collateral fissure

{{Short description|Brain structure}}

{{Infobox brain

| Name = Collateral fissure

| Latin = sulcus collateralis, fissura collateralis

| Image = Gray727 collateral fissure.svg

| Caption = Medial surface of left cerebral hemisphere. (Collateral fissure labeled at bottom left.)

| Image2 = OccCaptsMedial.png

| Caption2 = Medial surface of right cerebral hemisphere. Collateral sulcus divides limbic (purple) and temporal lobe (green).

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The collateral fissure is a large sulcus on the tentorial surface of the cerebral hemisphere and extends from near the occipital pole to within a short distance of the temporal pole. It is also known as the medial occipitotemporal sulcus.{{cite web |title=Occipitotemporal sulcus |url=https://radiopaedia.org/articles/occipitotemporal-sulcus?lang=gb |access-date=18 November 2024}}

Behind, it lies below and lateral to the calcarine fissure, from which it is separated by the lingual gyrus; in front, it is situated between the parahippocampal gyrus and the anterior part of the fusiform gyrus.