The lateral border was defined by a straight line from the most superolateral point of the collateral sulcus to the superior point of the mediotemporal cortex in the crural cistern.
In such cases it is necessary to enlarge the restrictive defect, usually at the expense of incision (or wedge-like resection) of the superolateral portion of the outlet septum.
The right (lateral) paracolic gutter runs from the superolateral aspect of the hepatic flexure of the colon, down the lateral aspect of the ascending colon, and around the caecum.
