Spina bifida is a birth defect that involves disrupted formation of a structure called the neural tube. In this video, I discuss spina bifida, focusing primarily on the most common form of spina bifida: myelomeningocele.

TRANSCRIPT:

Spina bifida is a birth defect that involves disrupted formation of a structure called the neural tube. The neural tube forms in early neural development, and eventually will become the brain and spinal cord. In spina bifida, the neural tube either does not form or close properly. This can result in three types of spina bifida: myelomeningocele, meningocele, and spina bifida occulta. The latter two forms are less common and do not typically cause any symptoms. Myelomeningocele, which is the most common form of spina bifida, is more likely to result in complications and disability.

In myelomeningocele, the failed closure of the neural tube leads to the disrupted formation of the spinal column and causes the spinal cord to be exposed. The spinal cord below the level of the defect does not develop properly, potentially resulting in a variety of neurological problems and associated symptoms, such as incontinence and weakness or paralysis in the legs. Additionally, the open lesion in the spinal column can cause cerebrospinal fluid leakage, which is thought to be connected to abnormalities in the size and shape of the ventricles as well as related brain conditions, such as Chiari II malformation and hydrocephalus.

Spina bifida is thought to be caused due to an interaction between genetic and nongenetic factors. There are a number of nongenetic risk factors for spina bifida, but the best established one is inadequate intake of folate or folic acid before and during early pregnancy. Although it’s not completely clear why low folate levels are linked to spina bifida, folate plays important roles in neural development and thus a deficiency is thought to have the potential to interfere with healthy development. Treatment for spina bifida typically involves closing the spinal lesion after birth (although prenatal surgery is also sometimes an option) and treating any associated problems, such as hydrocephalus.

REFERENCES:

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