title: Diagnostic performance of magnetic resonance imaging for acute pulmonary embolism: a systematic review and meta-analysis.
abstract: BACKGROUND
  With ongoing technical developments, magnetic resonance imaging (MRI) has notably evolved for the assessment of the pulmonary vasculature. However, uncertainty persists about the performance of MRI for the diagnosis of acute pulmonary embolism (APE).
  
  
  OBJECTIVE
  To clarify the comprehensive role of MRI in diagnosing APE.
  
  
  METHODS
  Studies were identified through a search of Pubmed and Ovid databases, and the QUADAS-2 tool was applied for quality assessment of the included studies.
  
  
  RESULTS
  Fifteen studies based on patients and nine based on vessels were retrieved. The patient-based analysis yielded an overall sensitivity of 0.75 (95% confidence interval, 0.70-0.79) and 0.84 (0.80-0.87) for all patients and patients with technically adequate images, respectively, with an overall specificity of 0.80 (0.77-0.83) and 0.97 (0.96-0.98) and a pooled diagnostic odds ratio (DOR) of 51.07 (18.36-142.05) and 155.22 (86.83-277.47). On average, MRI was technically inadequate in 18.89% of patients (range, 2.10%-27.70%). A direct comparison of different MRI modalities showed that the combined MRI test had the highest pooled DOR and the lowest proportion of inconclusive images. Of note, heterogeneity and moderate quality were observed. On a vessel basis, the MRI had high sensitivity and specificity in larger-order vessels, but a significantly lower sensitivity of 0.55 (0.50-0.60) for subsegmental APE.
  
  
  CONCLUSIONS
  On a patient-based level, MRI yields high diagnostic accuracy for the detection of APE, especially in technically adequate images, and the inconclusive MRI examinations mainly result from motion artifact and poor arterial opacification. The combined MRI test appears to be a more promising diagnostic tool with greater power of discrimination than single techniques. From a vessel-based perspective, MRI exhibits a high diagnostic capability with proximal arteries, but lacks sensitivity for peripheral embolism.
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: M
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Tumor Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: X
authors.initials: X
authors.lastname: Long
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: D
authors.initials: D
authors.lastname: Liu
authors.affiliation: Tumor Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: C
authors.initials: C
authors.lastname: Dong
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: X
authors.initials: X
authors.lastname: Kong
mesh_terms: D000208:Acute Disease; D019540:Area Under Curve; D016477:Artifacts; D016001:Confidence Intervals; D003287:Contrast Media; D005188:False Negative Reactions; D005189:False Positive Reactions; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging / Q000379:methods; D061330:Multidetector Computed Tomography; D064847:Multimodal Imaging; D016017:Odds Ratio; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: magnetic resonance angiography; magnetic resonance imaging; meta-analysis; multidetector computed tomography; pulmonary embolism