The mildest form of spina bifida, spina bifida occulta describes a group of neural tube birth defects that can affect the spinal column. This is composed of bones, or vertebrae, which support the nerve center of the spinal cord, which is responsible for carrying all nerve signals in between the body and the brain.
Most people are unaware that they have spina bifida occulta, although an estimated 10 to 20% of the population carries this type of condition. There may be no outward sign of any defects in the spinal column until an X-ray is carried out for some other reason, because in this type of spina bifida there aren’t any problems with the nervous system.
Signs of Spina Bifida Occulta
Although in most cases there will be no outward signs or symptoms, there can be a few warning signs that this defect is present. These can include the following visible signs, one of which will be present in approximately 80% of individuals who have spina bifida occulta:
- Hairy patch on the skin
- Dark spots or birth marks
- A red or purple spot on the back composed of blood vessels
- Dimpling in the back
- An area that has less skin color than other areas
There is no cause for concern should an individual have any of these outward signs, as no treatment will be necessary. In more serious cases, however, there can be some symptoms which affect quality of life. These can include:
- Numbness or loss of sensation in the legs
- Weakness or mild pain in the lower half of the body
- Changes in bowel or bladder function
If experiencing any of these more serious signs of spina bifida, it’s best to visit a doctor for diagnosis and treatment. These may or may not be related to spinal cord damage.
Types of Occulta
Although occulta is a type of spina bifida, it is still a term used to describe a series of birth defects which could take on different forms. These could include the following:
- Spinal cord ending is too thick
- Tethered spinal cord – the lower end of the spinal cord does not attach to the rest of the body, allowing it to potentially get damaged or stretched out
- Fatty lumps inside of the spinal cord
- Split spinal cord – the cord is split into two halves
- The skin of the back and the spinal canal are connected by tissue
Diagnosis of Spina Bifida Occulta
Because there may be no apparent outward signs of occulta, it can be more difficult to diagnose than other forms of spina bifida. There are a few steps that a mother can take to find out if her baby is going to have this defect. Blood testing can be carried out in the second trimester of pregnancy, which can be followed up with an ultrasound or amniocentesis should suspect levels of maternal protein be found in the blood.
After birth, it’s possible to diagnose this disorder with ultrasound technology in the case of newborns. Older children and adults will need to have an MRI scan in order to confirm the presence of spina bifida occulta, and then work out a treatment plan if necessary.
Causes of Spina Bifida Occulta
At the moment, there is no singular cause which has been linked to this type of neural tube defect. However, there are a few other factors which may make an individual more likely to be diagnosed with this condition. Those who have a parent or sibling with spina bifida are about 8 times more likely to have this disorder as well.
Spina bifida occulta has also been linked to a lack of folic acid in the mother’s diet. For this reason, healthcare professionals now recommend that all pregnant women take 400 micrograms of folic acid every day in order to help lower their chances of giving birth to a baby with this birth defect.