What is agenesis of the corpus callosum?

Agenesis of the corpus callosum (ACC) is a rare condition present from birth and affecting the brain. In this condition, the major nerve connections between the two sides (hemispheres) of the brain have not developed. These connections may be partially developed (partial agenesis), or completely absent (complete agenesis).

Usually, the cause of ACC is unknown. However, a minority of cases are caused by genetic mutations resulting in a wider genetic syndrome in the baby, or from injury during pregnancy such as certain infections.

A fetal medicine specialist doctor will perform an ultrasound scan of your baby in the womb to assess the brain and look for any associated abnormalities. You may be offered other tests such as MRI or amniocentesis. You may have the opportunity to talk with a paediatric neurologist – a specialist brain doctor looking after children with ACC after birth.

What is the outlook for a child with ACC?

The outlook for a child with ACC depends on the presence of other brain abnormalities, and the presence of a wider genetic condition.

Many children with isolated ACC (no other associated birth defects) have no symptoms. Other children develop various issues, including:

• Learning difficulties, including the possibility of needing to be enrolled in a special educational needs school
• Seizures
• Vision issues
• Problems with motor control and movement: such as problems with balance or hand-eye co-ordination, muscles that are too tight or too floppy
• Facial issues, and sometimes and head size that is large or small

What treatments are available for a child with ACC?

There is no cure for ACC. Treatment depends on disease severity. Children with mild cases may not require treatment. Children with more severe cases may need help from:

• Child neurologists, or brain specialists for children
• Developmental paediatricians, who can assess language, learning, behaviour, and development
• Other healthcare workers such as physiotherapy, speech and language therapy and occupational therapy

Where can I find more information?

CORPAL is a UK based charity and support group for people with agenesis of the corpus callosum