Septo-optic dysplasia is a condition where a child is diagnosed with two or more of the following problems- optic nerve hypoplasia, midline brain abnormalities and pituitary gland abnormalities. It is a rare condition affecting around 1 in every 10,000 births, with boys and girls affected equally.
Septo-optic dysplasia is a congenital condition so it is present at birth, although it may not be diagnosed until childhood, or rarely, adolescence. Septo-optic dysplasia was formerly called de Morsier syndrome.
Causes of Septo-optic dysplasia
There is some evidence to suggest that septo-optic dysplasia is caused by a mutation or change, affecting one particular gene. However, in most cases, it is not thought to be an inherited disorder passed on from parent to child. It is highly unlikely to recur in further children within the family, and this suggests that the cause of the condition is complex.
Septo-optic dysplasia has commonly been seen in younger mothers, and environmental factors may play a role. There may have been a particular problem within the pregnancy, which is highly unlikely to recur in future pregnancies.
Signs and symptoms of Septo-optic dysplasia
Septo-optic dysplasia is diagnosed when two or more of the following problems are present, optic nerve hypoplasia, midline brain abnormalities and pituitary gland abnormalities. Only one-third of children diagnosed with septo-optic dysplasia will have all three features.
Treatment of Septo-optic dysplasia
- Optic nerve hypoplasia: This means that the optic nerve has not developed properly during pregnancy and remains small. In optic nerve hypoplasia, separate fibres present in the optic nerve have not developed properly. This can affect either one or both eyes and the effect on a child’s vision can vary greatly, although most children have a serious visual impairment.
- Midline brain abnormalities: Absence of small areas of the middle part of the brain called the septum pellucidum and corpus callosum may be associated with developmental delay. This means that a child will not reach their milestones of development at the expected age. For instance, they may walk later or their speech may be late.
- Pituitary gland abnormalities: The pituitary gland is located deep in the brain and is the master gland which produces many vital chemicals, called hormones. Most children with septo-optic dysplasia will have an abnormal pituitary gland causing low pituitary hormone levels and visual impairment. Developmental delay is also common, especially if the optic nerve hypoplasia is found to affect both eyes. Many children have sleep disturbances, autistic behaviours and a tendency to weight gain.
As septo-optic dysplasia affects a variety of body systems, a multidisciplinary approach involving different specialists is required to ensure that the best treatments are given. The team may include endocrinologists
(hormone specialists), ophthalmologists
(eye specialists) and neurologists
(brain specialists), as well as input from experts in visual impairment
and developmental delay. The basis of treatment is to identify which hormones are absent or not being produced properly, and replace these with man-made versions.
Support for visual impairment will enable your child to get the most out of school and social life as an additional help for development delay. Although septo-optic dysplasia is a genetic condition, it is extremely unusual for the affected gene to be identified in an individual at this stage. For this reason, genetic counselling is not usually helpful.