Septo-optic dysplasia (SOD) is a rare disorder characterized by abnormal embryological development of the optic disk, pituitary deficiencies, and often absence of the septum pellucidum (a midline part of the brain). It is also known as de Morsier syndrome.

Septo-optic dysplasia is linked to young maternal age. One third of Septo-optic births are the result of teenage pregnancies. The cause of septo-optic dysplasia is not known. Rare familial recurrence has been reported, suggesting at least one genetic form.

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 (low muscle tone)
• Hormonal problems
• Seizures
• In a few cases, jaundice (prolonged yellow skin discoloration) 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.

The prognosis for individuals with SOD varies according to the presence and severity of symptoms.

Treatment for SOD is symptomatic. Hormone deficiencies may be treated with hormone replacement therapy. The optical problems associated with SOD are generally not treatable. Vision, physical, and occupational therapies may be required.