Signs and Symptoms of Hydrocephalus

The signs and symptoms of hydrocephalus in infants and children vary depending on their age, the degree of hydrocephalus at presentation, the primary etiology, and the time over which the hydrocephalus develops. Because of the plasticity of the infant brain and the ability of the cranium to expand, ventriculomegaly can progress without obvious signs of increased intracranial pressure. In premature infants, in which hydrocephalus is caused predominately by an IVH, there is a general correlation between the severity of hemorrhage and the degree of hydrocephalus. Infants with PHH may have minimal symptoms, or may exhibit increasing spells of apnea and bradycardia. They may also have hypotonia, sunsetting eyes, ophthalmoplegia and seizures. As the ventriculomegaly progresses, the fontanel will bulge, become tense and nonpulsatile, and the cranial sutures become splayed. In a healthy premature infant, the head circumference generally increases about 1 cm a week. In premature infants with progressive ventriculomegaly, the head circumference may increase more rapidly than normal (when charted on the head growth chart), but may not accurately reflect the rate of increase in ventricular size.

Table : Signs and symptoms of hydrocephalus in children
Premature infants	Full-term infants	Toddlers and older
Apnea	Macrocephaly	Headache
Bradycardia	Rapid head growth	Nausea
Hypotonia	Decreased feeding	Vomiting
Acidosis	Increased drowsiness	Irritability
Seizures	Tense fontanel	Lethargy
Rapid head growth	Vomiting	Delayed development
Tense fontanel	Distended scalp veins	Decreased school performance
Splayed cranial sutures	Splayed cranial sutures	Behavioral disturbance
Vomiting	Poor head control	Papilledema
Sunsetting eyes	Parinaud’s sign	Parinaud’s sign
	Sunsetting eyes	Sunsetting eyes
	Frontal bossing	Bradycardia
		Hypertension
		Irregular breathing patterns

Posthemorrhagic Hydrocephalus of Prematurity

The most common cause of hydrocephalus in the premature infant is a germinal matrix hemorrhage. The germinal matrix is a very vascular area in the fetal brain, in the subependymal region located at the level of the foramen of Monro. It is from the very thinwalled germinal matrix vessels that the bleeding is thought to occur in preterm infants. Bleeding can spread, most often to the adjacent ventricles and into the surrounding parenchyma. The germinal matrix gradually involutes after 34 weeks gestation and nearly disappears by 40 weeks. A grading system has been devised to describe the severity of the bleeding – grades I–IV.

Premature infants of less than 34 weeks gestation with very low birth weight (<1500 g) are at greatest risk for developing IVH. With current management, 20% of these preterm infants will develop an IVH. The risk of developing posthemorrhagic hydrocephalus (PHH) is related directly to the extent of the hemorrhage. Hydrocephalus develops in 20–74% of infants with IVH [3]. Infants with a grade I or II bleed do not have hydrocephalus by definition; 55% of infants with a grade III hemorrhage and 80% of those with a grade IV bleed develop hydrocephalus. PHH may develop as a result of the accumulation of blood and hemorrhagic debris within the ventricles and subarachnoid spaces. Obstruction of the aqueduct of Sylvius or foramen of Monro may occur. The breakdown of blood may also render the arachnoid villi unable to reabsorb the CSF. Multiloculated hydrocephalus may occur after IVH due to ventriculitis. Ventricular septations develop causing isolated compartments of fluid within the ventricles.

Many premature infants require surgical intervention to treat the hydrocephalus until it is resolved. About 20–30% will require permanent shunting.

Classifications of Types of Hydrocephalus

Hydrocephalus is subdivided into several different categories. Communicating and noncommunicating are the most common categories. These terms were previously used interchangeably with obstructive and nonobstructive. The latter terms have fallen from use, as it is believed that in almost all cases of hydrocephalus there is some obstruction of CSF reabsorption; the exception is the rare state of overproduction of CSF. Hydrocephalus is also subdivided into congenital versus acquired, and internal versus external (see table). Other categories include normal pressure hydrocephalus and ex vacuo hydrocephalus.

Table. Classifications of hydrocephalus

Communicating

Congenital Achondroplasia Arachnoid cyst Dandy-Walker malformation Associated with craniofacial syndromes Acquired Posthemorrhagic: intraventricular or subarachnoid Choroid plexus papilloma or choroid plexus carcinoma Venous obstruction as in superior vena cava syndrome Postinfectious

Noncommunicating

Congenital Aqueductal stenosis Congenital lesions (vein of Galen malformation, congenital tumors) Arachnoid cyst Chiari malformations either withor without myelomeningocele X-linked hydrocephalus Dandy-Walker malformation Acquired Aqueductal gliosis (posthemorrhagic or postinfectious) Space-occupying lesions such as tumors or cysts Head injuries

Hydrocephalus : History of Hydrocephalus

Hydrocephalus is a condition resulting from an imbalance between the production and absorption of cerebral spinal fluid (CSF). This imbalance results in an increased volume of spinal fluid, dilation of the ventricular system, and often increased intracranial pressure. Hydrocephalus can be acute and occur over hours or days. It may also be chronic and occur over months or years. Hydrocephalus can occur as an isolated condition or one associated with numerous other neurological conditions and diseases.

The term hydrocephalus is derived from the Greek words “hydro” meaning water, and “cephalus” meaning head. The description and treatment of hydrocephalus dates back to the era of Hippocrates and Galen. Galen (AD 130–200) identified the ventricles. He believed that the soul was purified through the pituitary gland, and that waste was discharged via the nose as “pituita.” During the Renaissance, Vesalius (1514–1564) described the ventricular system in his original text on human anatomy. A century later, Franciscus Sylvius (1614–1672) described the cerebral aqueduct. Morgagni (1682–1771) described the pathology of hydrocephalus, and Monro (1733–1817) named the intraventricular foramen. In 1786, Whytt distinguished the internal and external hydrocephalus.

Early treatments included bleeding, purging, surgical release of the fluid, puncturing the ventricles to drain the fluid, injection of iodine or potassium hydriodate into the ventricles, binding of the head, application of a plaster of herbs to the head, application cold wraps to the head, lumbar puncture, and diuretics. Confusion about hydrocephalus persisted into the 1800s. It was thought to be caused by fevers, rheumatism, pulmonary consumption, and worms; however, treatment did not change.

The earliest attempts at surgery occurred during the late 1800s. The first shunts diverted CSF from the ventricles to the subcutaneous or subdural spaces. During the early 1900s, other surgical procedures were attempted to treat the condition. These procedures included surgical removal of the choroid plexus, diversion of spinal fluid through a third ventriculostomy, and continued attempts at shunting, including attempts to shunt into the vascular space. Most of these patients did poorly, and either suffered the consequences of prolonged increased intracranial pressure or died. Many institutions cared for these disabled children with very large heads, small bodies, and severe mental retardation.

Modern shunting procedures began in the 1950s with the introduction of the antireflux valve. The first valves developed by Nulson and Spitz in 1952, used a spring and steel ball valve. Holter then developed the first slit valve. He was particularly interested in shunt development, as he had a son with a myelomeningocele and hydrocephalus. These first modernized shunts diverted CSF from the ventricles to the right atrium of the heart. The ventricular-to-peritoneal shunt became the preferred shunt in the 1970s because it allowed for the child to grow, and not outgrow the length of the shunt tubing. This has remained the preferred shunt procedure among modern neurosurgeons. Neurosurgeons have also placed shunts leading from the ventricle to the pleural space, gall bladder, ureter, or fallopian tube if the abdominal cavity is not an appropriate place to terminate the shunt. Numerous improvements in shunt hardware have occurred in the last four decades.

A genetic understanding of hydrocephalus and the diseases associated with hydrocephalus has occurred in the last decade. Such knowledge of genetics has allowed for improved prenatal diagnosis and genetic counseling.

Growth and Developmental Tasks by Age - Developmental Assessment

Knowledge of human growth parameters and normal developmental landmarks is critical to the assessment of each age group. Growth is defined as changes in the values given certain measurements of maturity; where as development may encompass other aspects of differentiation of form or function, including those emotional or social changes preeminently shaped by interaction with the environment.

Serial measurements can indicate the normal or abnormal dynamics of the child’s growth. One key growth measurement important to the neurological assessment of the child is the head circumference. The measurement is taken around the most prominent frontal and occipital bones which offer the maximal circumference. How rapidly the head circumference accelerates or decelerates away from the percentile curve can determine whether the underlying cause of the growth change is more benign or serious. An example of a benign finding is the presence of extra-axial fluid collections of infancy, which often present with an accelerating head circumference. Generally, the infant with this finding is observed over time, but no intervention is warranted. On the other hand, an accelerating head circumference can also be a sign of increasing intracranial pressure in uncompensated hydrocephalus, which would require immediate evaluation and treatment.

Development is the essential distinguishing feature of pediatric nursing. Normal development is a function of the integrity and maturation of the nervous system. Only with a working knowledge of agerelated developmental standards can the examiner be sensitive to the deviations that indicate slight or early impairment of development and an abnormal neurological assessment. An abnormality in development from birth suggests an intrauterine or perinatal cause. Slowing of the rate of acquisition of skills later in infancy or childhood may imply an acquired abnormality of the nervous system. A loss of skills (regression) over time strongly suggests an underlying degenerative disease of the central nervous system.

Voluntary motor skills generally develop in a cephalocaudal and proximodistal progression, as it parallels the process of myelination. First the head, then the trunk, arms, hands, pelvis, legs, bowel, and bladder are brought under voluntary control. Early in life, motor activity is largely reflexive, and generalized movements predominate. Patterns emerge from the general to the specific; for example, a newborn’s totalbody response to a stimulus is contrasted with the older child, who responds through simply a smile or words. So, as the neuromuscular system matures, movement gradually becomes more purposeful and coordinated. The sequence of development is the same for all children, but the rate of development varies from child to child.

Finally, also important to a complete neurological exam is an assessment of the child’s cognitive and emotional development. These abilities impact directly on expectations of the child’s behavioral, social, and functional capabilities. The younger the child, the more developmental history is needed from the parents. Accurate identification of the child’s mastery of cognitive and emotional developmental milestones, as it relates to chronological age, is necessary for a comprehensive neurological assessment.