Hydrocephalus and CSF Disorders
What is hydrocephalus
Hydrocephalus is a condition in which an excessive amount of cerebrospinal fluid accumulates within the ventricles of the brain.
This fluid is normally produced within the brain, circulates around the brain and spinal cord, and is then reabsorbed.
When the balance between its production, circulation and absorption is disrupted, the fluid accumulates, the ventricles enlarge, and pressure is exerted on the brain tissue.
Acute hydrocephalus is an emergency that requires immediate neurosurgical intervention.
Types of hydrocephalus
Hydrocephalus is divided into two main categories depending on the cause of the disturbance.
Obstructive, or non-communicating, hydrocephalus: there is a mechanical blockage to the flow of fluid within the ventricular system, often due to a tumour, haemorrhage or congenital stenosis.
Communicating hydrocephalus: there is no mechanical obstruction, but the absorption of the fluid is impaired.
Depending on the time of onset, hydrocephalus may also be congenital, when it is already present at birth because of anatomical abnormalities, or acquired, when it appears later in life.
General causes of hydrocephalus
Hydrocephalus may be caused by congenital anatomical abnormalities present from birth, by tumours that obstruct the flow of fluid, by intracranial haemorrhage, by infections of the central nervous system such as meningitis, as well as by head injury.
Symptoms by age
The symptoms of hydrocephalus vary significantly according to the patient’s age.
In infants, whose skull bones have not yet fully fused, hydrocephalus may cause a rapid increase in head circumference, vomiting, drowsiness and a characteristic downward deviation of the eyes.
In older children and adults, symptoms usually include severe headache, double vision, balance problems, as well as changes in personality or mood.
In older people, hydrocephalus often presents in a different, more insidious way, known as normal pressure hydrocephalus, which is described in more detail below.
Normal pressure hydrocephalus
Normal pressure hydrocephalus, internationally known as Normal Pressure Hydrocephalus (NPH), is a particular form of hydrocephalus that occurs mainly in people over the age of 60. It is so called because intracranial pressure remains within the upper normal range, as the fluid accumulates very slowly and gradually, allowing the brain to adapt progressively without the pressure appearing elevated on measurements.
NPH often goes unnoticed or is confused with Alzheimer’s dementia, as it shares the classic triad of symptoms: gait disturbance with an unsteady, broad-based gait (“magnetic” gait), usually the first symptom to appear; cognitive decline with memory impairment; and urinary incontinence, which usually follows later. It is particularly associated with falls and subdural haematomas in this age group.
The important difference from dementia is that, when the diagnosis is confirmed by a cerebrospinal fluid drainage test and is followed promptly by the appropriate surgical treatment, symptoms can improve to a large extent, usually first in bladder function, then in gait, and lastly in memory.
Diagnosis
The diagnosis of hydrocephalus is initially based on a detailed clinical and neurological examination and is confirmed with imaging, usually MRI or CT of the brain, which demonstrates enlargement of the ventricles.
In cases where normal pressure hydrocephalus is suspected, the diagnostic work-up is complemented by neuropsychological assessment, gait assessment, and the drainage test described above.
Treatment
The main treatment for hydrocephalus is surgical diversion of the excess fluid. The most common method is insertion of a ventriculoperitoneal shunt, a thin catheter with a valve that diverts the fluid from the ventricles of the brain to the abdominal cavity.
In selected cases of obstructive hydrocephalus, particularly when the obstruction is located at a specific point in the ventricular system, endoscopic third ventriculostomy may be preferred, a technique that creates a new pathway for fluid flow without the need for a permanent valve.
Dr Nektarios Mazarakis selects the treatment technique on an individual basis, according to the cause, the site of obstruction and the patient’s age.
Prognosis
The prognosis of hydrocephalus depends on the cause, the patient’s age, and the timeliness of diagnosis and treatment. In normal pressure hydrocephalus, early shunt placement is associated with a significant improvement in quality of life, whereas delay in diagnosis may lead to symptoms that are less reversible, particularly in cognitive function.
Book an Appointment
Dr Nektarios Mazarakis sees patients with hydrocephalus and cerebrospinal fluid disorders at his clinics in Athens and Thessaloniki, across all age groups, from infants to older adults.