Parieto-occipital fissure

The parieto-occipital fissure or sulcus, is an oblique sulcus which demarcates the occipital lobe from the parietal lobeon the medial surface of the cerebral hemisphere . The parieto-occipital sulcus joins the calcarine sulcus to form a pattern similar to the letter Y which has been placed sideways . Specifically, it delineates the precuneus superiorly from the cuneus inferiorly .

The lateral aspect of the sulcus marks the superior margin of the imaginary lateral parietotemporal line, a near vertical line drawn superiorly from the preoccipital notch, to demarcate the temporal lobe anteriorly from the occipital lobe posteriorly.