Usefulness of reversed display of soft-copy abdominal radiographs for urinary calculi detection.
OBJECTIVE
To determine the usefulness of reversed display of soft-copy abdominal radiographs for urinary calculi detection.


METHODS
Sixty radiographs with a single urinary calculus less than 5 mm in the long diameter (15 in the kidney; 15 in the proximal ureter; 15 in the mid-ureter, 15 in the distal ureter) and 15 radiographs without calculi were evaluated. Four readers blinded to the presence or absence of urinary calculi on each radiograph reviewed the radiographs in the conventional display, reversed display, and combination of conventional and reversed displays at 1-week intervals. All images were evaluated in random order and the presence or absence of urinary calculi was interpreted using the confidence score from 1 to 5.


RESULTS
Multireader analysis for calculi in all locations showed a greater area under the receiver operating curve for combination of the two displays (0.764) than for the conventional display alone (0.655) (P=0.031). In the single-reader analysis for calculi in all locations, the third reader showed a greater area under the receiver operating curve for the reversed display (0.784) than for the conventional display (0.622) (P=0.027). Multireader analysis of the calculi in the kidney showed a greater area under the receiver operating curve for combination of the two displays (0.824) than for the conventional display alone (0.703) (P=0.043).


CONCLUSIONS
The reversed display of soft-copy abdominal radiographs may be useful for urinary calculi detection.
Kang
S S
SS
Department of Radiology, Sungkyunkwan University School of Medicine, Samsung Medical Center, Kangnam-gu, Seoul, South Korea.
Kim
J K
JK
Ryu
J A
JA
Choi
N
N
Bae
S J
SJ
Kim
B
B
D019540:Area Under Curve; D006801:Humans; D007669:Kidney Calculi / Q000000981:diagnostic imaging*; D015588:Observer Variation; D012372:ROC Curve; D011860:Radiography, Abdominal; D011873:Radiology Information Systems; D014057:Tomography, X-Ray Computed; D014514:Ureteral Calculi / Q000000981:diagnostic imaging*