A Study Of Improving The Detection Mode Of CT Pulmonary Nodules By Computer Aided Detection

Objective: By comparing concurrent-reader and second-reader modes of compu ter-aided detection(CAD) for screening pulmonary nodules,the purpose of this study is to investigate a possible modes for CAD, which can be widely applied in the clinic.Methods: 60 subjects diagnosed with lung nodules undergoing the rountine-d ose screening CT examination were selected.Four radiologists independently interpre ted these datasets three times and marked all detected nodules and recorded the rea ding time simultaneously.For the first time, these radiologists read these scans with out CAD;The second time, CAD as concurrent readers helped them reading scans.The last time, CAD used as the second reader assisted these radiologists reading scans.The ground truth of nodules in the datasets was determined by three raiologist-s. 2?test and rank-sum test were performed to test whether there is significant dif-ference between sensitivities of two reading modes, and statistical significances we-re defined as P<0.05. Results: The three radiologists found 253 nodules.The sens-itivities of pulmonary nodule detection with CR(87.75%,P<0.001)and SR(88.84%,P<0.001)were significantly higher than the sensitivity of pulmonary nodule de-tection without CAD(68.58%).There were no significant sensitivity diffrernce betwe-en CR and SR(P=0.30).The reading time was significantly less in CR mode(97±38s) than in independently reading(128± 45 s, P<0.001) and SR mode(169±53s, P<0.01).Conclusion: Two reading modes of CAD(CR, SR) can significantly increa-se the sensitivities of radiologists. The efficiency is higher by CR than by SR.C R can be used as the first option to detect pulmonary nodules by radiologists.