Suspected pulmonary embolism: prospective evaluation with pulmonary MR angiography.
OBJECTIVE
To prospectively evaluate three magnetic resonance (MR) imaging techniques for detection of pulmonary embolism.


METHODS
Eighteen patients in whom the presence of acute or chronic pulmonary emboli was suspected underwent examination with the following pulse sequences: cardiac-gated spin echo, cine spatial modulation of magnetization, and two-dimensional time-of-flight pulmonary breath-hold (PBH) MR angiography. Three radiologists independently and blindly reviewed each case and graded a total of 518 arterial segments for each pulse sequence with a continuous scale of 0%-100% for likelihood of pulmonary embolism.


RESULTS
The overall sensitivity of PBH MR angiography for detection of acute pulmonary emboli was 0.85; for chronic emboli, which were smaller in anteroposterior (AP) diameter, the overall sensitivity was 0.42. Emboli larger than 1 cm in AP diameter were typically identified with > 75% confidence with all pulse sequences.


CONCLUSIONS
Acute pulmonary emboli greater than 1 cm in AP diameter were as accurately identified on PBH MR angiograms obtained in 15 seconds as they were on MR images obtained with longer pulse sequences not dependent on breath holding.
Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia.
M L
ML
Schiebler
G A
GA
Holland
H
H
Hatabu
J
J
Listerud
T
T
Foo
H
H
Palevsky
H
H
Edmunds
W B
WB
Gefter
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001158:Arteries; D002908:Chronic Disease; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008168:Lung / Q000098:blood supply; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009040:Motion Pictures; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000473:pathology; D012372:ROC Curve; D012039:Regional Blood Flow; D012680:Sensitivity and Specificity