Meningomyelocele

What is Meningomyelocele?

Meningomyelocele, also known as open spina bifida, is a severe birth defect that affects the central nervous system and can cause serious health problems and even death. This condition comes under a group of birth defects called neural tube defects which can be of two kinds:

* Open neural tube defect: This is when the defect is either completely open or only covered by a thin layer of skin. It is the most common type, making up about 80% of all neural tube defects.
* Closed neural tube defect: This is a type where there are no visible defects externally. It usually involves a problem in the fat, bone, or membranes covering the spinal cord.

The most commonly occurring open neural tube defect is called myelomeningocele. This happens when the neural tube, which is a part of the developing embryo, does not close correctly in the lower spinal area (referred to as the lumbosacral region). This usually happens around the fourth week after fertilization, resulting in a condition where the protective coverings of the spinal cord (the meninges) and the spinal cord itself stick out through a gap in the spine.

Normally, the neural tube closes up from the brain level and extends towards the top (rostrally) and bottom (caudally) of the embryo. If this closing process does not take place correctly at the bottom end, meningomyelocele birth defect will occur around the 26th day of gestation.

What Causes Meningomyelocele?

Neural tube defects, which are birth defects of the brain, spine, or spinal cord, usually happen on their own without any clear reason. But, there are several things that can increase the risk of a baby developing one of these defects:

1. Genetics and chromosome issues: The risk increases if a parent or sibling has a neural tube defect. Certain genetic conditions like Trisomies 18 and 13, Meckel-Gruber syndrome, Roberts syndrome, Jarcho-Levin syndrome (which affects the spine and ribs and is more common in Puerto Ricans) and HARD syndrome, along with several others also increase the risk.

2. Problems with the amniotic bands: Normally, the baby develops in a sac filled with fluid known as the amniotic sac. Sometimes, strands from this sac, called amniotic bands, can keep the baby’s nervous system from developing correctly.

3. The mother’s environment and what she’s exposed to: This includes drinking alcohol, having a lot of caffeine, smoking, exposure to air pollution, harmful substances in drinking water like disinfectant byproducts, and chemicals found in things like cleaning solutions, pesticides, and certain foods. Also, exposure to high heat like hot tubs and saunas in early pregnancy may cause a neural tube defect in the baby.

4. The mother’s health: Moms who have high blood sugar levels, gestational diabetes (which is a diabetes type that some women get during pregnancy), certain infections, obesity, and stress may have a higher risk of having a baby with a neural tube defect.

5. Nutrition: Moms who don’t get enough of certain nutrients like folate, methionine, zinc, vitamin C, vitamin B12, and choline are at a higher risk.

6. Certain Medications: Medications that interfere with the body’s use of folic acid like valproic acid, carbamazepine, and methotrexate, increase the risk. As folic acid is critical in the development of the nervous system, not having enough of it in early pregnancy can cause neural tube defects.

Risk Factors and Frequency for Meningomyelocele

Myelomeningocele is a common birth disorder. In the United States, it affects roughly 0.2 to 0.4 out of 1,000 newborns. This condition affects more people in the Latino community and is several times more common in certain regions of China, parts of Africa, the Middle East, Thailand, and India. Dietary guidelines regarding folate supplements in these countries may be a contributing factor to the higher incidence rates.

Myelomeningocele is a typical birth disorder.
It affects about 0.2 to 0.4 out of 1,000 newborns in the United States.
The Latino population has a higher incidence rate.
Females are 3-7 times more likely to have this condition than males.
The condition is also more common in certain regions of China, parts of Africa, the Middle East, Thailand, and India.
Dietary guidelines about folate supplements may explain the regional differences.
The condition is more common among people with lower socioeconomic status and older mothers.
For people who’ve had a child with this condition, there’s a 2-3% chance of it happening again in future pregnancies.

Signs and Symptoms of Meningomyelocele

It’s usually easy to diagnose a newborn with myelomeningocele (a form of spina bifida), as there’s a noticeable sac containing different things like spinal fluid and nerve tissue that can be seen sticking out the back. If a newborn has this condition, what they experience can depend on:

Where the sac is located
Whether they also have a condition called hydrocephalus
Whether there are also abnormalities in the brain

Sometimes, a newborn with this condition might not show any symptoms for up to 6 weeks. If they also have hydrocephalus, they may show signs of increased pressure in the brain, such as a growing head size, irritability, sleepiness, and difficulty looking upwards.

Many people with spina bifida have issues with feeling and moving below where the sac is (about 97% have issues with bowel and bladder function). Problems with walking are common due to muscle weakness and usually get worse over time. In severe cases, individuals might not be able to move or feel anything at all below the sac.

Spina bifida can also come with a brain malformation called a Chiari-II malformation, where parts of the brain are moved downwards. This can block the flow of spinal fluid, leading to hydrocephalus. This and other brain abnormalities can cause serious issues. If the brainstem isn’t working properly, individuals could have trouble swallowing and weak vocal cords, which could lead to difficulties breathing.

Testing for Meningomyelocele

Most newborn babies with spina bifida are identified before they are born through a mother’s ultrasound or a blood test that checks for a protein known as alpha-fetoprotein. A high-quality ultrasound during the second trimester of pregnancy is the preferred method for spotting these types of issues as it tends to be more precise in finding neural tube defects than the alpha-fetoprotein blood test.

If the screening tests show potential signs of spina bifida, more in-depth tests will need to be done. These include a complete anatomy scan, genetic tests like fetal karyotype (which looks at the structure and number of chromosomes), and sometimes a fetal magnetic resonance imaging (MRI) test if the ultrasound results aren’t clear.

Once spina bifida is confirmed, it’s important for the healthcare team to provide thorough counseling to the parents. This would involve discussing the typical progression of spina bifida, offering more prenatal tests if desired, and discussing different management options. These choices may include ending the pregnancy, surgery after birth, or in some cases, surgery on the baby while still in the womb if it’s available and suitable.

Regular ultrasounds are also conducted to keep an eye on the baby’s head growth and the size of the brain’s ventricles (fluid-filled spaces), as well as to assist with planning the baby’s delivery.

Treatment Options for Meningomyelocele

Surgery performed on a baby while still in the womb is increasingly being used to treat a birth defect called myelomeningocele. Research on animals has shown that closing the myelomeningocele defect before birth can protect the baby’s growing nerves from damage caused by exposure to amniotic fluid, which is the fluid that surrounds the baby in the womb.

In a study that compared surgery before birth (known as prenatal surgery) to surgery after birth (postnatal surgery), the results were so good with prenatal surgery that the study was stopped early. The study showed that babies who had surgery before birth were less likely to need a device called a shunt to remove excess fluid from the brain (40% needed it in the prenatal group compared to 82% in the postnatal group). It also found that children who had surgery before birth showed better mental progress and motor skills at 30 months old. However, there were some risks with prenatal surgery, such as a higher chance of delivering the baby early, and a risk of uterine rupture at the time of delivery.

Once the infant is born, medical professionals must carefully examine the defect while the infant is laid on their side or stomach. Non-latex gloves are used to help avoid a latex allergy. A moist dressing or plastic wrap is used to cover the defect to keep the baby warm. If surgery is performed after birth, it’s usually done as soon as possible (ideally within the first two days) to limit the risk of infection.

Some babies with myelomeningocele also have a brain condition called a Chiari II malformation, which can cause problems with the brainstem. In these cases, an extra surgical procedure might be done to relieve pressure on the brainstem and the lower part of the brain called the cerebellum.

Children with this condition often benefit from a team approach involving different healthcare specialties. If the child has problems with urine retention, healthcare providers may perform daily catheterization, a procedure that empties the bladder to decrease the chances of urinary tract infections. The child might also need to see an orthopedic specialist for bone-related complications such as contractures (permanent shortening of a muscle or tendon) and scoliosis (curvature of the spine).

Deliveries should ideally be done in a hospital with a well-equipped neonatal intensive care unit and pediatric neurosurgery services. To avoid complications related to prematurity, delivery should occur at full term. If surgery is done while the baby is still in the womb, doctors recommend a cesarean section at 37 weeks or earlier if there’s a maternal indication, to minimize the chances of the uterus rupturing.

When diagnosing neural tube defects, doctors must rule out the following potential conditions:

Caudal regression syndrome (sacral agenesis)
Sacrococcygeal teratoma
Multiple vertebral segmentation disorder
VACTERL (vertebral anomalies, anal atresia, cardiac abnormalities, tracheoesophageal atresia/esophageal atresia, renal anomalies, and limb defect)
Spine segmental dysgenesis

What to expect with Meningomyelocele

Patients with spina bifida, a condition where the spine and spinal cord don’t form properly, have a death rate of about 1% each year from age 5 to 30. If the defect is located higher on the spine, the risk of complications and mortality are also higher. These defects severely affect the quality of life for survivors.

It is common for those living with spina bifida to struggle with emotional and mental health issues, like depression and anxiety. They may also tend to engage in more risk-taking behaviors. Research shows that they are most likely to face challenges in areas such as getting a job, having romantic relationships, and achieving financial independence.

Possible Complications When Diagnosed with Meningomyelocele

People with myelomeningocele, a type of birth defect where an infant’s spine doesn’t develop properly, can face various complications. These include:

Struggling with learning disabilities and cognitive impairments, which might affect their mental abilities.
Experiencing seizures, which are sudden, uncontrolled disturbances in the brain.
Suffering from paralysis and a lack of feeling in parts of the body below the site of the spinal defect.
Having limited movement due to the associated muscle weakness.
Dealing with a ‘neurogenic bladder,’ which could lead to frequent urinary tract infections.
Experiencing bowel dysfunction.
Developing pressure ulcers (sores) due to a loss of sensation.
Facing orthopedic issues related to paralysis, such as scoliosis (a sideways curve of the spine), contractures (permanent tightening of muscles), hip dislocation, and others.

Preventing Meningomyelocele

Spina bifida is a birth defect where the spinal cord doesn’t form the way it should while a baby is developing in the mother’s womb. This condition is also known as myelomeningocele or open neural tube defect. As a result, there may be an opening in the baby’s back, through which some parts of the spine and nerve tissue can stick out.

These types of defects can result in a variety of long-term troubles for your child, and the severity of these troubles depends on how severe the defect is. Here are some difficulties children with spina bifida might face:

Weak legs, making walking difficult or impossible
Lack of feeling below their waist
Difficulty controlling urine and feces
Learning or memory problems
Some children may also have too much fluid in their brain, requiring surgery to relieve brain pressure

If you learn that your baby has spina bifida before they are born, some parents consider ending the pregnancy, while others choose to continue. If you choose to continue the pregnancy, some medical centers can perform surgery on your baby while it’s still in the womb to correct the defect, or they can do surgery just after the baby is born. After this initial treatment, your child will need ongoing care throughout their life.

Depending on the severity, your child may need:

A wheelchair or assistive devices to help them walk
Additional surgeries to address issues with their bones
Additional testing and support at school if they have learning difficulties
If their bladder doesn’t function correctly, they may need a tube to help empty their bladder

This condition will impact your child’s life. The best way to support your child will be to ensure they are cared for by a team of medical experts who are experienced in treating patients with this condition.

Frequently asked questions

Meningomyelocele is a severe birth defect that affects the central nervous system and occurs when the protective coverings of the spinal cord and the spinal cord itself protrude through a gap in the spine.

Myelomeningocele affects roughly 0.2 to 0.4 out of 1,000 newborns in the United States.

Signs and symptoms of Meningomyelocele (a form of spina bifida) can vary depending on several factors. However, some common signs and symptoms include: - Noticeable sac containing spinal fluid and nerve tissue sticking out of the back - Increased head size in newborns with hydrocephalus - Irritability and sleepiness in newborns with hydrocephalus - Difficulty looking upwards in newborns with hydrocephalus - Issues with feeling and moving below the location of the sac - Problems with bowel and bladder function in about 97% of cases - Muscle weakness leading to difficulties with walking - Progressive worsening of walking difficulties over time - In severe cases, complete loss of movement and sensation below the sac - Chiari-II malformation, a brain malformation that can accompany spina bifida, leading to additional symptoms such as: - Blockage of spinal fluid flow, causing hydrocephalus - Trouble swallowing due to improper functioning of the brainstem - Weak vocal cords, which can result in difficulties breathing It's important to note that the signs and symptoms can vary from person to person, and the severity of the condition can also vary. It is recommended to consult with a healthcare professional for a proper diagnosis and individualized treatment plan.

Meningomyelocele, also known as myelomeningocele, is typically a birth defect that occurs when the neural tube, which forms the brain, spine, and spinal cord, does not close properly during fetal development.

Caudal regression syndrome (sacral agenesis), Sacrococcygeal teratoma, Multiple vertebral segmentation disorder, VACTERL (vertebral anomalies, anal atresia, cardiac abnormalities, tracheoesophageal atresia/esophageal atresia, renal anomalies, and limb defect), Spine segmental dysgenesis.

The types of tests needed for Meningomyelocele include: - High-quality ultrasound during the second trimester of pregnancy - Alpha-fetoprotein blood test - Complete anatomy scan - Fetal karyotype (genetic test) - Fetal magnetic resonance imaging (MRI) test - Regular ultrasounds to monitor head growth and brain ventricles - Examination of the defect after birth - Non-latex gloves to avoid latex allergy - Surgical procedures to relieve pressure on the brainstem and cerebellum if necessary - Catheterization for urine retention - Consultation with an orthopedic specialist for bone-related complications - Delivery in a hospital with a well-equipped neonatal intensive care unit and pediatric neurosurgery services - Cesarean section at 37 weeks or earlier if necessary to minimize the risk of uterine rupture.

Meningomyelocele is treated through surgery, which can be performed either before or after birth. Surgery performed before birth, known as prenatal surgery, has shown to be more effective in protecting the baby's growing nerves from damage caused by exposure to amniotic fluid. In a study comparing prenatal surgery to postnatal surgery, it was found that babies who had surgery before birth were less likely to need a shunt to remove excess fluid from the brain. They also showed better mental progress and motor skills at 30 months old. However, prenatal surgery carries risks such as a higher chance of delivering the baby early and a risk of uterine rupture at the time of delivery. If surgery is performed after birth, it is usually done as soon as possible to limit the risk of infection. Additionally, some babies with meningomyelocele may require an extra surgical procedure to relieve pressure on the brainstem and the lower part of the brain. A team approach involving different healthcare specialties is often necessary for the comprehensive care of children with this condition.

The side effects when treating Meningomyelocele include: - Higher chance of delivering the baby early - Risk of uterine rupture at the time of delivery - Struggling with learning disabilities and cognitive impairments - Experiencing seizures - Suffering from paralysis and a lack of feeling in parts of the body below the site of the spinal defect - Having limited movement due to associated muscle weakness - Dealing with a 'neurogenic bladder,' which could lead to frequent urinary tract infections - Experiencing bowel dysfunction - Developing pressure ulcers (sores) due to a loss of sensation - Facing orthopedic issues related to paralysis, such as scoliosis, contractures, hip dislocation, and others.

The prognosis for Meningomyelocele can vary depending on the severity of the condition and the individual's overall health. However, it is generally considered a severe birth defect that can cause serious health problems and even death. Patients with Meningomyelocele may have a higher risk of complications and mortality, and the condition can severely affect their quality of life.

A pediatric neurosurgeon.

Child Health Congenital Disorders Neural Tube Defects