The Hydrocephalus Is a pathology in which there is an excessive and abnormal accumulation of cerebrospinal fluid at the brain level (National Institute of Neurological Disorders and Stroke, 2014).
Cerebrospinal fluid (CSF) acts to protect and cushion the brain and its structures and is produced and absorbed on a constant basis. Hydrocephalus, therefore, occurs when an imbalance develops between production and absorption or elimination (National Hydrocepahlys Foundaton, 2014).
Excessive fluid buildup causes the brain ventricles to expand. As a result, the spreading will generate pressure on other structures causing severe damage, which may lead to extensive neurological symptoms (National Hydrocepahlys Foundaton, 2014).
Hydrocephalus can affect a large number of people, from newborns, older children, adults, to the elderly or elderly. In addition, it can have several causes, both acquired and generated before birth (Hydrocephalus Association, 2016).
Currently, hydrocephalus is a neurological pathology that is treated through the use of a surgical procedure, derivation. It is a relatively common intervention, in which the passage of the cerebrospinal fluid is channeled to another place of the body (Hydrocephalus Association, 2016).
Although neurological complications may occur, in most cases therapeutic procedures usually cure the disease, although there are occasions when hydrocephalus may remain chronic (Hydrocephalus Association, 2016).
What is Hydrocephalus?
The word hydrocephalus comes from the Greek terms 'Hydro' meaning water and 'cephali' meaning head. Since ancient times, this pathology has been identified with an accumulation or collection of fluid at the cerebral level (Malagón-Valdez, 2006).
Currently, we know that hydrocephalus is an accumulation of cerebrospinal fluid In the cerebral cavities, in the cerebral ventricles. Excess fluid increases the size of the ventricles and puts pressure on different brain structures (Mayo Clinic, 2014).
Our body produces about half a liter of CSF daily and replaces it constantly. Under normal conditions, there is a fine balance between the amount produced and the amount absorbed.
There are many factors that can alter CSF balance, and thus cause abnormal accumulation of CSF (Hydrocephalus Association, 2016).
Depending on the cerebral structures that are affected by the obstruction and the pressure, several complications and neurological manifestations appear at clinical level: headache, vomiting, psychomotor retardation, macrocephaly, strabismus, among others (Puche Mira, 2008).
About us
Generally, hydrocephalus occurs more frequently in children and in adults over 60 years of age (Delgado & Higuera, 2015).
Although there is no large volume of statistical data on the incidence and prevalence of hydrocephalus, it is estimated that in the case of children, this pathology may affect 1 in 500 (National Institute of Neurological Disorders and Stroke, 2014).
Currently, most cases of childhood hydrocephalus are diagnosed in the prenatal, birth, or early years (National Institute of Neurological Disorders and Stroke, 2014).
What is Cerebrospinal Fluid (CSF)?
Our nervous system is completely bathed by cerebrospinal fluid (CSF). This liquid contains proteins, electrolytes and some cells. In addition to protecting against possible trauma, cerebrospinal fluid plays an important role in the maintenance of cerebral homeostasis, through its nutritional, immunological and inflammatory function (Chauvet and Boch, X).
Cerebrospinal fluid (CSF) occurs within the cerebral ventricles in the choroid plexus and flows into the subarachnoid spaces (between the meningeal layers) on the cerebral and spinal surfaces, where it is reabsorbed (Puche Mira, 2008).
Usually, in adults, we can find approximately 130-150 ml of cerebrospinal fluid (Puche Mira, 2008) and have several essential functions (National Institute of Neurological Disorders and Stroke, 2014):
- Protect the brain and spinal cord. Cushioning mechanism acting.
- Transporting nutrients and eliminating waste.
- Flow between the skull and spine to compensate for changes in intracranial blood volume and prevent an increase in pressure.
symptom
Depending on the nervous structures that are affected by hydrocephalus, the symptoms can change considerably among the people who suffer. Despite this the Mayo Clinic (2014) points out some of the most common symptoms:
Physical symptoms
- Variable headache, headaches.
- Blurred or double vision (diplopia).
- Cranial volume normally elevated (Macrocephaly).
- Drowsiness.
- Difficulty waking or staying awake.
- Nausea and vomiting.
- Difficulty of coordination.
- Unstable equilibrium.
- Loss of appetite.
- Convulsive episodes.
Cognitive and behavioral changes
- Difficulty maintaining The attention Y concentration .
- Psychomotor retardation.
- Difficulties and forgetfulness in previously acquired skills (walking, talking, etc.).
- Irritability.
- Changes in personality traits.
- Decreased school performance / work.
Regarding age and symptoms related to different groups, we can highlight (Mayo Clinic, 2014):
Most common symptoms in young and middle-aged adults
- Inability or serious difficulties to stay awake.
- Significant loss of balance and motor coordination.
- Loss of sphincter control.
- Difficulties of vision.
- Deficits in memory, concentration and other skills that can affect routine performance.
Most common symptoms in adults 60 years of age or older
- Loss of control of the sphincters or a recurrent urge to urinate.
- More severe memory deficits.
- Progressive loss of reasoning and problem solving skills.
- Difficulty walking (shuffling feet, immobility of feet, poor balance, etc.).
- Reduction of the speed of execution of movements.
In the case of infants and young children, the following symptoms will be considered as severe indicators of hydrocephalus (Mayo Clinic, 2014):
- Recurrent vomiting.
- Inability to perform voluntary movements with the neck or head.
- Respiratory distress.
- Convulsive episodes.
- Difficulties of suction and feeding.
Types of hydrocephalus
Throughout the medical and scientific literature we can identify some terms that have been used to distinguish between different types of hydrocephalus (Chauvet and Boch, X):
- External hydrocephalus : Enlargement of the frontal subarachnoid space, with normal ventricular volume and without clinical results or repercussions.
- Hydrocephalus ex vacuo : It is an increase of volume of the ventricles with a reduction of the cerebral gray matter, it is possible to be observed in people of advanced age and does not have to be the result of a hydrocephalus.
- Interrupted hydrocephalus : This is hydrocephalus that occurs as a consequence of a dysfunction in the balance of the mechanisms of reabsorption. It usually presents localized ventricular dilatation without the development of significant symptoms.
H Communicating / non communicating hydrocephalus : This is a hydrocephalus that occurs as a consequence of the presence of an obstruction in the flow of cerebrospinal fluid. In the case of the communicant the obstacle is in the arachnoid villi (choroid plexus) and the non communicating obstacle is proximal.
In addition, we can also distinguish different types of hydrocephalus depending on the time of presentation (National Institute of Neurological Disorders and Stroke, 2014):
- Congenital hydrocephalus : This type of hydrocephalus is already present at the time of birth and is a product of the events or influences that takes place during embryonic development
- Acquired hydrocephalus : This type of hydrocephalus can develop at birth or later. In addition, it can affect people of any age and is caused by different types of pathologies and / or injuries.
Causes
Hydrocephalus, as defined above, occurs as a result of an excessive accumulation of cerebrospinal fluid and this may be due to (Mayo Clinic, 2014):
- Obstruction : Clogged cerebrospinal fluid is one of the most common problems, from one ventricle to another or between the ventricle and the rest of the pathways.
- Poor Absorption : Deficits in the mechanisms of resorption of cerebrospinal fluid are less frequent. They are usually associated with tissue inflammation due to various injuries or diseases at the brain level.
- Overproduction : In some cases, although scarce, the mechanisms responsible for the production of cerebrospinal fluid can produce high amounts of this and more rapidly than can be absorbed.
There is a wide variety of medical conditions that may lead to the development of either obstruction, poor absorption or overproduction of cerebrospinal fluid. Some of the most frequent medical problems are (Hydrocephalus Association, 2016):
- Acueductal Obstruction (Stenosis): this is the most common cause of congenital hydrocephalus in which there is an obstruction of the passageway that connects the third to the fourth ventricle. Infections, bleeding or tumors can cause a narrowing or blockage of the aqueduct.
- Spina Bifida : the Spina bifida Is a pathology in which there is a defect in the closure of the spinal canal and surrounding vertebrae. In a high percentage of cases, children with spina bifida Chiari Syndrome Type II, a cerebral malformation that causes a block the flow of cerebrospinal fluid.
- Intraventricular Hemorrhage : Intraventricular hemorrhages are one of the causes that can lead to the development of an acquired hydrocephalus and takes place when there is a rupture of the blood vessels that extend through the ventricular tissue. The accumulation of blood can block and block the passage of cerebrospinal fluid.
- Meningitis : the meningitis Is a type of pathology in which there is a severe inflammation of the membranes that cover the brain and spinal cord . The action of different viruses or bacteria can cause scarring of different areas of the meninges and therefore restrict the passage of cerebrospinal fluid through the subarachnoid space.
- Cranioencephalic injury : Like other conditions, a trauma or blow to the skull can damage nerve tissues. When this occurs, the blood or inflammation of these tissues can enter both the CSF flow pathways and compress them.
- Tumors : Tumors that are general or reach the brain can compress both the cerebral ventricles and adjacent areas, blocking the passage of the brain and spinal fluid.
- Arachnoid cysts : Arachnoid cysts are one of the congenital causes and although they may appear in any part of the brain, in children they are more common in the posterior region and the third ventricles. Cysts develop as sacs filled with cerebrospinal fluid covered by the arachnoid membrane and therefore, this formation may block the ventricular passages.
- Dandy Walker's Syndrome : at Dandy Walker syndrome Various brain abnormalities may occur, among which are a widening of the fourth ventricle and / or obstruction of the Silvio's aqueduct , Therefore, cerebrospinal fluid flow systems may also be interrupted.
Diagnosis
Due to the fact that different factors or etiologies can lead to the development of problems related to hydrocephalus, it is essential to make an accurate diagnosis.
As in other neurological pathologies, the general diagnosis of hydrocephalus is based on (Mayo Clinic, 2014):
- Anamnesis
- Physical exam
- Neurological examination
- Brain imaging: magnetic resonance imaging, computerized tomography, ultrasound (prenatal).
Treatment
The most common treatment for hydrocephalus is surgical intervention through a bypass procedure (National Institute of Neurological Disorders and Stroke, 2014).
Use of a shunt system involves the placement of a tube, catheter, or valve that redirects the flow of cerebrospinal fluid from the central nervous system to another area of the organism where it can be reabsorbed (National Institute of Neurological Disorders and Stroke, 2014).
Specifically, one end of the catheter is placed in the central nervous system, within the cerebral ventricle, cyst or area near the spinal cord. The other end is commonly implanted in the abdominal area, within the peritoneal cavity. A valve located along the catheter is responsible for controlling and maintaining the direction and amount of cerebrospinal fluid to be reabsorbed (National Institute of Neurological Disorders and Stroke, 2014).
Although they usually work in most chaos, bypass systems are imperfect. Mechanical failures, infections, obstructions, etc. may occur.
References
- Chauvet, D., & Boch, A.L. (2015). Hydrocephalus. Treaty of Medicine.
- HE HAS. (2016). Hydrocephalus. Obtained from Hydrocephalus Association.
- Hydrocephaluskid. (2009). About Hydrocephalus. Retrieved from the Pediatric Hydrocephalus Foundation.
- Malagón-Valdez. (2006). Congenital hydrocephalus. Neonatal Symposium Neurology, 39-44.
- NHF. (2014). National Hydrocepahlus Foundation. Obtained from Hydrocephalus defined.
- NIH. (2014). Hydrocephalus Fact Sheet. Retrieved from the National Institute of Neurological Disorders and Stroke.
- Puche Mira, A. (2008). Hydrocephalus - Ventricular collapse syndrome. Therapeutic Diagnostic Protocols of the AEP. Pediatric Neurology.