Spina bifida is a birth defect in which there is spinal closure and an incomplete membrane around the spinal cord. There are three main types: spina bifida occulta â € , meningocele , and myelomeningocele . The most common location is the lower back, but in rare cases it may be the middle back or neck. Occulta does not have or only mild signs. Occult signs may include hairy patches, dimples, dark spots, or swelling on the back at the site of the spine in the spine. Meningocele usually causes mild problems with fluid sacs present in the cracks in the spine. Myelomeningocele, also known as open spina bifida, is the most severe form. Related problems include poor walking ability, problems with bladder or bowel control, hydrocephalus, delayed spinal cord, and latex allergies. Learning problems are relatively rare.
Spina bifida is believed to be due to a combination of genetic and environmental factors. After having one child with the condition or if one of the parents has the condition, there is a 4% chance that the next child will also be affected. Not having enough folate in the food before and during pregnancy also plays an important role. Other risk factors include certain antiseizure medications, obesity, and diabetes that are not well controlled. Diagnosis can occur either before or after a child is born. Before birth if blood tests or amniocentesis find a high alpha-fetoprotein level (AFP), there is a higher risk of spina bifida. Ultrasound examination can also detect problems. Medical imaging can confirm the diagnosis after birth. This is a type of neural tube defect with other types including anencephaly and encephalocele.
Most cases of spina bifida can be prevented if the mother gets enough folate before and during pregnancy. Adding folic acid to the flour is found to be effective for most women. Open spina bifida can be closed surgically before or after birth. A shunt may be required in those with hydrocephalus, and the tethered spinal cord can be repaired surgically. Devices to aid movements such as crutches or wheelchairs may be useful. Urine catheterization may also be needed.
About 15% of people have spina bifida occulta. Other rates of spina bifida vary significantly by country, from 0.1 to 5 per 1,000 births. The average in developed countries occurs at about 0.4 per 1,000 births. In the United States, it affects about 0.4 per 1,000 births, and in India, about 1.9 per 1,000 births. Part of this difference is believed to be race - with Caucasians at high risk - and partly because of environmental factors. The term is Latin for "split spine".
Video Spina bifida
Type
There are two types: spina bifida occulta and spina bifida cystica. Spina bifida cystica can then be broken down into meningocele and myelomeningocele.
Spina bifida occulta
Occulta is Latin for "hidden". This is the lightest form of spina bifida. In the occult, the exterior of some vertebrae is not completely closed. The split in the vertebra is so small that the spinal cord is not prominent. The skin at the site of the lesion may be normal, or there may be some hair growing from it; there may be a dimple on the skin, or a birthmark. Unlike most other types of neural tube defects, spina bifida occulta is not associated with an increase in AFP, a common screening tool used to detect neural tube defects in the uterus. This is because, unlike most other neural tube defects, the dural layer is maintained.
Many people with this type of spina bifida do not even know they have it, because the condition is asymptomatic in most cases. About 15% of people have spina bifida occulta, and most people are accidentally diagnosed from spinal X-rays. A systematic review of radiographic studies found no association between spina bifida occulta and back pain. More recent studies not included in the review support negative findings.
However, other studies have shown that spina bifida occulta is not always harmless. One study found that among patients with back pain, severity was worse if spina bifida occulta was present. Among women, this can be misinterpreted as dysmenorrhea.
Incomplete posterior fusion is not a true spina bifida, and very rarely has neurological significance.
Meningocele
Meningocele posterior ( ) or meningeal cyst ( ) is the most uncommon form of spina bifida. In this form, a single developmental defect allows meninges for herniation between the vertebrae. When the nervous system remains undamaged, individuals with meningocele may not suffer long-term health problems, even though a cord case has been reported. Causes of meningocele include teratomas and other tumors of sacrococcyx and presacral space, and Currarino syndrome.
Meningocele can also be formed through dehiscences at the base of the skull. These can be classified by their localization for occipital, frontoethmoidal, or nose. Endonasal meningoceles are located on the roof of the nasal cavity and may be mistaken for nasal polyps. They are treated surgically. Encephalomeningoceles are classified in the same way and also contain brain tissue.
Myelomeningocele
Myelomeningocele, also known as meningomyelocele, is a type of spina bifida that often produces the most severe complications. In individuals with myelomeningocele, the unused spine allows the spinal cord to protrude through the opening. The meningeal membrane covering the spinal cord also protrudes through the opening, forming a pouch that lines the spinal elements, such as the meninges, cerebrospinal fluid, and parts of the spinal cord and nerve roots.
Myelocele
Spina bifida with Myelocele is the most severe form of myelomeningocele. In this type, the enclosed area is represented by a flat, plate-shaped neutral mass without a membrane over it. These nerve and tissue exposures make babies more susceptible to life-threatening infections such as meningitis.
The prominent part of the spinal cord and the nerves originating at the level of the rope are damaged or are not well developed. As a result, there is usually some degree of paralysis and loss of sensation below the level of spinal cord defects. Thus, the more the rate of defects, the more severe the associated nerve dysfunction and can cause paralysis. Symptoms may include ambulatory problems, loss of sensation, hip, knee or leg abnormalities, and loss of muscle tone.
Maps Spina bifida
Signs and symptoms
Physical problems
The physical signs of spina bifida may include:
- Weakness and leg paralysis
- Orthopedic disorders (ie, club legs, hip dislocations, scoliosis)
- Bladder and intestinal control issues, including incontinence, urinary tract infections, and poor kidney function
- Pressure and skin irritation
- Abnormal eye movements
68% of children with spina bifida have allergies to latex, ranging from mild to life-threatening. The use of latex that is common in medical facilities makes this a serious concern. The most common approach to avoid developing allergies is to avoid contact with latex-containing products such as examination gloves and condoms and catheters that do not specify them latex free, and many other products, such as some commonly used by dentists.
Spinal cord lesions or surgical scarring can cause spinal cord that is moored. In some individuals, this leads to significant traction and stress on the spinal cord and may lead to worsening of related paralysis, scoliosis, back pain, and worsening bowel and/or bladder function.
Neurological issues
Many individuals with spina bifida have cerebellar related abnormalities, called the Arnold Chiari II malformations. In affected individuals, the back of the brain is removed from the back of the skull to the upper neck. About 90% of people with myelomeningocele, hydrocephalus also occur because the replaced cerebellum interferes with the normal flow of cerebrospinal fluid, causing excess fluid to accumulate. In fact, the cerebellum also tends to be smaller in individuals with spina bifida, especially for those with higher rates of lesions.
The corpus callosum abnormally develops in 70-90% of individuals with myelomeningocele spina bifida; this affects the communication process between the left and right hemispheres. Furthermore, the white substance that connects the posterior brain region with the anterior area appears less organized. The white matter channel between the frontal areas has also been found to be disrupted.
Cortex abnormalities can also be present. For example, the frontal regions of the brain tend to be thicker than expected, while the posterior and parietal regions are thinner. The thinner part of the brain is also associated with increased cortical folds. Neurons in the cortex can also evacuate.
Executive function
Several studies have demonstrated difficulties with executive function in youth with spina bifida, with larger deficits observed in children with mashed hydrocephalus. Unlike specially developed children, young people with spina bifida do not tend to increase in their executive function as they grow older. Special areas of difficulty in some individuals include planning, organizing, initiation, and working memory. Problem-solving, abstraction, and visual planning can also be disrupted. Furthermore, children with spina bifida may have poor cognitive flexibility. Although executive function is often associated with the frontal lobe of the brain, individuals with spina bifida have an intact frontal lobe; therefore, other areas of the brain can be implicated.
Individuals with spina bifida, especially those with the shortest hydrocephalus, often have attention problems. Children with spina bifida and shunted hydrocephalus had higher levels of ADHD than children without the condition (31% vs. 17%). The deficit has been observed for selective attention and focused attention, although poor motor speed can contribute to poor scores on attention tests. The attention deficit may appear at a very early age, as infants with spina bifida lag behind their peers in the orientation of the face.
Academic skills
Individuals with spina bifida can struggle academically, especially in math and reading subjects. In one study, 60% of children with spina bifida were diagnosed with learning disabilities. In addition to brain disorders that are directly related to a variety of academic skills, achievement is likely influenced by attention control disorders and executive function. Children with spina bifida can work well in elementary school, but start struggling because of increasing academic demands.
Children with spina bifida are more likely than their peers without spina bifida to be dyscalculic. Individuals with spina bifida have demonstrated stable difficulties with arithmetic accuracy and speed, mathematical problem solving, and common usage and understanding of numbers in everyday life. Mathematical difficulty may be directly related to the depletion of the parietal lobe (the area involved in mathematical functions) and indirectly associated with small brain and midbrain deformities that affect other functions involved in math skills. Furthermore, the higher number of shunt revisions is associated with poorer math skills. Working memory and inadequate control of inhibition have been implicated for mathematical difficulties, although visual-spatial difficulties may not be involved. Early intervention to address the mathematical difficulties and associated executive functions is essential.
Individuals with spina bifida tend to have better reading ability than math skills. Children and adults with spina bifida have a stronger ability to read accuracy than in reading comprehension. Understanding may be very disturbed for texts that require abstract synthesis of information rather than a more literal understanding. Individuals with spina bifida may have difficulty with writing because of deficits in fine motor control and working memory.
Cause
Spina bifida is believed to be caused by a combination of genetic and environmental factors. After having one child with the condition, or if the parent has the condition, there is a 4% chance the next child will also be affected. Lack of folic acid during pregnancy also plays an important role. Other risk factors include certain antiseizure medications, obesity, and poorly managed diabetes. Drinking alcohol often triggers macrocytosis that removes folate. After stopping drinking alcohol, it takes several months to rejuvenate the bone marrow and recover from macrocytosis.
Those who are white or Hispanic have a higher risk. More vulnerable girls are born with spina bifida.
Pathophysiology
Spina bifida is sometimes caused by a failure of a neural tube to close during the first month of embryo development (often before the mother knows she is pregnant). Several forms are known to occur with primary conditions leading to increased central nervous system pressure, increasing the likelihood of multiple pathogenesis.
Under normal circumstances, neural tube closure occurs approximately 23 (rostral closure) and 27 (caudal closure) days after conception. However, if something interferes and the tube fails to close properly, neural tube defects will occur. Drugs such as some anticonvulsants, diabetes, obesity, and having relatives with spina bifida may affect the possibility of neural tube malformations.
The broad evidence of a strain mouse with spina bifida shows that there is sometimes a genetic basis for the condition. Human spina bifida, like other human diseases, such as cancer, hypertension and atherosclerosis (coronary artery disease), is likely to result from the interaction of multiple genes and environmental factors.
Studies have shown that the lack of folic acid (folate) is a contributing factor in the pathogenesis of neural tube defects, including spina bifida. Fetal maternal diet supplementation may reduce the incidence of neural tube defects by about 70%, and may also decrease the severity of this defect when it occurs. It is unknown how or why folic acid has this effect.
Spina bifida does not follow direct hereditary patterns such as muscular dystrophy or hemophilia. Studies show a woman has had one child with neural tube defects such as spina bifida having about 3% risk of having another child affected. This risk can be reduced by folic acid supplementation before pregnancy. For the general population, low-dose folic acid supplements are recommended (0.4 mg/day).
Prevention
There is no single cause of spina bifida or known way to prevent it altogether. However, diet supplementation with folic acid has been shown to be useful in reducing the incidence of spina bifida. Sources of folic acid include whole grains, fortified breakfast cereals, dried beans, leafy vegetables and fruits.
Fortified fortified grain folate products have been mandatory in the United States since 1998. The US Food and Drug Administration, the Canadian and British Public Health Agency recommends the amount of folic acid for women of childbearing age and women planning to become pregnant at least 0.4 Ã, mg/day of folic acid from at least three months before conception, and continued for the first 12 weeks of pregnancy. Women who have had babies with spina bifida or other types of neural tube defects, or taking anticonvulsant drugs, should take a high dose of 4-5 mg/day.
Certain mutations in the VANGL1 gene have been associated with spina bifida in some families with a history of the condition.
Screening
Open spina bifida can usually be detected during pregnancy with fetal ultrasound. Increased maternal serum alpha-fetoprotein levels (MSAFP) should be followed by two tests - fetal spine ultrasound and amniotic amniotic fluid of the mother (to test alpha-fetoprotein and acetylcholinesterase). The AFP test is now mandated by several state laws (including California). and failure to provide them can have legal consequences. In one case, a man born with spina bifida was awarded a $ 2 million settlement after the court found OBGYN negligent for not performing this test. Spina bifida may be associated with other malformations such as dysmorphic syndrome, often leading to spontaneous abortion. In most cases, spina bifida is an isolated malformation.
Genetic counseling and further genetic testing, such as amniocentesis, may be offered during pregnancy, as some neural tube defects are associated with genetic disorders such as trisomy 18. Ultrasound examination for spina bifida is partly responsible for the reduction of new cases, as many pregnancies are terminated for fear that infants Newborns may have a poor quality of life in the future. With modern medical care, the quality of life of patients is greatly improved.
Treatment
There is no known cure for nerve damage caused by spina bifida. Standard treatment is postpartum surgery. This operation aims to prevent further damage of the neural network and prevent infection; pediatric neurosurgeons operate to close the opening at the back. The spinal cord and its nerve roots are inserted back into the spine and covered with meninges. In addition, the shunt can be operated surgically to provide a continuous drain for the excess of cerebrospinal fluid produced in the brain, as is the case with hydrocephalus. Shunts most often flow into the abdomen or chest wall.
Pregnancy
The standard treatment is after delivery. There is tentative evidence about treatment for severe disease before delivery when the baby is in the uterus. In 2014 evidence; However, still not enough to determine the benefits and dangers.
Spina bifida treatment during pregnancy is not without risk. For the mother, this includes uterine scarring. For infants, there is a risk of premature birth.
Broadly speaking, there are two forms of prenatal care. The first is open fetal surgery, where the uterus is opened and spina bifida repair is performed. The second is through fetoscopy. These techniques can be an option for standard therapy.
Childhood
Most individuals with myelomeningocele will require periodic evaluations by various specialists:
- Physiatris coordinates the rehabilitation efforts of various therapists and prescribes specific therapy, adaptive equipment, or medications to encourage high functional performance within the community.
- Orthopedic experts monitor the growth and development of bone, muscle, and joints.
- Neurosurgeons perform surgery at birth and manage complications associated with tethered straps and hydrocephalus.
- Neurologists treat and evaluate problems of the nervous system, such as seizure disorders.
- Urologists to treat kidney, bladder, and gut dysfunction - many need to manage their urinary system with catheterization programs. Intestinal management programs aimed at improving elimination are also designed.
- Ophthalmologists evaluate and treat eye complications.
- Design orthotists and customize different types of auxiliary technologies, including braces, crutches, pedestrians, and wheelchairs to assist mobility. As a general rule, the higher the level of spina bifida defects, the more severe the paralysis, but paralysis is not always the case. Thus, those with low levels may only need a short leg buffer, while those with higher levels are best equipped with wheelchairs, and some may walk without help.
- Physical therapists, occupational therapists, psychologists, and speech/linguistic pathologists assist in rehabilitation therapy and improve self-care skills.
Transition to maturity
Although many child hospitals have an integrated multidisciplinary team to coordinate adolescent health care with spina bifida, the transition to adult health care can be difficult because the above health care professionals operate independently of each other, requiring separate appointments, and communicating each other much more rarely. Health care professionals working with adults may also be less aware of spina bifida because it is considered a chronic health condition of childhood. Due to the difficulties that may occur in the transition period, adolescents with spina bifida and their families are encouraged to begin preparing for the transition around age 14-16, although this may vary depending on the cognitive and physical abilities of teenagers and available family support. The transition itself must be gradual and flexible. Teens multidisciplinary teams can assist in the process by preparing a comprehensive and updated document detailing adolescent medical care, including information on medicines, surgery, therapy, and recommendations. Transition plans and assistance in identifying adult health care professionals also help to be included in the transition process.
Further complicating the transition process is the tendency for youth with spina bifida to be suspended in the development of autonomy, with boys especially at risk for a slower progression of independence. Increased dependence on others (especially family members) can disrupt adolescent self-management related to health-related tasks, such as catheterization, bowel management, and taking medication. As part of the transition process, it is useful to start discussions at an early age on educational and vocational goals, independent living, and community involvement.
Epidemiology
About 15% of people have spina bifida occulta. Other types of spina bifida vary significantly by country from 0.1 to 5 per 1000 births. The average in developed countries occurs at about 0.4 per 1,000 births. In the United States it affects about 0.7 per 1,000 births, and in India about 1.9 per 1,000 births. Part of this difference is believed to be race, with Caucasians at high risk, and partly due to environmental factors.
In the United States, the rate is higher in the East Coast than on the West Coast, and is higher in whites (one case per 1000 live births) than in blacks (0.1-0.4 cases per 1000 live births). Immigrants from Ireland have a higher incidence of spina bifida than indigenous peoples. The highest defect rate in the US can be found in Hispanic teenagers.
The highest incidence rates worldwide are found in Ireland and Wales, where three to four cases of myelomeningocele per 1000 populations have been reported during the 1970s, along with more than six cases of anencephaly (both live birth and stillbirth) per 1000 inhabitants. The overall reported incidence of myelomeningocele in the British Isles is 2.0-3.5 cases per 1000 births. Since then, that figure has fallen dramatically by 0.15 per 1,000 live births reported in 1998, although this reduction is partly taken into account because some fetuses are aborted when tests show signs of spina bifida (see Pregnancy screening above).
Research
- 1980 - Fetal surgical technique using animal models was first developed at the University of California, San Francisco by Michael R. Harrison, N. Scott Adzick and fellow researchers. 1994 - A surgical model that simulates human disease is a model of myelomeningocele fetal sheep (MMC) introduced by Meuli and Adzick in 1994. Defects such as MMC are surgically made at 75 days gestation (145 to 150 days)) with lumbo-sacral laminate. Approximately 3 weeks after the making of the defect, the upside-down latissimus flap is used to cover exposed neural plasods and the animals are born through cesarean section just before their time. Human-like MMC lesions with similar neurologic deficits are found in the control of newborns. In contrast, closing animals have near-normal neurologic function and a well-preserved cytoarchitecture architecture of a closed spinal cord on histopathologic examination. Although paraparesis are mild, they can stand, walk, perform demanding motor tests and show no sign of incontinence. In addition, the rear rear sensory function is present clinically and electrophysiologically confirmed. Further research shows that this model, when combined with lumbar spinal lung myelotomy, leads to herniation characteristics of the cerebellum of Chiari II malformation and that in uterine surgery restore normal anatomy of the cerebrospinal brain by stopping cerebrospinal fluid leakage through myelomeningocele lesions.
The surgeon at Vanderbilt University, led by Joseph Bruner, tries to close the spina bifida on 4 human fetuses using a skin graft from a mother using a laparoscope. Four cases were performed before stopping the procedure - two of the four fetuses died.
- 1998 - N. Scott Adzick and a team at The Children's Hospital of Philadelphia performed an open fetal surgery for spina bifida on the initial gestation (twenty-week gestation) with successful results. Fetal surgery is open to myelomeningocele involving abdominal surgery of pregnant women and uterus to operate on the fetus. The open fetal spinal cord is covered in layers with adjacent fetal tissue in mid-pregnancy (19-25 weeks) to protect it from further damage caused by prolonged exposure to amniotic fluid. Between 1998 and 2003, Dr. Adzick, and colleagues at the Center for Fetal Diagnosis and Treatment at Children's Hospital of Philadelphia, performed prenatal spina bifida improvements in 58 mothers and observed significant benefits in infants.
Fetal surgery after 25 weeks has not shown any benefit in subsequent studies.
MOMS experiment
Management of myelomeningocele studies (MOMS) is a Phase III clinical trial designed to compare two approaches to spina bifida treatment: preoperative and postnatal surgery.
The experiment concluded that results after prenatal spina bifida treatment increased to a level that the benefits of surgery outweigh the risks of the mother. This conclusion requires an assessment of the value on the relative value of the fetal outcome and the mother in which the opinion is still divided.
To be more specific, the study found that prenatal improvements resulted in:
- Reversal of herniated rear cerebral components from Chiari II malformation
- Reduce the need for ventricular shunting (a procedure in which a thin tube is inserted into the ventricle of the brain to drain fluid and remove hydrocephalus)
- Reduces the incidence or severity of potentially damaging neurological effects caused by spinal exposure to amniotic fluid, such as impaired motor function
At the age of one year, 40 percent of children in the prenatal surgical group had received a shunt, compared with 83 percent of the children in the postnatal group. During pregnancy, all fetuses in the trial have a rear cerebral herniation. However, by the age of 12 months, one-third (36 percent) of infants in the prenatal surgical group no longer had evidence of rear cerebral herniation, compared with only 4 percent in the postnatal surgical group. Further supervision is in progress.
Fetoscopic surgery
In contrast to the open fetal surgical approach performed on MOMS experiments, a minimally invasive fetoscopic approach (similar to 'keyhole' surgery) has been developed. This approach has been evaluated by independent authors of controlled studies that show some benefits to survivors, but others are more skeptical
The observations of their mother and fetus performed over the last two and a half years with a mature invasive minimization approach show the following results: Compared with open fetal surgery, fetoscopic myelomeningocele improvements resulted in much less surgical trauma in the mother. , because a large incision in the abdomen and uterus is not necessary. Instead, the initial prick has a diameter of 1.2 mm only. Consequently, depletion of the uterine wall or dehiscence has been one of the most alarming and criticized complications after an open-operative approach does not occur after minimally invasive fetoscopic closure of the spina bifida aperta. The risk of maternal chorioamnionitis or fetal death as a result of the fetoscopic procedure goes below 5%. Women come home from hospital one week after procedure. There is no need for administration of chronic tocolytic agents since postoperative uterine contractions are hardly ever observed. The current cost of the entire fetoscopic procedure, including hospital care, medication, perioperative clinical examination, ECG, ultrasound and MRI, is about EUR16,000.
In 2012, the results of this fetoscopic approach were presented at various national and international meetings, among them at the 1st European Symposium on "Fetal Surgery for Spina bifida" in April 2012 at Giessen, at the 15th Congress of the German Society for Prenatal Medicine and Obstetrics in May 2012 in Bonn, at the World Congress of Fetal Medicine Foundation in June 2012 and at the World Congress of the International Society of Obstetrics and Gynecology (ISUOG) in Copenhagen in September 2012, and published in abstract form.
Since then more data has emerged. In 2014, two papers were published in fifty-one patients. This paper shows that risk to the little mother. The main risk seems to be preterm labor, on average about 33 weeks.
See also
- Rachischisis
- Sinus sinus sinus
References
External links
- Spina bifida in Curlie (based on DMOZ)
- CDC: Spina bifida
Source of the article : Wikipedia
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