Hydrocephalus, also known as “water on the brain,” is a condition where there is an abnormal accumulation of cerebrospinal fluid (CSF) in the brain. This buildup of fluid causes increased pressure inside the skull which can lead to brain damage and other complications if left untreated. But when do doctors usually first identify and diagnose this condition in patients? Here is an overview of when hydrocephalus is often caught and formally diagnosed at different stages of life.
In Utero or at Birth
Hydrocephalus can sometimes be detected before birth during routine prenatal ultrasounds and tests. If enlarged ventricles or other abnormalities are seen, it may indicate fetal hydrocephalus. However, not all cases are caught prenatally. According to research, only about 1 in 4,000 pregnancies are complicated by hydrocephalus. It is one of the most common birth defects, occurring in approximately 1 out of every 500 births.
For infants born with significant hydrocephalus, the signs are usually apparent immediately or within the first few months of life. Rapidly increasing head circumference beyond normal growth curves is one of the hallmark symptoms. Babies’ fontanelles (soft spots) may be quite full and bulging. Early symptoms also often include downward casting of the eyes (also called “sunsetting”), irritability, sleepiness, vomiting, and seizures.
Pediatricians routinely measure head circumference at well-child visits, so marked enlargement generally leads to further evaluation. Diagnostic imaging tests like ultrasounds, CT scans, or MRIs can confirm ventricular enlargement and other abnormalities. Pediatric neurosurgeons or neurologists then make the definitive hydrocephalus diagnosis. Prompt diagnosis is essential in newborns because immediate treatment is required to prevent brain damage.
Childhood
Children who did not have noticeable hydrocephalus as infants can still develop the condition later in childhood. This is known as acquired hydrocephalus. It is often associated with events like infections (especially meningitis), head trauma, brain tumors or cysts, intracranial hemorrhage, or complications of prematurity.
The signs and symptoms in an older infant or child can include:
- Increasing head size
- Bulging fontanelles
- Irritability
- Vomiting
- Sleepiness or lethargy
- Seizures
- Headaches
- Delayed or abnormal motor development
- Loss of previously attained milestones
- Changes in vision or eye coordination
- Decline in academic performance
- Behavioral changes
Pediatricians monitor head growth at well-child visits. Significant enlargement or rapid acceleration in growth percentiles warrants further evaluation. Neuroimaging and potentially a referral to a pediatric neurologist or neurosurgeon are recommended if hydrocephalus is suspected.
On average, congenital hydrocephalus is diagnosed before age 2, while acquired childhood hydrocephalus is usually diagnosed between ages 5-10. However, the timing depends on multiple factors like the underlying cause, the rate of progression, and the specific symptoms manifested.
Adolescence
Rarely, hydrocephalus first arises in the adolescent years. The causes are usually similar to those associated with acquired hydrocephalus in younger children. For example, hydrocephalus can develop after traumatic brain injuries, CNS infections, intracranial hemorrhage, or as a complication of a brain tumor.
Adolescents are more likely to report symptoms like headaches, vision changes, nausea/vomiting, balance problems, cognitive decline, and emotional/behavioral issues associated with increased intracranial pressure. Since routine well-child visits and head circumference measurements are less frequent in this age group, patients and parents need to recognize potential red flags. If caught early, the treatment prognosis is often good.
Adulthood
The development of hydrocephalus most commonly occurs in infancy and childhood, but it can arise later in life as well. An estimated 375,000 adults have hydrocephalus in the United States. There are two main types seen in adults:
Congenital Hydrocephalus
Some individuals originally diagnosed with childhood hydrocephalus can experience a recurrence or worsening of symptoms in adulthood. This may be due to shunt failure or malfunction in those who had shunts placed earlier in life. Symptoms like headaches, cognitive changes, balance issues, incontinence, and vision problems can prompt affected individuals to seek medical attention leading to a hydrocephalus diagnosis.
Acquired Hydrocephalus
Hydrocephalus acquired in adulthood has numerous potential causes including:
- CNS infections like meningitis
- Head trauma
- Brain tumors or cysts
- Intracranial hemorrhages
- Normal pressure hydrocephalus (often idiopathic cause)
Adults may complain of symptoms like:
- Headaches
- Nausea/vomiting
- Gait instability or falls
- Cognitive impairment
- Urinary incontinence
- Personality changes
- Decline in memory and reasoning
- Psychosis
These kinds of changes should prompt urgent medical evaluation. Neuroimaging and assessment of CSF composition via lumbar puncture are used to aid diagnosis. If hydrocephalus is identified and treated in a timely manner, adults can still have good outcomes.
Seniors and the Elderly (65+ years old)
Hydrocephalus most often affects seniors in the form of normal pressure hydrocephalus (NPH), also sometimes called senile hydrocephalus. This gradually progressive disorder arises due to impaired absorption of CSF. Individuals typically develop symptoms in their 60s or 70s. The underlying cause is often unknown but may relate to prior conditions like subarachnoid hemorrhage, meningitis, head trauma, or complications of neurosurgery.
The classic triad of symptoms includes:
- Dementia
- Gait disturbance
- Urinary incontinence
Additional signs can include headache, psychomotor slowing, Parkinsonism, and vertigo. The development of these kinds of issues in the senior population should raise suspicion for NPH. Diagnosis is made based on clinical evaluation, neurocognitive testing, and radiologic findings. If addressed early, some patients experience symptom improvement after shunting procedures.
Conclusion
In summary, hydrocephalus can arise at any age from infancy through late adulthood. However, the peak incidence is among infants and young children. Pediatricians routinely monitor head growth, so conspicuous enlargement usually triggers further evaluation. Acquired hydrocephalus later in life may manifest with symptoms like headaches, balance problems, incontinence, and cognitive decline. Prompt diagnosis and treatment, regardless of a patient’s age, can help prevent complications and disability from this disorder characterized by excessive cerebrospinal fluid accumulation in the brain.