Performance of radiographers in the evaluation of CT colonographic images.
OBJECTIVE
The purpose of this study was to compare the accuracy of radiographers with that of radiologists in the interpretation of CT colonographic images.


METHODS
Four observers (a radiologist, a radiologist in training, and two radiographers) evaluated 145 data sets using a primary 3D approach. The radiographers were part of our CT colonography work group and underwent training that consisted of 20 cases. The reference standard was optical colonoscopy with second-look colonoscopy for discrepant lesions > or = 10 mm in diameter. Mean sensitivities per patient and per polyp stratified for size (any size, > or = 6 mm, and > or = 10 mm) was determined for the radiologists and radiographers. Specificity was determined on a per-patient basis.


RESULTS
At colonoscopy in 86 of 145 patients, a total of 317 polyps were found (60 polyps > or = 6 mm in 26 patients and 31 polyps > or = 10 mm in 18 patients). No statistically significant differences were found in detection rates between radiologists and radiographers. Sensitivities for patients with a lesion of any size (66% for radiologists vs 65% for radiographers), > or = 6 mm (81% vs 87%), and > or = 10 mm (both 78%) were similar for all observers. On a per-polyp basis, detection rates were equivalent regardless of polyp size (47% vs 40%), for lesions > or = 6 mm (71% vs 65%), and for lesions > or = 10 mm (69% vs 66%). Mean specificities were similar among patients without lesions (31% vs 30%), patients without lesions > or = 6 mm (71% vs 67%), and patients without lesions > or = 10 mm (93% vs 93%).


CONCLUSIONS
Radiographers with training in CT colonographic evaluation achieved sensitivity and specificity in polyp detection comparable with that of radiologists. Radiographers can be considered reviewers in the evaluation of CT colonographic images.
Jensch
Sebastiaan
S
Department of Radiology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, Noord-Holland, The Netherlands. s.jensch@amc.uva.nl
van Gelder
Rogier E
RE
Florie
Jasper
J
Thomassen-de Graaf
Marloes A
MA
Lobé
Jack V
JV
Bossuyt
Patrick M M
PM
Bipat
Shandra
S
Nio
C Yung
CY
Stoker
Jaap
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D023881:Colonography, Computed Tomographic / Q000706:statistics & numerical data*; D003113:Colonoscopy / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D015588:Observer Variation; D011361:Professional Competence / Q000706:statistics & numerical data*; D011871:Radiology / Q000706:statistics & numerical data*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013647:Task Performance and Analysis