Related Experiment Videos
Suspected pulmonary embolism: prospective evaluation with pulmonary MR angiography
M L Schiebler1, G A Holland, H Hatabu
1Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia.
Purpose:
To prospectively evaluate three magnetic resonance (MR) imaging techniques for detection of pulmonary embolism.
Materials And 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.
Conclusion:
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.