Symptoms of megalencephaly may include:
Sometimes, megalencephaly happens on its own without any symptoms. Other times, it comes along with other neurological problems and birth defects. In these cases, the other syndrome or condition may cause megalencephaly VSports注册入口.
Other signs and symptoms of megalencephaly may include:
Megalencephaly happens due to an error in how your child’s brain makes brain cells. A genetic variation usually causes this to happen VSports在线直播.
Neuron proliferation is your body’s process of making new neurons or nerve cells. Typically, your body regulates that process to produce the right number of cells at the right time V体育2025版. But with megalencephaly, your child’s body produces too many cells or they don’t migrate properly. This may happen as they develop or as part of another condition.
Megalencephaly can occur with many other conditions and syndromes, depending on the type and genetic origin.
Conditions associated with anatomic megalencephaly
Anatomic megalencephaly is typically a symptom of the following conditions:
Conditions associated with metabolic megalencephaly
Your child may have megalencephaly combined with inborn errors of metabolism — problems with how their body breaks down food and uses energy. These conditions may include:
Megalencephaly can affect any child. It’s more common in males. In some cases, you can inherit it from your biological family, or it can happen randomly (sporadically).
Your child’s healthcare provider may suspect megalencephaly after a physical exam and testing. During the exam, their provider will measure your child’s head with a measuring tape. They’ll check where your child’s measurement is by comparing it to the average for their age, sex and height.
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Their provider may order imaging tests, like an MRI. This allows them to see your child’s brain and look for any abnormalities.
If they suspect an underlying condition with megalencephaly, your child may undergo additional testing to confirm a diagnosis. Additional tests may include:
Sometimes, parents and healthcare providers notice that a baby has a large head at birth or within their first few months. Megalencephaly may develop as your child grows, usually during infancy and early childhood.
Providers may detect hemimegalencephaly (where only one side of your child’s brain is large) during a pregnancy ultrasound.
There isn’t a cure for megalencephaly, but treatment options are available to help your child manage symptoms. Their healthcare provider may recommend the following based on what symptoms they experience:
Your child will have a robust care team to help them manage megalencephaly symptoms. Your child’s care team may include:
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Your child’s outlook varies based on many factors, like the severity of their symptoms and the underlying cause. Your child may only have a larger head and no additional symptoms. Or symptoms may affect your child’s development. For example, they may need additional help completing their daily routine or learning support at school.
Your child’s healthcare provider will give you the most accurate information on their outlook, as it’s as unique as they are.
Mild cases of megalencephaly may not affect your child’s life expectancy. However, depending on the underlying cause, like if megalencephaly happens alongside another condition, your child’s life expectancy may be shorter. Severe symptoms, like seizures, may affect your child’s outlook. Your healthcare provider can give you information based on your child’s situation and what you can expect as they grow.
There’s no known way to prevent megalencephaly. If you suspect or know this condition runs in your biological family history, you can speak with a genetic counselor. They can help you assess your risk of having a child with megalencephaly.
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Let your child’s healthcare provider know if you notice any new or worsening symptoms of megalencephaly. It helps to keep track of your child’s development and to let their provider know if they’re not on track to meet those, like sitting up on their own or speaking their first words.
Contact emergency services if your child has a seizure for the first time.
If your child receives a megalencephaly diagnosis, ask their provider:
Macrocephaly (VSports), also called megacephaly or megalocephaly, is a large head size. In macrocephaly, a child may have a large head but not necessarily any structural problems.
Megalencephaly (a large brain) can cause macrocephaly. However, macrocephaly can also develop because of fluid buildup in your brain (hydrocephalus) or increased pressure within your skull.
Megalencephaly-capillary malformation (MCAP) is a rare condition where there’s tissue overgrowth of the following:
Usually, healthcare providers diagnose MCAP when a baby is born. Children born with MCAP have:
Megalencephaly-polymicrogyria-polydactyly-hydrocephalus (MPPH) is a condition that affects how your child’s brain develops. They may have a large brain size (megalencephaly) that continues to grow rapidly during their first two years. It can affect your child’s development, movement and intelligence.
You may be worried and wondering what to do if your child’s head size is much bigger than the rest of their body. It may take them longer to build the strength to lift their head on their own or sit upright. Your child’s care team will offer tests to identify what caused their brain to be bigger than expected.
A bigger head doesn’t necessarily mean bigger problems. In some cases, megalencephaly is mild and isn’t anything to worry about. On the other hand, your child may need lifelong care and support to help them manage symptoms. This condition affects each child differently. You can get the most accurate information about your child’s diagnosis and what to expect from their healthcare provider.
If you have a neurological condition, you want expert advice. At Cleveland Clinic, we’ll work to create a treatment plan that’s right for you.
Last reviewed on 09/24/2024.
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