lxd2018rsna@163.com

2 reading modes of CAD(CR, SR) can significantly increase the sensitivities of RFD of radiologists. The reading time is shorter by CR than by SR.CR mode can be used as the first option to detect rib fracture by radiologists.

To assess the effect of rib fracture computer-aided diagnosis(CAD) on diagnosis of radiologist.

85 trauma CTs(50 males) with follow-up review CTs were included in the retrospective study.All trauma CTs were subjected to CAD system to generate rib fracture bounding box.The procedure of the CAD system contains ribs segmentation, centerline extraction,rib fracture detection(RFD) based on deep learning algorithm(Faster RCNN),false positive removal and rib fracture localization. 2 senior(NO.1,2) and 2 junior radiologists(NO.3,4) independently evaluated the data using 3 reading modes(without CAD,CR,SR).The fracture line or bone callus growth is the criterion for determining the rib fracture.The follow-up review CTs verified the diagnosis of rib fracture and established the reference standard[1].All fractures detected by the 4 readers were compared to the reference standard. χ^2 test and rank-sum test were performed to test whether there was significant difference between sensitivities and reading times of 3 reading modes.Abbreviations:without CAD:Radiologists independently evaluated the data.CR:Radiologists apply CAD system as a concurrent reader(CR) to evaluate the data.SR:Radiologists evaluate the data as a first reader and then apply the CAD system as a second reader(SR) to review the results.

The reference standard identified 281 rib fractures in 85 patients.The sensitivity of RFD with SR 97.2%(273/281;P<0.001) and CR 96.4%(271/281;P<0.001) were significantly higher than that of without CAD 89.7%(252/281).There was no significant sensitivity difference between CR and SR(P>0.3). Senior and junior radiologists used CAD as CR or SR and there was no significant sensitivity difference between 2 modes(P=0.067,P=0.067).Reading time was significantly shorter for CR(98s) compared to that of without CAD(148s;P<0.001) and SR(169s;P<0.001).Reading time of the 3 modes was less in the senior group than in the junior group with significant differences(P<0.001).