Skull base angle

Dr Varun Babu and Dr Jeremy Jones et al.

The skull base angle allows the diagnosis of platybasia and basilar kyphosis. There are several different techniques that may be used on sagittal images from MRI or CT.

Standard technique

Angle formed by:

  1. line joining the nasion with the centre of the pituitary fossa
  2. line joining the anterior border of the foramen magnum with the centre of the pituitary fossa
  • normal: 125°-143°
  • platybasia: >143°
  • basilar kyphosis: <125°
Modified MRI technique

This technique described by Koenigsbert et al. yields a normal value range (95% C.I) 116°-118° for adults and 113°-115° for children.

Angle formed by:

  1. line extending across the anterior cranial fossa to the tip to the dorsum sellae
  2. line drawn along the posterior margin of the clivus
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Article information

rID: 5241
Section: Gamuts
Synonyms or Alternate Spellings:
  • Basal angle
  • Measuring the skull base angle

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