Spina Bifida Case Study

Spina bifida, which literally means “cleft spine,” is characterized by the incomplete development of the brain, spinal cord, and/or meninges, the protective covering around the brain and spinal cord. Meningomyelocele is the most severe type Spina Bifida, and requires surgery as treatment. It happens when parts of the spinal cord and nerves come through the open part of the spine. It causes nerve damage and decreased motor function. . Despite aggressive intervention, nearly 14% of all Spina Bifida neonates do not survive past 5 years of age, with the mortality rising to 35% in those with symptoms of brainstem dysfunction secondary to the Arnold–Chiari malformation (Oakeshott 2003).

Some structural anomalies are virtually unique to individuals with SBM, including a complex pattern of cerebellar dysplasia known as the Chiari II malformation. This can cause negative effects on brain

development such as language processing, coordination, and reasoning. It is typically referred to as myelomeningocele and the most serious type that affects approximated 1 in every 1,000 babies born (CDC 1991). From 1970 to 1977 in United States, incidence of Spina Bifida decreased 6.7% per year, before folic acid supplementation was prevalent (CDC 1991). The purpose of this literature review is to discuss the causes of Spina Bifida and fetal surgery as the preferred treatment option for Spina Bifida
Causes
There is no known cause of Spina Bifida. Experts believe it may be hereditary and may have to do with folic deficiency. Environmental factors such as radiation can also be a risk factor. Some factors that can increase risks can be obesity and diabetes in pregnant women. It is also more likely to happen to a woman who has already had a fetus that was diagnosed with Spina Bifida. The risk for Spina bifida or anencephaly, or both, in the siblings of affected individuals ranges from 3% to 8% and is consistently higher than that of the general population (Mitchell 2004).
Treatment
There is not much research to choose from different treatment options for spinal bifida. The common options for treatment are prenatal surgery and postnatal surgery. Fetal surgery is the new innovative way to treat Spina Bifida. Fetal surgery undergoes opening the abdomen and uterus to operate and applying a ventricular shunt in the fetus spinal cord. On the other hand, postnatal surgery undergoes surgical repair to correct the defects. In this review of Spinal Bifida treatment, the focus is dealing with the surgical treatment of prenatal surgery, often referred to as fetal surgery. It has proven to be more effective then postnatal alone. “Establishing fetal surgery for Spina bifida as a standard of care option was one of the most exciting developments in the history of the treatment for birth defects, and one that our CHOP team has spent years helping to pioneer," said N. Scott Adzick
The five most applicable and available research studies that posed research questions about fetal surgery involving spinal bifida proved it to be more effective. Johnson et al (2003) sampled 50 fetuses that went through open fetal MMC closure. Adrick et al (2011) concerns 158 mothers that undergo prenatal vs postnatal fetal surgery. The Khan et al. (2014) is a case study on a 19 year woman whose fetus went through open MMC closure. Danzer et al. (2011) observed a sample size of 54 preschool children that went through fetal MMC closure and recorded their neurodevelopment.
Of all the articles, Khan et al.

(2014) poses to be a treat to external validity. It only offers results from one patient .Although, successful it does not represent the population as a whole. It also continues to study the infants results as the mature into an adult, and the results may change in time. Results conclude fetal surgery allows for less shunting dependency and increased motor function. This study acknowledges fetal surgery as a new approach for Spina Bifida treatment and recommends it should it only performed in tertiary care.

Although these articles differ in sample size they state the same thing in that prenatal surgery is the most effective treatment for Spina Bifida, and is associated with less difficulties than postnatal surgery. Since, Spina Bifida is a progressive and there is no known cure, fetal surgery shows positive outcomes for participants that undergo this procedure. All the researchers felt strongly that prenatal surgery is a new upcoming way of treatment and should be only performed in multidisciplinary facilities that specialized in meningomyelocele

repair.

Adrick et al (2011) did a comparison between prenatal and postnatal surgery using 158 patients. They randomly assigned eligible women to a prenatal repair group or a postnatal group. Results included 40 percent shunt placement for prenatal and 82 percent shunt placement for postnatal .The result concluded prenatal provided a less risk for shunt placement then the postnatal group.. An obstacle they might face is external validity because the study had to be terminated for efficacy of prenatal surgeries.
A study conducted by Johnson et al. (2003) had a sample of 50 fetuses with a 94% survival rate. They reviewed how prenatal seem to have benefits on infants through the lower extremities dealing with lumbar and thoracic lesions. They focused on in utero surgery with a distinction in reversal in hindbrain herniation. A common defect that is associated with Spina Bifda. Chiari II deformity' or Arnold-Chiari deformity and is an intrauterine abnormality in which the fourth ventricle and medulla are grotesquely herniated before they are properly developed and the foramen magnum is enlarged (Willams 1981). A study conducted by Tulipan et al.(1999) observed 26 patients that underwent MMC closure through extensive MRI testing and manual muscle testing.
Danzer et al. (2011) study focused on toddlers who went through fetal surgery as infants. The patient’s neurodevelopment abilities were tested by psychologist and healthcare professionals until the age of 5. Although, selection bias may exist because parents were not required to bring children in every year to be tested. This allowed room for skewed results. In fact, only 56 % of the children showed up to take the neurodevelopmental examination at age 5. For this cohort study, MMC closure seem to reverse hindbrain herniation and reduces the need for ventricular shunting.
On the other hand, Tulipan et al. (1999) took another approach by analyzing the different testing methods available after a MMC closure procedure. Although, it did seem clear that intrauterine repair does reduce shunting, there still need to be more studies done. Several methods of testing such as MRI imaging and manual muscle testing provided and overview of lesions throughout the lower extremities. This study also tried to correlate intrauterine repair and leg function. Unfortunately, there seems to be no difference compared to postnatal surgery. The researchers concluded that there does seem to be a direct correlation with fetal surgery and reversal in hindbrain herniation.

Summary
Further research is recommended to be conducted on fetal surgery as the sole treatment for Spina Bifida. According to the articles, on this topic, fetal surgery proves to have benefits if the disease is detected early. Long-term follow ups can also shed light on effective intervention. However, this may not be the case for every pregnant women with a fetus that is diagnosed with Spina Bifdia .It all depends how far along they are in their pregnancy to make the best medical approach for the fetus. There needs to be more studies concentrating on prenatal care and postnatal care, rather than one or the other. Furthermore, research studies in less invasive techniques should be considered. The next step in research, should be more genetic testing to pinpoint the exact gene that causes this defect, so we can learn more information about it and essentially cure it.