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Cerebrospinal fluid tap test in normal pressure hydrocephalus
Josephine Schena1, Harvey Burns2, Alexander Hayes2
1Neurosciences, Imperial College Healthcare NHS Trust, London, UK.
Practical Neurology
|June 12, 2026
Summary
Normal pressure hydrocephalus (NPH) diagnosis in older adults can be improved with cerebrospinal fluid (CSF) tap tests. These tests help identify patients who will benefit from CSF shunting surgery.
Area of Science:
- Neurology
- Neurosurgery
Background:
- Normal pressure hydrocephalus (NPH) presents with gait apraxia, cognitive impairment, and urinary incontinence in older adults.
- Differentiating NPH from normal aging is challenging due to overlapping symptoms and common communicating hydrocephalus.
Purpose of the Study:
- To describe the clinical practice of cerebrospinal fluid (CSF) tap tests for NPH.
- To highlight evidence-based nuances and common pitfalls in performing CSF tap tests for NPH.
Main Methods:
- Utilizing large-volume lumbar puncture (CSF tap test) to assess potential candidates for CSF shunting.
- Reviewing current evidence and practical considerations for NPH diagnosis.
Main Results:
- CSF tap tests are effective in identifying suitable candidates for CSF shunting.
- Neurologists require specific considerations for CSF tap tests beyond routine lumbar punctures.
Conclusions:
- CSF tap tests are a valuable tool in selecting patients for NPH treatment.
- Understanding the nuances and limitations of CSF tap tests is crucial for accurate NPH diagnosis.
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