Multidetector computed tomography for acute pulmonary embolism.
BACKGROUND
The accuracy of multidetector computed tomographic angiography (CTA) for the diagnosis of acute pulmonary embolism has not been determined conclusively.


METHODS
The Prospective Investigation of Pulmonary Embolism Diagnosis II trial was a prospective, multicenter investigation of the accuracy of multidetector CTA alone and combined with venous-phase imaging (CTA-CTV) for the diagnosis of acute pulmonary embolism. We used a composite reference test to confirm or rule out the diagnosis of pulmonary embolism.


RESULTS
Among 824 patients with a reference diagnosis and a completed CT study, CTA was inconclusive in 51 because of poor image quality. Excluding such inconclusive studies, the sensitivity of CTA was 83 percent and the specificity was 96 percent. Positive predictive values were 96 percent with a concordantly high or low probability on clinical assessment, 92 percent with an intermediate probability on clinical assessment, and nondiagnostic if clinical probability was discordant. CTA-CTV was inconclusive in 87 of 824 patients because the image quality of either CTA or CTV was poor. The sensitivity of CTA-CTV for pulmonary embolism was 90 percent, and specificity was 95 percent. CTA-CTV was also nondiagnostic with a discordant clinical probability.


CONCLUSIONS
In patients with suspected pulmonary embolism, multidetector CTA-CTV has a higher diagnostic sensitivity than does CTA alone, with similar specificity. The predictive value of either CTA or CTA-CTV is high with a concordant clinical assessment, but additional testing is necessary when the clinical probability is inconsistent with the imaging results.
Stein
Paul D
PD
Department of Research, St. Joseph Mercy Oakland Hospital, Pontiac, Mich, USA. steinp@trinity-health.org
Fowler
Sarah E
SE
Goodman
Lawrence R
LR
Gottschalk
Alexander
A
Hales
Charles A
CA
Hull
Russell D
RD
Leeper
Kenneth V
KV
Popovich
John
J
Quinn
Deborah A
DA
Sos
Thomas A
TA
Sostman
H Dirk
HD
Tapson
Victor F
VF
Wakefield
Thomas W
TW
Weg
John G
JG
Woodard
Pamela K
PK
D000208:Acute Disease; D003287:Contrast Media / Q000009:adverse effects; D005260:Female; D006801:Humans; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D010690:Phlebography / Q000379:methods; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D011655:Pulmonary Embolism / Q000150:complications / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000009:adverse effects / Q000379:methods*; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000000981:diagnostic imaging*
D003287:Contrast Media