Does clinical pretest probability influence image quality and diagnostic accuracy in dual-source coronary CT angiography?
OBJECTIVE
To prospectively evaluate the influence of the clinical pretest probability assessed by the Morise score onto image quality and diagnostic accuracy in coronary dual-source computed tomography angiography (DSCTA).


METHODS
In 61 patients, DSCTA and invasive coronary angiography were performed. Subjective image quality and accuracy for stenosis detection (>50%) of DSCTA with invasive coronary angiography as gold standard were evaluated. The influence of pretest probability onto image quality and accuracy was assessed by logistic regression and chi-square testing. Correlations of image quality and accuracy with the Morise score were determined using linear regression.


RESULTS
Thirty-eight patients were categorized into the high, 21 into the intermediate, and 2 into the low probability group. Accuracies for the detection of significant stenoses were 0.94, 0.97, and 1.00, respectively. Logistic regressions and chi-square tests showed statistically significant correlations between Morise score and image quality (P < .0001 and P < .001) and accuracy (P = .0049 and P = .027). Linear regression revealed a cutoff Morise score for a good image quality of 16 and a cutoff for a barely diagnostic image quality beyond the upper Morise scale.


CONCLUSIONS
Pretest probability is a weak predictor of image quality and diagnostic accuracy in coronary DSCTA. A sufficient image quality for diagnostic images can be reached with all pretest probabilities. Therefore, coronary DSCTA might be suitable also for patients with a high pretest probability.
Thomas
Christoph
C
Department of Diagnostic and Interventional Radiology, University of Tübingen, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. Christoph.thomas@med.uni-tuebingen.de
Brodoefel
Harald
H
Tsiflikas
Ilias
I
Bruckner
Friederike
F
Reimann
Anja
A
Ketelsen
Dominik
D
Drosch
Tanja
T
Claussen
Claus D
CD
Kopp
Andreas
A
Heuschmid
Martin
M
Burgstahler
Christof
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods*