title: Detection of pulmonary embolism during pregnancy: comparing radiation doses of CTPA and pulmonary scintigraphy.
abstract: OBJECTIVE
  In pregnant patients pulmonary embolism is a common occurrence with potentially devastating outcomes, necessitating timely imaging diagnosis. In every patient, especially in pregnant patients, radiation exposure is an important consideration while selecting the best imaging modality.
  
  
  METHODS
  We performed a retrospective analysis comparing radiation doses of computed tomography pulmonary angiography (CTPA), perfusion scintigraphy, and perfusion/ventilation scintigraphy for suspected pulmonary embolism in 53 pregnant patients at our hospital between 2006 and 2012. Effective dose and breast-absorbed and uterus-absorbed doses for CTPA as well as effective dose and breast and fetus-absorbed doses for pulmonary scintigraphy were estimated using International Commission on Radiological Protection 103 weighting factors.
  
  
  RESULTS
  For CTPA and perfusion scintigraphy, average doses were estimated as effective doses of 21 and 1.04 mSv, breast-absorbed doses of 44 and 0.28 mGy, and uterus-absorbed dose of 0.46 mGy and fetal-absorbed dose of 0.25 mGy, respectively. With inclusion of the ventilation component of pulmonary scintigraphy, doses increased to an effective dose of 1.29 mSv, a breast-absorbed dose of 0.37 mGy, and a fetal-absorbed dose of 0.40 mGy.
  
  
  CONCLUSIONS
  Perfusion nuclear medicine study has a statistically significantly lower effective and breast-absorbed dose (P<0.0001) when compared with CTPA. Similarly, the fetal-absorbed dose for pulmonary scintigraphy has a statistically lower dose (P=0.0010) when compared with CTPA, even if the ventilation component of pulmonary scintigraphy is performed, although these values are so small that they are unlikely to be clinically significant.
authors.affiliation: Department of Radiology, Henry Ford Hospital, Detroit, Michigan, USA.
authors.forename: Seyed A
authors.initials: SA
authors.lastname: Astani
authors.forename: Leah C
authors.initials: LC
authors.lastname: Davis
authors.forename: Beth A
authors.initials: BA
authors.lastname: Harkness
authors.forename: Mark P
authors.initials: MP
authors.lastname: Supanich
authors.forename: Ishani
authors.initials: I
authors.lastname: Dalal
mesh_terms: D000792:Angiography / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D009035:Mothers; D058958:Organs at Risk / Q000528:radiation effects; D011247:Pregnancy; D011248:Pregnancy Complications / Q000000981:diagnostic imaging*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011829:Radiation Dosage; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity