communication system (PACS) workstation, as well as using an iPhone connected to the PACS workstation via a remote control system. We graded the probability of the presence of acute appendicitis for each examination using a five-point Likert scale. The overall sensitivity and specificity for the diagnosis of suspected appendicitis using the iPhone and the LCD monitor were high, and they were not significantly different (sensitivity P = 1.00, specificity P = 0.14). The average areas under the receiver operating characteristic curves for all CT readings with the iPhone and LCD monitor were 0.978 (confidence interval 0.965-0.991) and 0.974 (0.960-0.988), respectively, and the two devices did not have significantly different diagnostic performances (P = 0.55). The inter-rater agreement for both devices was very good; the kappa value for the iPhone was 0.809 (0.793-0.826), and that for the LCD monitor was 0.817 (0.801-0.834). Each rater had moderate-to-very good intra-observer agreement between the two devices. We verified the feasibility of an iPhone-based remote control system as a real-time remote CT reading tool for identifying suspected appendicitis using a 3G network and suboptimal illumination.