What is Absence of the Septum Pellucidum?

The septum pellucidum (SP) is a thin membrane located at the midline of the brain. Children who are born without this membraine and also have other abnormalities--pituitary deficiencies and abnormal development of the optic disk--have a disorder known as septo-optic dysplasia.

Is there any treatment?
Absence of the SP alone is not a disorder but is instead a characteristic noted in children with septo-optic dysplasia.

SO,What is Septo-Optic Dysplasia?

Septo-optic dysplasia (SOD) is a rare disorder characterized by abnormal development of the optic disk, pituitary deficiencies, and often agenesis (absence) of the septum pellucidum (the part of the brain that separates the anterior horns or the lateral ventricles of the brain). Symptoms may include blindness in one or both eyes, pupil dilation in response to light, nystagmus (a rapid, involuntary to-and-fro movement of the eyes), inward and outward deviation of the eyes, hypotonia , and hormonal problems. Seizures may also occur.
In a few cases, jaundice may occur at birth. Intellectual problems vary in severity among individuals. While some children with SOD have normal intelligence, others have learning disabilities and mental retardation. Most, however, are developmentally delayed due to vision impairment or neurological problems.

This Figure shows severity of classical triad of SOD
(i) optic nerve hypoplasia, (ii) pituitary hormone abnormalities and (iii) midline brain defects