Cerebrospinal Fluid Examination

What is a cerebrospinal fluid examination in animals?

The cerebrospinal fluid (CSF) examination is a diagnostic procedure to detect diseases or damage to the central nervous system (CNS) in animals. Cerebrospinal fluid is collected and examined for pathological changes. The procedure allows for the diagnosis of inflammation, infections, tumours, and other neurological conditions.

How is a cerebrospinal fluid examination performed in animals?

1. Preparation and anaesthesia:
   • In small animals (dogs, cats), collection is performed under general anaesthesia.
   • Large animals (horses, ruminants) typically receive local anaesthesia and a sedative. General anaesthesia can also be used, particularly for collection between the skull and the upper cervical vertebrae.
2. Liquor sampling:
   • Small animals: A spinal needle is inserted into the spinal canal at the junction between the occipital bone and the upper cervical vertebra to collect CSF. Alternatively, collection can be performed between the lumbar vertebrae, although the risk of blood contamination is higher.
   • Livestock: The cerebrospinal fluid is preferably collected in the lumbar region under local anaesthesia. Collection between the skull and the upper cervical vertebrae is also possible.
3. Examination of the liquor:
   • Freshly collected CSF samples are examined immediately.
   • Parameters such as colour, turbidity, coagulation, protein and sugar content, as well as the number of white blood cells and other cells, are checked.
   • Detection of pathogens such as bacteria, viruses, parasites, protozoa and fungi.

When is a CSF examination used in animals?

The CSF examination is particularly suitable for diagnosing diseases and damage to the central nervous system (CNS). It is used in cases of:

• Tumours of the brain and spinal cord
• Damage to the brain or spinal cord following accidents
• Infections caused by bacteria, viruses (e.g. distemper in dogs), parasites, protozoa (e.g. toxoplasmosis in cats) and fungi (e.g. cryptococcosis, especially in cats)
• Inflammation of the CNS that is not always detectable in blood tests
• Liver diseases that can affect the CNS
• Monitoring treatment success in neurological diseases

What risks are associated with a CSF examination in animals?

• Bleeding: Bleeding can occur during collection.
• Nerve damage: There is a risk of nerve injury, which can lead to movement difficulties, paralysis or a curved posture.
• Serious complications: In rare cases, the animal may have difficulty breathing and will then need to be artificially ventilated.

The CSF examination is technically demanding and requires specialist expertise. Serious complications are rare; careful performance keeps the risk low and ensures the reliability of the results.