Acute pulmonary embolism: diagnosis with MR angiography.
OBJECTIVE
To prospectively evaluate pulmonary magnetic (MR) angiography as a diagnostic examination for acute pulmonary embolism (PE).


METHODS
Thirty-six consecutive patients (19 women, 17 men; age range, 28-84 years) underwent pulmonary digital subtraction angiography (DSA) and pulmonary MR angiography. MR angiograms were obtained during suspended respiration and the pulmonary arterial phase of gadolinium-based contrast medium injection. A steady-state gradient-recalled-echo sequence with free induction decay sampling was used. DSA studies were interpreted for the presence of acute PE by two independent radiologists; an adjudicator made the final decision on discordant interpretations.


RESULTS
By using DSA, a total of 19 acute pulmonary emboli were depicted in 13 patients. Prospectively, 13 of these emboli were depicted by using MR angiography. MR angiography missed six emboli: Four required the DSA adjudicator to make the decision, and one was in a patient whose MR angiogram was acquired during breathing. Four of these six emboli were small subsegmental emboli, and two were segmental.


CONCLUSIONS
Performed without pulmonary arterial catheterization, iodinated contrast media, or ionizing radiation, pulmonary MR angiography had a high accuracy for depicting lobar and segmental emboli, but was unable to depict four of five subsegmental emboli.
Gupta
A
A
Department of Radiology, Sir Charles Gairdner Hospital, Queen Elizabeth II Medical Centre, Nedlands, Western Australia.
Frazer
C K
CK
Ferguson
J M
JM
Kumar
A B
AB
Davis
S J
SJ
Fallon
M J
MJ
Morris
I T
IT
Drury
P J
PJ
Cala
L A
LA
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007275:Injections, Intravenous; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000473:pathology; D011655:Pulmonary Embolism / Q000175:diagnosis*; D012680:Sensitivity and Specificity
D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA