Basion-dens interval

Dr Craig Hacking et al.

The basion-dens interval (BDI), as the name suggests, is the distance between the basion and the tip of the dens, used in the diagnosis of atlanto-occipital dissociation injuries.

It is the distance from the most inferior portion of the basion to the closest point of the superior aspect of the dens in the median (midsagittal) plane.

Normal values are < 12mm on plain radiographs and <8.5mm on CT 1.

See also

 

Share article

Article Information

rID: 40481
Section: Gamuts
Synonyms or Alternate Spellings:
  • BDI
  • Basion-dens interval (BDI)

Support Radiopaedia and see fewer ads

Cases and Figures

  • Drag
    Base of skull lines
    Drag here to reorder.
  • 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.