Mamillopontine distance

Mamillopontine distance is defined as the distance between the inferior aspect of the mammillary bodies to superior aspect of the pons. In normal subjects, it should be >5.5 mm.

It is decreased in conditions such as
  • intracranial hypotension: it is one of the helpful quantitative signs helpful in improving the accuracy of MRI diagnosis
  • hydrocephalus: as one of the morphological changes at mid-sagittal MRI
Measurement method

The mamillopontine distance is measured on mid-sagittal T1WI MRI from the anterior root of the mamillary body to the top of the pons parallel to the anterior mesencephalon or the shortest distance between the center of the mammillary bodies and the upper surface of the pons. 

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Article information

rID: 43163
Section: Signs
Tags: stub, refs, cases
Synonyms or Alternate Spellings:
  • Mamillopontine distance

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Cases and figures

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    Case 1: normal
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    Case 2: reduced distanced due hydrocephalus
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