Agenesis of the Corpus Callosum
Description
There are a group of disorders of the corpus callosum. These are birth defects in
which there are problems with the connection between the left and the right side
of the brain (termed the corpus callosum).
- Agenesis: partial or complete absence of the corpus callosum
- Dysgenesis: malformation of the corpus callosum
- Hypogenesis: a partial formation of the corpus callosum
- Hypoplasia: underdevelopment of the corpus callosum
This can occur by itself or in combination with other brain formation problems or
syndromes.
Causes
For many children, we cannot identify a single cause. In these cases, there are
likely multiple. These factors may include genetics, metabolic disorders, and structural
interruptions.
Known causes of disorders of the corpus callosum include
- Chromosomal defects that affect fetal brain development
- Certain viral infections that a mother has while pregnant
- Exposure of the unborn baby to certain toxins (like alcohol) or medications
- Abnormal brain development caused by cysts
Diagnosis
Diagnosis is made by viewing the brain. This is with MRI, CT scan, or prenatal or
post-natal ultrasound.
Associated Developmental and Learning Issues
Children with disorders of the corpus callosum have a range of learning abilities
and disabilities. The level of difficulty depends on the number of brain structure
problems and the presence of other syndromes. Some children have mild learning problems.
Others have severe intellectual disabilities.
Other developmental skills and abilities often go along with cognitive abilities.
The more brain structure problems a child has, the more likely they are to have slow
development of speech, motor skills, and social skills. Some children who learn well
may have more “hidden” disabilities related to how they learn. For these children,
specialized evaluation of their learning strengths and weaknesses will be important
to support their success.
For children with primary disorders of the corpus callosum (without other syndromes
or brain formation problems), it is common to experience the following:
- Cognitive disabilities including learning problems through intellectual disabilities
- Problems with abstract thinking and problem solving
- Low muscle tone and poor motor coordination
- Attention Deficit Disorder
- Social immaturity
Associated Medical Conditions
Many children with Disorders of the corpus callosum have other health complications.
It is important that these are recognized and treated. A child with disorders of
the corpus callosum who is physically healthy is more likely to do well in school
and in other treatments. This contributes to more independence, better daily functioning,
and better quality of life. The type and severity of health problems is often dependent
upon whether the disorder of the corpus callosum is part of syndrome or something
that occurred by itself. If the child has a syndrome, it is important to understand
the health issues associated with that syndrome.
- Acrocallosal syndrome
- Aicardi syndrome
- Arnold-Chiari malformation
- Andermann syndrome
- Dandy-Walker syndrome
- Differences in the appearance of the face, including wide space between the eyes,
and hypertelorism (differences in appearance of the skin around the eyes)
- Fetal Alcohol syndrome
- Hearing problems
- Holoprosencephaly (failure of the forebrain to divide into lobe)
- Hydrocephalus
- Microcephaly (small head)
- Midline facial defects
- Poor muscle tone and coordination
- Schizencephaly (clefts or deep divisions in brain tissue)
- Seizures
- Shapiro syndrome
- Trisomy 13
- Trisomy 18
- Vision problems
Associated Behavioral Conditions
- ADHD
- Insomnia and other sleep problems