title: Resolution of pulmonary embolism on CT pulmonary angiography.
abstract: OBJECTIVE
  The objective of our study was to retrospectively determine the rate of resolution of pulmonary emboli (PEs) in individual vessels and the rate of complete resolution of PEs on CT angiography.
  
  
  METHODS
  Follow-up CT pulmonary angiograms, obtained during the period from January 2006 through May 2009, of 69 patients with acute PE from two hospitals were assessed. Initial and follow-up CT angiograms were reread together by one radiologist at both of the hospitals. Images were obtained using a 10-, 16-, 40-, or 64-MDCT angiography unit with a 0.5-mm collimation, 1.25- to 2.0-mm reconstruction, 0.3- to 0.5-second rotation time, and 7.5-mm/rotation table speed. All CT angiograms were obtained using a PE protocol.
  
  
  RESULTS
  Follow-up CT angiograms were obtained in 35 men and 34 women who ranged in age from 17 to 92 years (mean age, 58 +/- 17 [SD] years). Complete CT angiographic resolution of PE was seen in six of 15 patients (40%) 2-7 days after diagnostic imaging. After day 28, complete resolution occurred in 17 of 21 patients (81%). The main pulmonary arteries showed complete PE resolution during days 2-7 in seven of nine patients (78%) and after day 28 in 34 of 36 (94%). The lobar pulmonary arteries showed complete resolution of PE during days 2-7 in 23 of 33 patients (70%) and after 28 days in 44 of 48 (92%). The segmental pulmonary arteries showed complete resolution during days 2-7 in eight of 21 patients (38%) and after day 28 in 38 of 38 (100%).
  
  
  CONCLUSIONS
  Most patients (81%) showed complete resolution of PE on CT angiography after 28 days. PEs resolved faster in the main and lobar pulmonary arteries than in the segmental branches.
authors.affiliation: Department of Internal Medicine, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 44405 Woodward Ave, Pontiac, MI 48341-5023, USA. steinp@trinity-health.org
authors.forename: Paul D
authors.initials: PD
authors.lastname: Stein
authors.forename: Abdo Y
authors.initials: AY
authors.lastname: Yaekoub
authors.forename: Fadi
authors.initials: F
authors.lastname: Matta
authors.forename: Muhammad
authors.initials: M
authors.lastname: Janjua
authors.forename: Rushi M
authors.initials: RM
authors.lastname: Patel
authors.forename: Lawrence R
authors.initials: LR
authors.lastname: Goodman
authors.forename: Martin L
authors.initials: ML
authors.lastname: Gross
authors.forename: James E
authors.initials: JE
authors.lastname: Denier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult