Overview

Hydrocephalus is a disorder caused by an abnormal accumulation of cerebrospinal fluid (CSF) in the brain. The pressure exerted on the brain by the liquid damages it, and can be fatal if left untreated.¹ Hydrocephalus can be present at birth, or develop later. 

Cerebrospinal fluid is a clear fluid that acts as cushioning to protect the brain and spine. The body reabsorbs the same amount of CSF that it produces, so when there is an excess, the body cannot reabsorb it. It prevents proper functioning of the brain and causes brain damage or death. Non-communicating hydrocephalus occurs due to a blocked flow of CSF through the brain. 

Understanding non-communicating hydrocephalus 

Non-communicating hydrocephalus or obstructive hydrocephalus is caused when the CSF cannot flow along the narrow pathways connecting the ventricles. Communicating hydrocephalus is similar, but the flow of CSF is blocked after it exits the ventricles.² 

Who is affected by hydrocephalus?

Hydrocephalus can occur immediately after birth or in adult life after an injury or accident. An estimated report suggests that one to two of every 1000 babies are affected at birth by hydrocephalus.¹

Babies can be born with hydrocephalus or develop symptoms shortly after birth. It is caused by:

• An inherited genetic abnormality that blocks the flow of CSF
• A developmental disorder associated with defects of the brain, spine, or spinal cord
• Complications due to premature birth
• Infection during pregnancy that can cause inflammation of the fetal brain tissue

However, hydrocephalus can occur at any age due to specific factors increasing the risk of development, such as: 

• Brain or spinal cord tumour 
• Infection of the central nervous system
• A brain bleed caused by injury or stroke

Symptoms and treatment 

What are the symptoms of hydrocephalus?

The symptoms of hydrocephalus vary depending on the age group of the person. They present differently on an individual basis. Symptoms in infants can be:

• An abnormally large head that increases in size quickly
• A bulge around the soft spot of their head
• Sickness
• Struggling with sucking or feeding
• Tired and irritable 
• Sunsetting eyes that are stuck pointing downwards¹
• Seizures

Symptoms in older children and adults may include:

• Headaches
• Poor vision, blurred or double
• Loss of coordination and balance
• Problems with speech
• The decline in bladder control
• Tiredness paired with difficulty staying awake or waking up
• Decline in memory and cognitive ability 

Symptoms in older adults may include:

• Loss of mobility and coordination
• Incontinence 
• A progressive decline in mental ability
• Dementia

Hydrocephalus is undiagnosed in older patients due to the symptoms being similar to conditions like Alzheimer’s. Hydrocephalus must be diagnosed correctly, as the symptoms can be treated, unlike Alzheimer’s.

How is non-communicating hydrocephalus diagnosed?

Clinical neurological examination and brain imaging scans help to diagnose hydrocephalus. Other tests that depend on age, symptoms and known or suspected underlying brain and spinal cord conditions.

The neurological exam will involve tests to determine:

• Muscle strength 
• Coordination, balance, and reflexes
• Vision and hearing
• Cognitive ability

Further tests are required to diagnose hydrocephalus and rule out other conditions. They are:

• MRI scan (shows possible swelling of ventricles, helps to analyse CSF flow and surrounding brain tissue)
• CT scan (shows if there is an obstruction or swelling of ventricles in the brain)
• Ultrasound 
• Spinal tap/Lumbar puncture (estimates the pressure of the CSF and allows for CSF analysis)
• Intracranial pressure monitoring (determines the pressure and swelling within the brain)
• Fundoscopic examination (examines the back of the eye socket for swelling)

What is the impact of non-communicating hydrocephalus if left untreated?

Hydrocephalus can be life-altering and fatal if left untreated. CSF is responsible for acting as a shock absorber by cushioning the brain. It also carries nutrients to the brain, removes waste, and regulates the internal pressure of the brain.³ When someone experiences an injury or damage to their brain, the ventricles will become large and swollen as the amount of CSF increases, causing the pressure inside the brain to rise. 

Hydrocephalus is a chronic disorder, that lasts a long time or may flare up recurrently. The symptoms of hydrocephalus, if detected early can be treated Patients survive with little limitation.⁴

What is the treatment for non-communicating hydrocephalus?

Surgical treatment is necessary for the reduction of symptoms and morbidity of hydrocephalus, with the gold standard procedure being the placement of a shunt, which appropriately directs the flow of CSF out of the brain.⁵ There is a second option known as the Endoscopic Third Ventriculostomy (ETV) which improves the flow of CSF out of the brain via a small hole at the bottom of one of the enlarged ventricles. 

The placement of a shunt requires frequent checkups and monitoring, and they may need to be replaced multiple times throughout the lifetime. The success of this surgery varies from person to person, but most recover and experience a good quality of life with few limitations after treatment.⁴

There are supportive therapies that may be helpful for children, such as: 

• Occupational therapist
• Developmental therapist
• Special education teachers
• Mental health providers
• Social workers

Adults may benefit from similar support, including specialists in dementia care.

Challenges and future direction of hydrocephalus treatment 

Surgical treatment is almost exclusively the only method of treatment for hydrocephalus, which often requires repeated surgeries to replace broken shunts throughout a lifetime. 

In the last 100 years, there has been little progress in the non-surgical treatment for hydrocephalus. However, there has been a recent increase in the emergence of pharmaceutical (medication), stem cell and gene therapy research. Further research and trials of these therapies would increase the standard of care for individuals with hydrocephalus, providing them with a better quality of life. 

Summary

Hydrocephalus is a disorder where inflammation of the ventricles in the brain can block the movement and drainage of cerebrospinal fluid, causing intense pressure to build up within the brain. Hydrocephalus can occur immediately after birth or later in life due to injury or illness. The symptoms of hydrocephalus are threatening if left untreated, potentially causing irreversible brain damage or death. These symptoms reduce mobility, coordination, speech, vision, memory and cognitive ability.

Hydrocephalus occurs due to genetic abnormalities of the brain or spinal cord, birth complications, infection, tumours of the brain or spinal cord, or a brain bleed, which can all cause swelling and enlargement of the ventricles in the brain. 

Neurological examination, which investigates your muscle strength, balance, coordination, reflexes, vision, hearing and memory, helps to diagnose it. Scans (MRI or CT) of your brain follow the neurological examination to determine swelling and pressure in the brain. Accurate diagnosis is important, as some symptoms of hydrocephalus can be mistaken for Alzheimer’s disease, which is an untreatable condition, unlike hydrocephalus, that requires surgical intervention. 

Treatment of hydrocephalus is surgical, with the most common procedure being the placement of a shunt. A shunt helps to direct the CSF out of the brain. This procedure requires monitoring and frequent checkups as it is common for the shunt to become non-functional and then need a replacement. Currently, f non-surgical interventions to alleviate the symptoms of hydrocephalus are not available. However, there has been an increase in research into drug-based treatment and other biological therapies.