The three main forms of Spina Bifida are
CYSTICA (Cyst-like), OCCULTA (Hidden) & CRANIUM BIFIDA
IT IS NOT UNUSUAL FOR HYDROCEPHALUS TO BE PRESENT IN ALL FORMS OF SPINA BIFIDA
HYDROCEPHALUS
Four out of five babies born with Spina Bifida will also have Hydrocephalus. This can be due to problems with the development of certain parts of the brain before birth.
Hydrocephalus is commonly known as ‘water on the brain’ this is a inaccurate description. A fluid known as Cerebro-Spinal-Fluid (CSF) is produced continually within each of the four spaces inside the brain. The CSF flows from one space to the next along narrow pathways after which it will flow over the brain and down the spinal cord. The CSF is absorbed into the blood stream keeping the CSF at a fairly closely governed pressure. Any obstructions in the system preventing the flow of CSF from draining away will cause the fluid to accumulate in the passages within the brain causing them to swell which will result in compression of the surrounding tissue, in babies and infants the head will become enlarged due to internal swelling inside the brain.
With children and adults the bones that make up the skull are completely joined they are therefore unable to give way to ease the pressure on the brain.
Causes: There are many. Listed below are just a few of them.
Brain Haemorrhage. Other forms of brain haemorrhage including those occurring in adults can result in post-haemorrhage hydrocephalus.
Brain Tumours. If the swelling due to the tumour causes the pathways to become obstructed the CSF may not drain correctly. Hopefully in these cases hydrocephalus may only be temporary.
Premature Birth. A baby that is premature is more at risk than one that has gone the full term. If (and only if) hydrocephalus does occur it can be for many reasons, some of which are either not too clear or just unknown.
Brain Infection. (ie. Meningitis) Inflammation and debris from the infection can block the pathways resulting in hydrocephalus.
Congenital. This means that it is present at birth, the exact cause of congenital hydrocephalus may not always be easy to determine (if at all).
Genetic. Hereditary hydrocephalus is very rare but it does happen.
Cystica. The signs are a Sac or a Cyst on the back, a bit like a large blister. There are two forms of this type.
Meningocele. In this form the sac or cyst contains mainly tissues and CSF (Cerebro-Spinal-Fluid). The nerves are not usually too badly damaged therefore there may be very little disability present. This is the least common form of Spina Bifida.
Myelomeningocele. In this form the sac or cyst may not only contain tissues and CSF but also nerve and part of the spinal cord. A child born with this form of spina bifida may well be very seriously disabled indeed and as such may need the help of others for most or even all their lives. This form of spina bifida is not only the most serious it is also the most common form as well.
Occulta. This is a very mild and common form which may cause very slight disability (if any at all), most people who have this form may never be aware of it.
Cranium Bifida. Unlike Spina Bifida where the problem is caused by the failure of one or more of the vertebrae to form properly leaving a split in the spine, here it is the bones in the skull that fail to form correctly. The sac that forms here is called Encephalocele, as well as CSF and tissue it may well contain in some cases parts of the brain. The worst cases Iniencephaly and Anocephaly. With these forms the brain fails to develop properly or may be absent a the baby will be stillborn or almost certainly die shortly after birth.
