Absence of the septum pellucidum (ASP) is a rare condition in which the thin membrane in the middle of the brain is missing. ASP can be a feature of certain developmental conditions, such as septo ...

One dog with supracollicular fluid accumulation also had absent septum pellucidum. Five of the six dogs with supracollicular fluid accumulation and the dog with fourth ventricle arachnoid diverticulum ...