Hydrocephalus Clinical Presentation

Clinical features of hydrocephalus are influenced by the following:

• Patient's age

• Cause

• Location of obstruction

• Duration

• Rapidity of onset

Symptoms in infants include the following:

• Poor feeding

• Irritability

• Reduced activity

• Vomiting

Symptoms in children include the following:

• Slowing of mental capacity

• Headaches (initially in the morning) that are more significant than in infants because of skull rigidity

• Neck pain suggesting tonsillar herniation

• Vomiting, more significant in the morning

• Blurred vision: This is a consequence of papilledema and later of optic atrophy

• Double vision: This is related to unilateral or bilateral sixth nerve palsy

• Stunted growth and sexual maturation from third ventricle dilatation: This can lead to obesity and to precocious puberty or delayed onset of puberty.

• Difficulty in walking secondary to spasticity: This affects the lower limbs preferentially because the periventricular pyramidal tract is stretched by the hydrocephalus.

• Drowsiness

Symptoms in adults include the following:

• Cognitive deterioration: This can be confused with other types of dementia in the elderly.

• Headaches: These are more prominent in the morning because cerebrospinal fluid (CSF) is resorbed less efficiently in the recumbent position. This can be relieved by sitting up. As the condition progresses, headaches become severe and continuous. Headache is rarely if ever present in normal pressure hydrocephalus (NPH).

• Neck pain: If present, neck pain may indicate protrusion of cerebellar tonsils into the foramen magnum.

• Nausea that is not exacerbated by head movements

• Vomiting: Sometimes explosive, vomiting is more significant in the morning.

• Blurred vision (and episodes of "graying out"): These may suggest serious optic nerve compromise, which should be treated as an emergency.

• Double vision (horizontal diplopia) from sixth nerve palsy

• Difficulty in walking

• Drowsiness

• Incontinence (urinary first, fecal later if condition remains untreated): This indicates significant destruction of frontal lobes and advanced disease.

Symptoms of NPH include the following:

• Gait disturbance is usually the first symptom and may precede other symptoms by months or years. Magnetic gait is used to emphasize the tendency of the feet to remain "stuck to the floor" despite patients’ best efforts to move them.

• Dementia should be a late finding in pure (shunt-responsive) NPH. It presents as an impairment of recent memory or as a "slowing of thinking." Spontaneity and initiative are decreased. The degree can vary from patient to patient.

• Urinary incontinence may present as urgency, frequency, or a diminished awareness of the need to urinate.

• Other symptoms that can occur include personality changes and Parkinsonism. Seizures are extremely rare and should prompt consideration for an alternative diagnosis.

Physical findings in infants include the following:

• Head enlargement: Head circumference is at or above the 98^th percentile for age. or an increase rapidly across percentiles on the head growth curve.

• Dysjunction of sutures: This can be seen or palpated.

• Dilated scalp veins: The scalp is thin and shiny with easily visible veins.

• Tense fontanelle: The anterior fontanelle in infants who are held erect and are not crying may be excessively tense.

• Setting-sun sign: In infants, it is characteristic of increased intracranial pressure (ICP). Ocular globes are deviated downward, the upper lids are retracted, and the white sclerae may be visible above the iris.

• Increased limb tone: Spasticity preferentially affects the lower limbs. The cause is stretching of the periventricular pyramidal tract fibers by hydrocephalus.

Physical findings in children include the following:

• Papilledema: If the raised ICP is not treated, this can lead to optic atrophy and vision loss. The absence of papilledema does not rule out increased intracranial pressure, since it does not develop acutely.

• Failure of upward gaze: This is due to pressure on the tectal plate through the suprapineal recess. The limitation of upward gaze is of supranuclear origin. When the pressure is severe, other elements of the dorsal midbrain syndrome (ie, Parinaud syndrome) may be observed, such as light-near dissociation, convergence-retraction nystagmus, and eyelid retraction (Collier sign).

• Macewen sign: A "cracked pot" sound is noted on percussion of the head.

• Unsteady gait: This is related to spasticity in the lower extremities.

• Large head: Sutures are closed, but chronic increased ICP will lead to progressive macrocephaly.

• Unilateral or bilateral sixth nerve palsy is secondary to increased ICP. Children with ventriculoperitoneal (VP) shunts may be more likely to have congenital esotropia. ^[11]

Physical findings in adults include the following:

• Papilledema: If raised ICP is not treated, it leads to optic atrophy.

• Failure of upward gaze and of accommodation indicates pressure on the tectal plate. The full Parinaud syndrome is rare.

• Unsteady gait is related to truncal and limb ataxia. Spasticity in legs also causes gait difficulty.

• Large head (macrocephaly): The head may have been large since childhood. 

• Unilateral or bilateral sixth nerve palsy is secondary to increased ICP. Children with ventricular-peritoneal shunts may be more likely to have congenital esotropia. 

The following are physical findings found in NPH:

• Muscle strength is usually normal. No sensory loss is noted.

• Reflexes may be increased, and the Babinski response may be found in one or both feet. These findings should prompt search for vascular risk factors (causing associated brain microangiopathy or vascular Parkinsonism), which are common in NPH patients.

• Difficulty in walking varies from mild imbalance to inability to walk or to stand. The classic gait impairment consists of short steps, wide base, externally rotated feet, and lack of festination (hastening of cadence with progressively shortening stride length, a hallmark of the gait impairment of Parkinson disease). These abnormalities may progress to the point of apraxia. Patients may not know how to take steps despite preservation of other learned motor tasks.

• Frontal release signs such as sucking and grasping reflexes appear in late stages.

Congenital causes in infants and children include the following: ^[8]

• Brainstem malformation causing stenosis of the aqueduct of Sylvius: This is responsible for 10% of all cases of hydrocephalus in newborns.

• Dandy-Walker malformation: This affects 2-4% of newborns with hydrocephalus.

• Arnold-Chiari malformation type 1 and type 2

• Agenesis of the foramen of Monro

• Congenital toxoplasmosis

• Bickers-Adams syndrome: This is an X-linked hydrocephalus accounting for 7% of cases in males. It is characterized by stenosis of the aqueduct of Sylvius, severe intellectual disability, and in 50% by an adduction-flexion deformity of the thumb.

Acquired causes in infants and children include the following:

• Mass lesions: Mass lesions account for 20% of all cases of hydrocephalus in children. These are usually tumors (eg, medulloblastoma, astrocytoma), but cysts, abscesses, or hematoma also can be the cause. ^[12]

• Hemorrhage: Intraventricular hemorrhage can be related to prematurity, head injury, or rupture of a vascular malformation.

• Infections: Meningitis (especially bacterial) and, in some geographic areas, cysticercosis can cause hydrocephalus.

• Increased venous sinus pressure: This can be related to achondroplasia, some craniostenoses, or venous thrombosis.

• Iatrogenic: Hypervitaminosis A, by increasing secretion of CSF or by increasing permeability of the blood-brain barrier, can lead to hydrocephalus. As a caveat, hypervitaminosis A is a more common cause of idiopathic intracranial hypertension, a disorder with increased CSF pressure but small rather than large ventricles.

• Idiopathic

Causes of hydrocephalus in adults include:

• Subarachnoid hemorrhage (SAH) causes one third of these cases by blocking the arachnoid villi and limiting resorption of CSF. However, communication between ventricles and subarachnoid space is preserved. ^[13]

• Idiopathic hydrocephalus represents one third of cases of adult hydrocephalus.

• Head injury, through the same mechanism as SAH, can result in hydrocephalus.

• Tumors can cause blockage anywhere along the CSF pathways. The most frequent tumors associated with hydrocephalus are ependymoma, subependymal giant cell astrocytoma, choroid plexus papilloma, craniopharyngioma, pituitary adenoma, hypothalamic or optic nerve glioma, hamartoma, and metastatic tumors.

• Prior posterior fossa surgery may cause hydrocephalus by blocking normal pathways of CSF flow.

• Congenital aqueductal stenosis causes hydrocephalus but may not be symptomatic until adulthood. Special care should be taken when attributing new neurological deficits to congenital hydrocephalus, as its treatment by shunting may not correct these deficits.

• Meningitis, especially bacterial, may cause hydrocephalus in adults.

• All causes of hydrocephalus described in infants and children are present in adults who have had congenital or childhood-acquired hydrocephalus.

Causes of NPH may include the following (Most cases are idiopathic and are probably related to a deficiency of arachnoid granulations.):

• SAH

• Head trauma

• Meningitis