The document discusses cerebrospinal fluid (CSF) analysis and various neurological disorders and diagnostic tests. It provides details on CSF formation and circulation in the brain and spinal cord. Various CSF disorders like hydrocephalus and their symptoms are explained. Electrodiagnostic tests including electromyography, nerve conduction velocity, and evoked potentials used to evaluate nerve and muscle disorders are described. The roles of antibodies and autoimmune disorders affecting the nervous system like autoimmune encephalitis are outlined. Diagnostic tests for neurological conditions such as MRI, its advantages and limitations are summarized.

1. Cerebrospinal Fluid Analysis
Presented by : Gajraj Singh Bika

2. Introduction
 CSF is clear,colorless and transparent.
 Circulates through cavity of the : brain,subarachnoid cord and central canal of spinal
cord
 Part of etracellular fluid(ECF)
Properties :
 Volume : Approximately 150 mL
 Rate of formation : Approximately 0.3 mL/min
 Specific gravity : 1.005
 Reaction : Alkaline

3. Composition

4. Formation of CSF
Site of formation
 Formed by the choroid plexus situated within the
 ventricles.
 The choroid plexus are tuft of capillary projections present
 inside ventricles and covered by:
• Pia mater
• Ependymal covering.
Mechanism of formation
 Formed by process of secretion.
 Does not involve ultrafiltration or dialysis.
 Uses energy.
 Active transport mechanism is involved in secretion.

5. Collection of CSF
 Collected by :
 Cisternal puncture
 Lumber puncture
 In Cisternal puncture
- CSF is collected by passing needle between occipital bone and atlas, so enters
the cisterna magna.
 In Lumber puncture
- The lumber puncture needle is introduced into the subarachnoid space in the
Lumber region between the third and fourth lumber spines.
 Uses of Lumber puncture
- Collecting CSF for diagnostic purpose.
- Injecting drugs for spinal anesthesia analgesia and chemotherapy.
- Measuring pressure exerted by CSF.

7. CSF Disorders
 Hydrocephalus
- Abnormal accumulation of CSF in the skull with enlargement of head.
 2 types of Hydrocephalus:
1. Non- Communicating(Internal Hydrocephalus) : Due to the obstruction of any of
the foramen through which CSF escapes results in dilation of ventricular cavity.
2. Communicating( External Hydrocephalus) : Due to blockage of Arachnoid Villi.

8. Symptoms:
 Headache
 Vomiting
 Atrophy of brain
 Mental weakness
 Convulsions
 Normal pressure Hydrocephalus
– Same as Communicating Hydrocephalus but it is
 due to decreased CSF absorption.
Symptoms :
 Gait instabiltiy
 Urinary incontinence
 Dementia

9. Electrodiagnosis
 Is a filed of study that, by employing the science of electrophysiology, uses
electrical technology to study human neurophysiology.
 Information needed to answer any questions regarding the nerve injury, muscle
injury, muscle disease, localization, and prognosis can be thus obtained through
the help of electrodiagnostic testings.
 The information collected through the testing helps to focus treatment on the
exact site of injury.
 This is accomplished via a variety of electrodiagnostic tests like:
- Electromyography(EMG)
- Nerve conduction velocity(NCV)
- Evoked potentials(EP)

10. Electromyography
 An EMG, used in conjunction with a neurological examination, helps establish a diagnosis
and the extent of a problem by measuring the electrical activity of a muscle in response to
stimulation.
- An EMG may be used to evaluate a variety of problems, including the following:
 Nerve damage from compression by a disk in the neck or the back
 Nerve compression from carpal tunnel syndrome
 Neuromuscular diseases such as amyotrophic lateral sclerosis (ALS), poliomyelitis,
myasthenia gravis and muscular dystrophy
 Peripheral neuropathy caused by such conditions as diabetes, pernicious anemia and heavy
metal toxicity
Procedure:
 The electrical activity detected by this electrode is displayed on an oscilloscope.
 You may be asked to contract the muscle.
 To perform intramuscular EMG, a needle electrode is inserted through the skin into the
muscle tissue. A trained medical professional observes the electrical activity while inserting
the electrode.

11. Nerve conduction velocity
 A nerve conduction velocity (NCV) test is used to assess nerve damage and dysfunction.
Also known as a nerve conduction study, the procedure measures how quickly electrical
signals move through your peripheral nerves.
An NCV test can be used to diagnose a number of muscular and neuromuscular disorders,
including:
 Guillain-Barre syndrome
 carpal tunnel syndrome
 Charcot-Marie-Tooth (CMT) disease
 herniated disk disease
 chronic inflammatory polyneuropathy and neuropathy
 sciatic nerve problems
 peripheral nerve injury

12. Procedure:
Two electrodes are placed on the skin over the nerve. One electrode stimulates the
nerve with a very mild electrical impulse and the other electrode records it. The
resulting electrical activity is recorded by another electrode. This is repeated for each
nerve being tested.

13. Evoked Potential test
 Evoked potential tests measure the time it takes for the brain to respond to
sensory stimuli as a way of detecting and monitoring problems or irregularities
with how the nervous system is functioning.
 The visual evoked response (VER) is the most commonly used evoked potential
test in the diagnosis of multiple sclerosis (MS). Conducting gel and electrodes are
applied to the scalp. The location will depend on the type of response being
recorded
 Sensory evoked potentials studies measure electrical activity in the brain in
response to stimulation of sight, sound, or touch. When the brain is stimulated by
sight, sound, or touch, signals travel along the nerves to the brain. There,
electrodes detect the signals and display them for your doctor to interpret.

14. Antibodies
 What is antibody?
 Antibody, also called immunoglobulin, a protective protein produced by the
immune system in response to the presence of a foreign substance, called an
antigen. Antibodies recognize and latch onto antigens in order to remove them
from the body.
 Antibodies are Y-shaped proteins that are produced by the immune system to
help stop intruders from harming the body. When an intruder enters the body,
the immune system springs into action. These invaders, which are called
antigens, can be viruses, bacteria, or other chemicals.
 There are five immunoglobulin classes (isotypes) of antibody molecules found in
serum: IgG, IgM, IgA, IgE and IgD. They are distinguished by the type of heavy
chain they contain.

15. Autoimmune Disorders:
 An autoimmune disease is a condition in which your immune system mistakenly
attacks your body. The immune system normally guards against germs like
bacteria and viruses. When it senses these foreign invaders, it sends out an army
of fighter cells to attack them.
 The exact cause of autoimmune disorders is unknown. One theory is that some
microorganisms (such as bacteria or viruses) or drugs may trigger changes that
confuse the immune system. This may happen more often in people who have
genes that make them more prone to autoimmune disorders.
 Common Autoimmune Disorders :
 Rheumatoid arthritis, Systemic lupus erythematosus, Inflammatory bowel disease,
Multiple sclerosis, Type 1 diabetes mellitus, Guillain-Barre syndrome, Chronic
inflammatory demyelinating polyneuropathy, Psoriasis and Autoimmune
Encephalitis.

16. Autoimmune encephalitis (AE)
 Autoimmune encephalitis (AE) is a type of brain inflammation where the body's
immune system attacks healthy cells and tissues in the brain or spinal cord.
 Autoimmune encephalitis may be associated with antibodies to proteins on the
surface of nerve cells, or within nerve cells. Some of these proteins are involved in
passing signals between nerve cells. In some cases it occurs in association with
cancer. Research regarding why specific antibodies attack the body's healthy cells
is ongoing. Autoimmune encephalitis generally occurs sporadically, in people with
no family history of the condition.

18. Symptoms
 cognitive impairment
 memory difficulties
 seizures
 involuntary movements
 slowed or loss of ability to speak
 behavioral changes such as agitation
 loss of inhibition
 hallucinations (visual or auditory)
 paranoid thoughts
 severe anxiety
 sleep disruption including severe insomnia
 decreased level of consciousness – to the point of unresponsiveness, catatonia or
coma
 weakness or numbness of part of the body
 loss of balance
 vision changes

19. Diagnosis :
 testing typically used to aid in the diagnosis of AE includes MRI of the brain with
contrast, electroencephalogram (EEG), blood and cerebrospinal fluid analysis for
markers of inflammation. Your doctors may specifically look for antibodies which
the immune system to attack the brain causing encephalitis. These antibodies may be
found both in the blood and cerebrospinal fluid, so testing both is necessary in most
cases.
Treatment :
First line treatment :
 removal of a teratoma (if present) that could be triggering the autoimmune response;
 use of anti-inflammatory drugs (ie. steroids);
 use of plasmapheresis to remove harmful antibodies from blood; and
 treatment with intravenous immunoglobulin (IVIG); to increase removal of antibodies,
inhibit binding of the harmful antibodies, and decrease the inflammatory response to
antibodies.
The three most common “second line” drugs used for AE are:
 Rituximab
 CellCept
 Cytoxan (cyclophosphamide).

20. MRI
 Magnetic resonance imaging (MRI) is a medical imaging technique used in
radiology to form pictures of the anatomy and the physiological processes of the
body. MRI scanners use strong magnetic fields, magnetic field gradients, and
radio waves to generate images of the organs in the body.
 MRI can detect a variety of conditions of the brain such as cysts, tumors,
bleeding, swelling, developmental and structural abnormalities, infections,
inflammatory conditions, or problems with the blood vessels. It can determine if a
shunt is working and detect damage to the brain caused by an injury or a stroke.
 MRI is sensitive to changes in cartilage and bone structure resulting from injury,
disease, or aging. It can detect herniated discs, pinched nerves, spinal tumors,
spinal cord compression, and fractures.

22. Difference between MRI and FMRI

23. Advantages of MRI
 No ionizing radiation.
 Variable thickness in any plane.
 Better contrast resolution.
 Many details without IV contrast.

24. Disadvantage of MRI
 Very expensive.
 Dangerous for patient with metallic device placed within the body.
 Difficult to be performed on claustrophobic patient.
 Movement during imaging can cause blur.
 RF transmitter can cause severe burns if mishandled.

25. Principle:
 MRI makes use of magnetic properties of certain atomic nuclei.
 Hydrogen nucleus present in water molecule and therefore in all body tissues.
 The hydrogen nuclei partially aligned by a strong magnetic field in the scanner.
Components of MRI:
 Scanner
 Computers
 Recording Hardware

26. Who can’t have an MRI scan
 A cardiac pacemaker
 Certain clips in your head from brain operation
 A cochlear implant
 A metallic foreign body in your eye
 Had surgery in the last 8 weeks
 If you are pregnant
Who can be diagnosed by an MRI scan
 Most ailments of the brain, including tumours.
 Most spinal injuries/Conditions
 ENT conditions
 Hydrocephalus