What is hydrocephalus?

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From the Guidelines

Hydrocephalus is a condition characterized by an abnormal buildup of cerebrospinal fluid (CSF) within the ventricles of the brain, which can lead to increased intracranial pressure, brain damage, and a range of neurological symptoms. This condition can occur at any age, but is most common in infants and older adults. The development of hydrocephalus is often due to an overproduction of CSF, a blockage preventing normal CSF flow, or inadequate absorption of CSF into the bloodstream [ 1 ]. Symptoms of hydrocephalus vary by age, but commonly include headache, nausea, vomiting, blurred vision, cognitive impairment, difficulty walking, and in infants, an abnormally large head, bulging fontanelle, and irritability.

Causes and Risk Factors

The causes of hydrocephalus can be divided into two main categories: obstructive and non-obstructive. Obstructive hydrocephalus occurs when there is a blockage in the flow of CSF, while non-obstructive hydrocephalus occurs when there is an imbalance between CSF production and absorption [ 1 ]. Risk factors for developing hydrocephalus include age, with infants and older adults being at higher risk, as well as certain medical conditions, such as cerebral hemorrhage, meningitis, and brain tumors.

Diagnosis and Treatment

Diagnosis of hydrocephalus typically involves a combination of physical examination, medical history, and imaging studies, such as MRI or CT scans [ 1 ]. Treatment of hydrocephalus usually involves surgical placement of a shunt system to divert excess CSF from the brain to another part of the body where it can be absorbed, or an endoscopic third ventriculostomy (ETV) procedure that creates an alternative pathway for CSF flow [ 1 ]. In patients with aneurysmal subarachnoid hemorrhage (aSAH) and acute symptomatic hydrocephalus, urgent CSF diversion is recommended to improve neurological outcome [ 1 ].

Outcomes and Prognosis

Without treatment, progressive hydrocephalus can lead to brain damage, disability, or death, making early diagnosis and intervention crucial for better outcomes [ 1 ]. The prognosis for hydrocephalus varies depending on the underlying cause, the severity of symptoms, and the effectiveness of treatment. Permanent CSF diversion has been shown to improve neurological outcome after aSAH [ 1 ]. Overall, prompt recognition and treatment of hydrocephalus are essential to prevent long-term neurological damage and improve quality of life.

From the Research

Definition of Hydrocephalus

  • Hydrocephalus is an over-accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain 2
  • It can affect cognitive function, vision, appetite, and cranial nerve function 2
  • Left untreated, hydrocephalus can result in death 2

Causes and Treatment

  • Hydrocephalus can be caused by various factors, including congenital lesions, tumoral lesions, and choroid plexus hyperplasia 3, 4
  • The current treatment for hydrocephalus uses ventriculoperitoneal (VP) shunts with valves to redirect CSF from the ventricles into the peritoneum 2
  • Alternative treatments, such as lumboperitoneal shunts, are also available and have been shown to be safe and effective in some cases 5

Complications and Failure Rates

  • Shunt technology is limited by a number of complications, including infection, shunt obstruction, disconnection, and overdrainage or underdrainage of CSF 2
  • The failure rate of ventriculoperitoneal shunts is high, with some studies reporting failure rates of up to 33.9% 3
  • Perioperative CSF protein levels have been shown to be associated with shunt failure, with higher levels of protein potentially leading to increased risk of failure 6

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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