This site is targeted at medical and radiology professionals, contains user contributed content, and material that may be confusing to a lay audience. Use of this site implies acceptance of our Terms of Use.

Modified PIOPED criteria for diagnosis of PE

The modified PIOPED criteria for diagnosis of PE determine the probability of pulmonary emboli following a VQ scan :

Levels of probability

High probability
  • two or more large mismatched segmental defects or equivalent moderate/large defects with a normal x-ray
  • any perfusion defect substantially larger than radiographic abnormality
Intermediate probability
  • multiple perfusion defects with associated radiographic opacities
  • greater than 25% of a segment and less than two mismatched segmental perfusion defects with:
    • normal radiograph
    • one moderate segmental
    • one large or two moderate segmental
    • one large and one moderate segmental
    • three moderate segmental
  • triple match: solitary moderate-large matching segmental defect with matching radiograph
  • difficult to characterise as high probability or low probability
Low probability
  • nonsegmental defects - small effusion, blunting costophrenic angle, cardiomegaly, elevated diaphragm, ectatic aorta
  • any perfusion defect with substantially larger radiographic abnormality
  • matched ventilation and perfusion defects with normal chest radiograph
  • small subsegmental perfusion defects
Normal scan
  • no perfusion defects

Updating… Please wait.
Loadinganimation

Alert_accept

Error Unable to process the form. Check for errors and try again.

Alert_accept Thank you for updating your details.