Interventricular foramen (of Monro)

The interventricular foramen, also known as foramen of Monro, is part of the ventricular system and the connection between the third ventricle and the lateral ventricles.

As it allows for the flow of cerebrospinal fluid between lateral ventricles and third ventricle, effacement or blockage causes reduction in CSF flow from the lateral ventricles. With normal continuation of CSF production in the choroid plexus this will lead to obstructive hydrocephalus.

The structure was named after the Scottish physician Alexander Monro (1733-1817), who first described it in 1783 3.

Anatomy: Brain
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Article information

rID: 5845
Section: Anatomy
Synonyms or Alternate Spellings:
  • Foramen of Monro
  • Interventricular foramen
  • interventricular foramina
  • foramina of Monro

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Cases and figures

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    Figure 1: lateral ventricles seem from above
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    Figure 2: ventricular system
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    Figure 3: ventricular system
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    Figure 4: coronal brain through 3rd ventricle
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    Case 1
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