Hydrocephalus Updates

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Transcript of Hydrocephalus Updates

HYDROCEPHALUSBY: MURNIWATI BINTI ZAKARIA

LEARNING OUTCOMESAT THE END OF THIS TOPIC , THE STUDENT WILL BE ABLE TO :

1.Define what is hydrocephalus 2. Explain cause and risk factors for hydrocephalus. 3. Explain the pathophysiology for hydrocephalus.

4.State symptoms for hydrocephalus. 5.Explain classification for hydrocephalus. 6.Explain laboratory and diagnostic test for hydrocephalus. 7.Explain treatment for hydrocephalus. 8. Explain nursing management for patient with hydrocephalus. 9.Explain nursing care plan for patient with hydrocephalus.

DEFINITION Condition caused by an imbalance in the

production and absorption of CSF in the ventricular system. When production exceeds absorption

,CSF accumulates ,usually under pressure ,producing dilation of the ventricles.

Greek words hydro meaning water , and cephalus meaning head . Sometime known as water in the brain

People with hydrocephalus : - abnormal accumulation of CSF in the ventricles ,or cavities ,of the brain. - this condition may increased intracranial pressure inside the skull and progressive enlargement of the head.,convulsion ,and mental disability.

hydrocephalus does not cause any

intellectual disability if treated properly.

CAUSE AND RISK FACTORS

is usually the result of a brain infection or a malformation in the fetus prior to birth. Although the baby's head may not appear abnormally large at birth, it expands rapidly from month to month. If untreated, the baby usually dies by the end of the second year. If the blockage of CSF is only partial, the child may live for a number of years or may even live a normal life span.

ETIOLOGY

Congenital hydrocephalus result from defects, such as Chairi malformations. ( abnormality of the lower part in the brain ( cerebellum ). Also associated with spina bifida. Acquired hydrocephalus results from spaceoccupying lesions, hemorrhage, intracranial infections or dormant development defects.

Hydrocephalus can be caused by

impaired cerebrospinal fluid ( CSF ) flow, re- absorption ,or excessive CSF production.

Common cause : - CSF flow obstruction hindering the free passage of the CSF through the ventricular system and sub-arachnoids space. ( eg. stenosis of the cerebral aqueduct or obstruction of the intervetricular foramina foramina of Monro (the small opening (on both the right and left sides) that connects the third ventricle in the diencephalons with the lateral ventricle in the cerebral hemisphere )

-

secondary to tumors ,hemorrhage ,infections or congenital malformations. Also cause by overproduction of CSF

( relative obstruction ) eg. *papilloma of choriod plexus. (*A benign epithelial tumor forming a rounded mass)

SYMPTOMS

Characteristic features of hydrocephalus in children include : cephalomegaly a thin, transparent scalp a bulging forehead with prominent fontanell a downward gaze.

Other clinical findings include: convulsions abnormal reflexes a slowed heartbeat and respiratory rate headache Vomiting Irritability Weakness problems with vision.

Blindness and continuing mental

deterioration from brain atrophy can result if treatment is not instituted.

CLASSIFICATIONA) COMMUNICATING B) NON- COMMUNICATING

A.COMMUNICATING HYDROCEPHALUS:

Also known as non-obstructive hydrocephalus It is caused by impaired cerebrospinal fluid reabsorption in the absence of any CSF-flow obstruction.

It has been theorized that this is due to

functional impairment of the arachnoids' granulations, which are located along the superior sagittal sinus and is the site of cerebrospinal fluid reabsorption back into the venous system.

Various neurologic conditions may result

in communicating hydrocephalus, including : subarachnoid/intraventricular hemorrhage, meningitis, Chiari malformation congenital absence of arachnoidal granulations (Pacchionis granulations).

Normal pressure hydrocephalus (NPH) :

- characterized by enlarged cerebral ventricles, with only intermittently elevated cerebrospinal fluid pressure. - The diagnosis of NPH can be established only with the help of continuous intraventricular pressure recordings (over 24 hours or even longer.

- Dynamic compliance studies may be also helpful. Altered compliance (elasticity) of the ventricular walls, as well as increased viscosity of the cerebrospinal fluid, may play a role in the pathogenesis of normal pressure hydrocephalus.

B.NON-COMMUNICATING Also known as obstructive hydrocephalus: cause by a CSF flow obstruction

( either due to external compression or intraventricular mass lesions.

Foramen of Monro obstruction may lead

to dilation of one or, if large enough (e.g., in colloid cyst), both lateral ventricles.

The aqueduct of Sylvius, normally

narrow to begin with, may be obstructed by a number of genetically or acquired lesions .

(e.g., atresia, ependymitis, hemorrhage,

tumor) and lead to dilatation of both lateral ventricles as well as the third ventricle.

Fourth ventricle obstruction will lead to

dilatation of the aqueduct as well as the lateral and third ventricles. Magendie may be obstructed due to congenital failure of opening (e.g., Dandy-Walker malformation) brainstem may also be obstructed due to inflammatory or hemorrhagic fibrosing meningitis, leading to widespread dilatation, including the fourth ventricle.

The foramina of Luschka and foramen of

The subarachnoid space surrounding the

CONGENITAL

The cranial bones fuse by the end of the third year of life. For head enlargement to occur, hydrocephalus must occur before then. The causes are usually genetic but can also be acquired and usually occur within the first few months of life, which include :

1 ) intraventricular matrix hemorrhages in premature infants 2) infections

3) type II Arnold-Chiari malformation 4) aqueduct atresia and stenosis, and 5) Dandy-Walker malformation.

In newborns and toddlers with

hydrocephalus, the head circumference is enlarged rapidly. Since the skull bones have not yet firmly

joined together, bulging, firm anterior and posterior fontanel's may be present even when the patient is in an upright position.

The infant exhibits fretfulness, poor feeding, and frequent vomiting. As the hydrocephalus progresses, torpor sets in, and the infant shows lack of interest in his surroundings. Later on, the upper eyelids become retracted and the eyes are turned downwards (due to hydrocephalic pressure on the `mesencephalic tegmentum and paralysis of upward gaze).

Movements become weak and the arms may become tremulous.

Papilledema is absent but there may be

reduction of vision. The head becomes so enlarged that the

child may eventually be bedridden.

About 80-90% of fetuses or newborn

infants with spina bifidaoften associated with meningocele or myelomeningocele develop hydrocephalus.

ACQUIRED as a consequence of CNS infections, meningitis, brain tumors, head trauma, intracranial hemorrhage (subarachnoid or intraparenchymal) and is usually extremely painful.

PATHOPHYSIOLOGY

The primary site of CSF formation is believed to be the choroid plexusus of the lateral ventricles. CSF flows from the lateral ventricles through the foramen of Monro to the third ventricle, then through the aqueduct of Sylvius into the fourth ventricle through the foramen of Luschka and the midline foramen of Magendie into the cisterna magna. From there it flows to the cerebral and cerebellar subarachnoid spaces where it is absorped.

Causes of Hydrocephalus are varied but

result in either impaired absorption of CSF within the arachnoid space (formerly referred to as communicating hydrocephalus) or obstruction to the flow of CSF through the ventricular system (formerly referred as noncommunicating hydrocephalus

Most cases of obstruction are the result of

developmental malformations; other causes include :

neoplasm infection and trauma Obstruction to the normal flow

can occur at any point in the CSF pathway, which produces increased pressure and dilation of the pathways proximal to the site of obstruction.

Impaired absorption can result from meningitis prenatal maternal infections

:

meningeal malignancy (secondary to

leukemia or lymphoma) an arachnoid cyst tuberculosis.

CLINICAL MANIFESTATIONS

Abnormal rate of head growth Bulging fontanelle Tense anterior fontanelle (often bulging and nonpulsatile) Dilated scalp veins Macewens sign (cracked pot) Frontal bossing Setting sun sign Sluggish and unequal pupils Irritability and lethargy with varying LOC Abnormal infantile reflexes Possible cranial nerve damage

Manifestations in children include: possible signs of increased ICP - which include headache on awakening with improvement following emesis, Papilledema Strabismus Ataxia Irritability Lethargy Apathy confusion.

LABORATORY AND DIAGNOSTIC TEST1 ) A prenatal diagnosis - Level II ultrasonography of the fetus. *** (Transuterine placement of ventriculoamniotic shunts during late pregnancy is still being developed as a treatment modality).

2 ) CT scan - postnatal. 3) MRI - can be used if a complex lesion is suspected.

TREATMENT Surgical correction is the

only treatment

for hydrocephalus.

consists of insertion of a ventriculoperitoneal shunt - which transports excess fluid from the lateral ventricle into the peritoneal cavity.

A less common procedure : insertion of a ventriculoatrial shunt

- which drains fluid from th