title: Silent pulmonary embolism in patients with distal deep venous thrombosis: systematic review.
abstract: OBJECTIVE
  The purpose of this investigation was to determine the prevalence of silent pulmonary embolism (PE) in patients with deep venous thrombosis (DVT) limited to the calf veins.
  
  
  METHODS
  This is a systematic review. We attempted to identify all published investigations that reported the prevalence of silent PE in patients with infrapopliteal DVT. Studies were identified by searching PubMed through January 2014. The search was augmented by manually reviewing the references in all original articles and in reviews.
  
  
  RESULTS
  The prevalence of silent PE in patients with DVT limited to the calf veins was described in 6 investigations. Pooled data showed a prevalence of 24 of 183 (13.1%) (95% CI 8.9-18.8%).
  
  
  CONCLUSIONS
  Silent PE in patients with DVT limited to the calf veins is not rare. Imaging at the time of diagnosis of calf vein DVT, typically with a perfusion scan alone, may be useful, but there is an economic cost and exposure to radiation.
authors.affiliation: Department of Osteopathic Medical Specialties, Michigan State University College of Osteopathic Medicine, East Lansing, Michigan, United States.
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Hughes
authors.affiliation: Department of Osteopathic Medical Specialties, Michigan State University College of Osteopathic Medicine, East Lansing, Michigan, United States. Electronic address: steinp@msu.edu.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Stein
authors.affiliation: Department of Osteopathic Medical Specialties, Michigan State University College of Osteopathic Medicine, East Lansing, Michigan, United States.
authors.forename: Fadi
authors.initials: F
authors.lastname: Matta
mesh_terms: D015984:Causality; D015897:Comorbidity; D006801:Humans; D015994:Incidence; D055420:Perfusion Imaging / Q000706:statistics & numerical data*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D011859:Radiography; D012307:Risk Factors; D020246:Venous Thrombosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*