title: Diagnostic accuracy of three-dimensional contrast-enhanced MR angiography at 3-T for acute pulmonary embolism detection: comparison with multidetector CT angiography.
abstract: BACKGROUND
  Three-dimensional contrast-enhanced MR pulmonary angiography (MRPA) is a suitable option for pulmonary embolism (PE) detection. However, there have been few reports on the diagnostic accuracy of MRPA for PE detection in a 3-T MR system. The purpose of this study was to evaluate the accuracy of MRPA in a 3-T MR system to detect acute PE with multidetector CT pulmonary angiography (CTPA) as reference standard.
  
  
  METHODS
  Twenty-seven patients (18 males and 9 females, mean age 38.9±14.4 years) underwent both MRPA and CTPA within 3 days (range, 0-3 days) for evaluating PE. Pulmonary emboli in MRPA were independently analyzed on a per-patient and per-lobe basis by two radiologists. CTPA was regarded as reference standard, which was evaluated by another two radiologists in consensus. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for PE detection were calculated. Weighted κ values were calculated to evaluate agreement between readers.
  
  
  RESULTS
  Twenty-four patients had PE in 55 lung lobes in CTPA, while 3 patients had no PE detected. Readers 1 and 2 correctly detected 47 and 46 lung lobes having clots in 24 and 23 patients, corresponding to sensitivities, specificities, PPV, NPV, and accuracies of 100%, 100%, 100%, 100%, 100%; 100%, 66.7%, 96.0%, 100%, 96.4% on a per-patient basis and 85.5%, 100%, 100%, 90.9%, 94.1%; 83.6%, 93.7%, 90.2%, 89.2%, 89.6% on a per-lobe basis; respectively. Excellent inter-reader agreement (κ values=1.00 and 0.934; both P<0.001) were found for detecting PE on a per-patient and per-lobe analysis.
  
  
  CONCLUSIONS
  Three-dimensional contrast-enhanced MRPA with a 3-T MR system is a suitable alternative modality to CTPA to detect PE on a per-patient basis based on this small cohort study.
authors: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China. Electronic address: kevinzhlj@163.com.
authors: Long Jiang
authors: LJ
authors: Zhang
authors: Song
authors: S
authors: Luo
authors: Benjamin M
authors: BM
authors: Yeh
authors: Chang Sheng
authors: CS
authors: Zhou
authors: Chun Xiang
authors: CX
authors: Tang
authors: Yan'e
authors: Y
authors: Zhao
authors: Lin
authors: L
authors: Li
authors: Ling
authors: L
authors: Zheng
authors: Wei
authors: W
authors: Huang
authors: Guang Ming
authors: GM
authors: Lu
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D011655:Pulmonary Embolism / Q000175:diagnosis*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult
keywords: Magnetic resonance imaging; Pulmonary embolism; Tomography, X-ray computed