Hippocampal sulcus remnant cyst

Hippocampal sulcus remnant cysts, also known as hippocampal cavities, are remnants of incomplete involution of the embryonic hippocampal fissure and are an incidental finding.  

They are seen in ~25% (range 10-40%) of the adult population 1,3.

They consist of small (1-2 mm) cystic spaces that follow CSF on all sequences. They are located between the dentate gyrus and the cornu ammonis, at the lateral aspect of the hippocampal region, near the apex of the hippocampal fold 4.

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Article information

rID: 24971
Section: Anatomy
Synonyms or Alternate Spellings:
  • Hippocampal sulcal residual cavities
  • Hippocampal cavities
  • Hippocampal sulcus remnant

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Cases and figures

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