Spina BifidaSpina Bifida

指導指導 :: 洪正修主任洪正修主任 報告報告 :: 邱士芸 邱士芸

Case-basic dataCase-basic data

Name:Name: 黃女士黃女士Age: 34 y/oAge: 34 y/o

G2P1( twins)G2P1( twins)

Previous pregnant history:Previous pregnant history:

Pregnancy 34 weeks with twins s/p C/SPregnancy 34 weeks with twins s/p C/S

2000g and 1700 g2000g and 1700 g

No other systemic disease.No other systemic disease.

Current conditionCurrent condition

Pregnancy 35+4 weeks with twinsPregnancy 35+4 weeks with twins

Transfer from VGHTCTransfer from VGHTC

One fetus—spina bifidaOne fetus—spina bifida

Spina BifidaSpina Bifida

The human nervous system develops from a smThe human nervous system develops from a small, specialized plate of cells along the back of aall, specialized plate of cells along the back of an embryo. n embryo.

Early in development, the edges of this plate begEarly in development, the edges of this plate begin to curl up toward each other, creating the neurin to curl up toward each other, creating the neural tube—a narrow sheath that closes to form the al tube—a narrow sheath that closes to form the brain and spinal cord of the embryo. brain and spinal cord of the embryo.

the top of the tube becomes the brain and the rethe top of the tube becomes the brain and the remainder becomes the spinal cord. mainder becomes the spinal cord.

This process is usually complete by the 28This process is usually complete by the 28th day of pregnancy. th day of pregnancy.

But if problems occur during this process, tBut if problems occur during this process, the result can be brain disorders called he result can be brain disorders called neuneural tube defectsral tube defects, including , including spinaspina bifidabifida. .

What is spina bifida?What is spina bifida?

Spina bifida, which literally means “cleft spine,” iSpina bifida, which literally means “cleft spine,” is characterized by the incomplete development s characterized by the incomplete development of the brain, spinal cord, and/or meninges.of the brain, spinal cord, and/or meninges.

Spina bifida is one of the more common birth deSpina bifida is one of the more common birth defects in the United States. fects in the United States.

It is among the most common severe birth defectIt is among the most common severe birth defects in the United States, affecting 1,500 to 2,000 bs in the United States, affecting 1,500 to 2,000 babies (one in every 2,000 live births) each year. abies (one in every 2,000 live births) each year.

the different types of spina bifida the different types of spina bifida

OccultaOcculta: is the mildest and most common : is the mildest and most common form in which one or more vertebrae are mform in which one or more vertebrae are malformed. alformed. The name “occulta,” which means “hidden,The name “occulta,” which means “hidden,” indicates that the malformation, or openin” indicates that the malformation, or opening in the spine, is covered by a layer of skin.g in the spine, is covered by a layer of skin.    This form of spina bifida rarely causes disaThis form of spina bifida rarely causes disability or symptoms.  bility or symptoms. 

Closed neural tube defectsClosed neural tube defects make up the secon make up the second type of spina bifida. d type of spina bifida.

This form consists of a diverse group of spinal dThis form consists of a diverse group of spinal defects in which the spinal cord is marked by a mefects in which the spinal cord is marked by a malformation of fat, bone, or membranes. alformation of fat, bone, or membranes.

In some patients there are few or no symptoms; iIn some patients there are few or no symptoms; in others the malformation causes incomplete parn others the malformation causes incomplete paralysis with urinary and bowel dysfunction. alysis with urinary and bowel dysfunction.

meningocelemeningocele : :the meninges protrude frothe meninges protrude from the spinal opening, and the malformatiom the spinal opening, and the malformation may or may not be covered by a layer of n may or may not be covered by a layer of skinskin..

Some patients with meningocele may havSome patients with meningocele may have few or no symptoms while others may exe few or no symptoms while others may experience symptoms similar to closed neuraperience symptoms similar to closed neural tube defects. l tube defects.

MyelomeningoceleMyelomeningocele :is the most severe a :is the most severe and occurs when the spinal cord is exposed nd occurs when the spinal cord is exposed through the opening in the spine, resulting through the opening in the spine, resulting in partial or complete paralysis of the parts in partial or complete paralysis of the parts of the body below the spinal opening.  of the body below the spinal opening.    The paralysis may be so severe that the aThe paralysis may be so severe that the affected individual is unable to walk and maffected individual is unable to walk and may have urinary and bowel dysfunction.y have urinary and bowel dysfunction.  

What causes spina bifida?What causes spina bifida?

The exact cause of spina bifida remains a mysteThe exact cause of spina bifida remains a mystery.  ry.  No one knows what disrupts complete closure of No one knows what disrupts complete closure of the neural tube, causing a malformation to develthe neural tube, causing a malformation to develop. op. Scientists suspect Scientists suspect genetic, nutritional, and envgenetic, nutritional, and environmental factorsironmental factors play a role.  play a role. it appears to result from a combination of genetic it appears to result from a combination of genetic and environmental risk factors, such as a family and environmental risk factors, such as a family history of neural tube defects, folic acid deficienchistory of neural tube defects, folic acid deficiency and medical conditions such as diabetes and oy and medical conditions such as diabetes and obesity. besity.

Risk factorsRisk factors

Race. Race. Spina bifida is more common among Hispanics anSpina bifida is more common among Hispanics and whites of European descent. d whites of European descent. Family history of neural tube defects. Family history of neural tube defects. Couples who've Couples who've had one child with a neural tube defect have a slightly hihad one child with a neural tube defect have a slightly higher chance of having another baby with the same defecgher chance of having another baby with the same defect. That risk increases if two previous children have been t. That risk increases if two previous children have been affected by the condition. In addition, a woman who was affected by the condition. In addition, a woman who was born with a neural tube defect, or who has a close relativborn with a neural tube defect, or who has a close relative with one, has a greater chance of giving birth to a child e with one, has a greater chance of giving birth to a child with spina bifida. However, most babies with spina bifida with spina bifida. However, most babies with spina bifida are born to parents with no known family history of the care born to parents with no known family history of the condition. ondition.

Folic acid deficiency. Folic acid deficiency. This vitamin is important This vitamin is important to the healthy development of a fetus. Lack of folto the healthy development of a fetus. Lack of folic acid (vitamin B-9) increases the risk of spina bic acid (vitamin B-9) increases the risk of spina bifida and other neural tube defects. ifida and other neural tube defects.

Some medications.Some medications. Anti-seizure medications, s Anti-seizure medications, such as valproic acid (Depakene), seem to cause uch as valproic acid (Depakene), seem to cause neural tube defects when taken during pregnancneural tube defects when taken during pregnancy, perhaps because they interfere with the body, perhaps because they interfere with the body's ability to use folic acid. y's ability to use folic acid.

Diabetes. Diabetes. The risk of spina bifida increases with The risk of spina bifida increases with diabetes, especially when the mother's blood sudiabetes, especially when the mother's blood sugar is elevated early in her pregnancy. Much of tgar is elevated early in her pregnancy. Much of this risk is preventable by careful blood sugar cohis risk is preventable by careful blood sugar control and management. ntrol and management. Obesity.Obesity. There's a link between pre-pregnancy There's a link between pre-pregnancy obesity and neural tube birth defects, including sobesity and neural tube birth defects, including spina bifida. Obese women may have more babiepina bifida. Obese women may have more babies with spina bifida possibly because of nutritional s with spina bifida possibly because of nutritional deficits from poor eating habits or because they deficits from poor eating habits or because they may have diabetes. may have diabetes.

Increased body temperature.Increased body temperature. Some evid Some evidence suggests that increased body temperence suggests that increased body temperature (hyperthermia) in the early months of ature (hyperthermia) in the early months of pregnancy may increase the risk of spina pregnancy may increase the risk of spina bifida. bifida.

ComplicationsComplications

Factors that affect the severity of complications incFactors that affect the severity of complications include: lude: The size and location of the neural tube defect .The size and location of the neural tube defect .Whether skin covers the affected area Whether skin covers the affected area Whether spinal nerves come out of the affected Whether spinal nerves come out of the affected area of the spinal cord.area of the spinal cord.Children with myelomeningocele may experiencChildren with myelomeningocele may experience physical and neurological problems, including le physical and neurological problems, including lack of normal bowel and bladder control, and paack of normal bowel and bladder control, and partial or complete paralysis of their legs. rtial or complete paralysis of their legs.

Babies born with myelomeningocele also commBabies born with myelomeningocele also commonly experience accumulation of fluid in the brain,only experience accumulation of fluid in the brain, a condition known as hydrocephalus. a condition known as hydrocephalus.

Most babies with myelomeningocele will need a Most babies with myelomeningocele will need a shunt .shunt .

The majority of newborns with myelomeningocelThe majority of newborns with myelomeningocele survive. e survive.

some may develop meningitis, an infection in the some may develop meningitis, an infection in the tissues surrounding the brain tissues surrounding the brain

Children with myelomeningocele may devChildren with myelomeningocele may develop learning disabilities.elop learning disabilities.

Children with spina bifida may also suffer fChildren with spina bifida may also suffer from latex allergies, skin problems, urinary rom latex allergies, skin problems, urinary tract infections, gastrointestinal disorders, tract infections, gastrointestinal disorders, seizure disorders, depression, and social aseizure disorders, depression, and social and emotional problems. nd emotional problems.

Screening and diagnosisScreening and diagnosis

(1)Blood tests(1)Blood tests second trimester maternal serum alpha fetoprotesecond trimester maternal serum alpha fetoprotein (MSAFP) in (MSAFP) alpha-fetoproteinalpha-fetoprotein (AFP) is made naturally by the (AFP) is made naturally by the fetus and placenta.  fetus and placenta.  But if abnormally high levels of this protein appeBut if abnormally high levels of this protein appear in the mother’s bloodstream it may indicate thar in the mother’s bloodstream it may indicate that the fetus has a neural tube defect. at the fetus has a neural tube defect. The MSAFP test, however, is not specific for spiThe MSAFP test, however, is not specific for spina bifida.na bifida.

UltrasoundUltrasound: An advanced ultrasound can also detect sig: An advanced ultrasound can also detect signs of spina bifida.ns of spina bifida.AmniocentesisAmniocentesisAn analysis indicates the level of AFP present in the amnAn analysis indicates the level of AFP present in the amniotic fluid. iotic fluid. A small amount of AFP is normally found in amniotic fluid.A small amount of AFP is normally found in amniotic fluid. when an open neural tube defect is present, the amniotic when an open neural tube defect is present, the amniotic fluid contains an elevated amount of AFP because the skfluid contains an elevated amount of AFP because the skin surrounding the baby's spine is gone and AFP leaks inin surrounding the baby's spine is gone and AFP leaks into the amniotic sac. to the amniotic sac. MRIMRI

TreatmentTreatment

There is no cure for spina bifida. There is no cure for spina bifida.

The nerve tissue that is damaged or lost cThe nerve tissue that is damaged or lost cannot be repaired or replaced.annot be repaired or replaced.

Treatment depends on the type and severiTreatment depends on the type and severity of the disorder. ty of the disorder.

children with the mild form need no treatmchildren with the mild form need no treatment .ent .

The key priorities for treating myelomeningThe key priorities for treating myelomeningocele are to prevent infection from developocele are to prevent infection from developing through the exposed nerves and tissue ing through the exposed nerves and tissue of the defect on the spine, and to protect tof the defect on the spine, and to protect the exposed nerves and structures from adhe exposed nerves and structures from additional trauma. ditional trauma. Doctors have recently begun performing Doctors have recently begun performing fefetal surgerytal surgery for treatment of myelomeningo for treatment of myelomeningocele. cele.

Fetal surgery involves opening the mother’s abdFetal surgery involves opening the mother’s abdomen and uterus and sewing shut the opening oomen and uterus and sewing shut the opening over the developing baby’s spinal cord.  ver the developing baby’s spinal cord. 

They believe the earlier the defect is corrected, tThey believe the earlier the defect is corrected, the better the outcome is for the baby.he better the outcome is for the baby.

Still, the benefits of fetal surgery are promising, Still, the benefits of fetal surgery are promising, and include less exposure of the vulnerable spinand include less exposure of the vulnerable spinal nerve tissue and bones to the intrauterine envial nerve tissue and bones to the intrauterine environment, in particular the amniotic fluid, which is ronment, in particular the amniotic fluid, which is considered toxic. considered toxic.

Early surgery on the spinal cord may allow the cEarly surgery on the spinal cord may allow the child to regain a normal level of functioning and prhild to regain a normal level of functioning and prevent further neurological deterioration. event further neurological deterioration. Some children will need subsequent surgeries to Some children will need subsequent surgeries to manage problems with the manage problems with the feet, hips, or spinefeet, hips, or spine. . Individuals with Individuals with hydrocephalushydrocephalus generally will re generally will require additional surgeries to replace the quire additional surgeries to replace the shuntshunt Some individuals with spina bifida require assistiSome individuals with spina bifida require assistive devices such as ve devices such as braces, crutches, or wheelbraces, crutches, or wheelchairschairs.  The .  The location of the malformationlocation of the malformation on t on the spine often indicates the type of assistive devhe spine often indicates the type of assistive devices needed.  ices needed. 

Treatment for paralysis and bladder and bTreatment for paralysis and bladder and bowel problems typically begins soon after owel problems typically begins soon after birth birth

Prevention Prevention

Folic acid is an important vitamin in the developFolic acid is an important vitamin in the development of a healthy fetus.ment of a healthy fetus.

Recent studies have shown that by adding folic Recent studies have shown that by adding folic acid to their diets, women of childbearing age sigacid to their diets, women of childbearing age significantly reduce the risk of having a child with a nificantly reduce the risk of having a child with a neural tube defect, such as spina bifida.   neural tube defect, such as spina bifida.  

Dosage:400 micrograms of folic acid daily Dosage:400 micrograms of folic acid daily

Foods high in folic acid include dark green vegetFoods high in folic acid include dark green vegetables, egg yolks, and some fruits. ables, egg yolks, and some fruits.

prognosis prognosis

Prognosis depends on the number and sePrognosis depends on the number and severity of abnormalities and associated comverity of abnormalities and associated complications. plications.