McGregor line

The McGregor line is a modification of the Chamberlain line and is used in the evaluation of basilar invagination when the opisthion is not identified on plain radiographs.

It refers to a line connecting posterior edge of the hard palate to the most caudal point of the occipital curve. If the tip of the dens lies more than 4.5 mm above this line it is indicative of basilar invagination.

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Article information

rID: 22817
Section: Approach
Tags: stub, refs, cases
Synonyms or Alternate Spellings:
  • McGregor lines

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