Isa
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Human Anatomy
Anatomy Mnemonics For The BRACHIAL PLEXUS
~0.1 mins read
BRACHIAL PLEXUS Roots, Trunks, Divisions, Cords, Branches.
The brachial plexus branches into:
Remember with either Mnemonic
Randy Travis Drinks Cold Beers.
Robert Taylor Drinks Cold Beer.
or
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Human Anatomy
Anatomy Mnemonics For The Cranial Nerves
~0.5 mins read
The 12 CRANIAL NERVES:
I - Optic nerve
II - Olfactory nerve
III - Oculomotor nerve
IV - Trochlear nerve
V - Trigeminal nerve
VI - Abducens nerve
VII - Facial nerve
VIII - Acoustic (vestibulocochlear) nerve
IX - Glossophrayngeal nerve
X - Vagus nerve
XI - Spinal accessory nerve
XII - Hypoglossal nerve
Remember the 12 nerves in the following order
On Old Olympus Towering Tops, A Finn And German Viewed Some Hops
If you confuse which comes first (Optic or Olfactory) remember:
• You have I nose. You have II eyes. (I - Olfactory; II -- Optic)
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Picture source: USMLE first aid. Please buy a copy to get more info on this Mnemonic
Anatomy Mnemonics For Innervation Of Extraocularmotor Muscles (Ophthalmology))
~0.6 mins read
The nerves that supply the extraocularmotor muscles are
1. Abducens nerve or Cranial nerve VI (6)
2. Trochlear nerve or Cranial nerve IV (4)
3. Oculomotor nerve or Cranial nerve III (3)
• LR6 (SO4) R3
Explanation of Mnemonics
• LR6 = Lateral Rectus muscle --> Innervated by CN6 (VI) Abducens
• SO4 = Superior Oblique muscle --> Innervated by CN4 (IV) Trochlear
• R3 = The Rest of the 4 eyeball movers --> Innervated by CN3 (III)
The muscles innervated by CN 3 (III) Oculomotor nerve are
1. Superior Rectus
2. Inferior Rectus
3. Medial Rectus
4. Inferior Oblique
The Oblique muscles take the eyeballs in the opposite direction. For example the Left Oblique is tested with the patient looking Right and .
Mnemonic
Obliques go Opposite (Left SO and IO tested with patient looking right).
I O U: IO tested looking Up.
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Anatomy Mnemonics To Know Which Nerves Are Sensory, Motor Or Both Sensory And Motor
~0.6 mins read
The 12 Cranial nerves and their Types
I - Optic (Some)
II - Olfactory (Say)
III - Oculomotor (Marry)
IV - Trochlear (Money)
V - Trigeminal (But)
VI - Abducens (My)
VII - Facial (Brother)
VIII - Acoustic or Vestibulocochlear (Says)
IX - Glossophrayngeal (Big)
X - Vagus (Bras)
XI - Spinal accessory (Matter)
XII - Hypoglossal (More)
Mnemonic
Some Say Marry Money, But My Brother Says Big Bras Matter More (what cranial nerve is Motor, Sensory, or Both)Note: Take note of the letters in Bold
1. S = Denotes a Sensory nerve
A sensory nerve doesnt control any movement, however it aids in functioning of some of the sense organs
2. M = Denotes a Motor nerve
A motor nerve controls movement of a muscle, but doesnt supply nerve endings to any sense organ.
3. B = Denotes when a nerve has Both Sensory and Motor properties.
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Picture source: USMLE first aid. Please buy a copy to get more info on this Mnemonic
Neurology Mnemonics For Where The Myelin Is Produced In The CNS And PNS
~0.4 mins read
What is Myelin?
The Myelin Wraps and insulates axons in the nervous system.What is Axon?
An axon are tiny connections in the nervous system from where electrical signals move to other neurons. Thats how your brains tell you someone is touching you, or you are feeling pains for example.
Where the Myelin is produced
In Central Nervous System, CNS (including CN II), myelin is synthesized by oligodendrocytes.
In Peripheral Nervous System, PNS (including CN III-XII), myelin is synthesized by Schwann cells.
Mnemonic:
COPS (CO PS)
CNS = Oligodendrocytes,
PNS = Schwann cells.
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Neurology: What Are Schwann Cells
~0.5 mins read
Schwann cells are structures that surround the Axons (See my last post for a short explanation of what Axons are) in the Peripheral Nervous System.
This is the structure that surrounds and provides Myelin to wrap and insulate axons
Schwann cells are derived from the Neural Crest cells
Functions of the Schwann cell
1. Promote regeneration of the axon after injury.
2. One Schwann cell myelinates (surrounds and provides myelin) for one Peripheral Nevous System (PNS) Axon.
Which disease condition can result from injury to the Schwann cells
1. Guillain-Barré syndrome.
See my next post to know what Guillain Barre syndrome is all about
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Image source: Healthline.com
What Is Guillain-Barré Syndrome, GBS And How Do You Know If You Have It?
~3.0 mins read
What is Guillain-Barré syndrome?
It is an autoimmune condition that destroys Schwann cells via inflammation and demyelination of motor nerve fibers, sensory nerve fibers, and peripheral nerves (including CN III-XII). Guillain-Barré syndrome causes weakness or paralysis of various muscles in the body.
Some definitions to note
Inflammation means the body is trying to heal itself, but in this case, it ends up causing some damages
Demyelination means Myelin already produced by the Schwann cells in this case to protect the axons that are being destroyed.
What are the Symptoms and Signs of Guillain-Barré syndrome?
1. The most common symptom is muscle weakness or paralysis of various muscles in the body.
Which muscles of the body are commonly affected by Guillain-Barre syndrome?
It usually affects the muscles of the legs first then it can go upward to affect other muscles above which include:
1. Muscles of the Face
Usually affects the left and right sides of the face.
* For example, the person affected can't make facial expressions they used to make in the past.
* They are not able to smile
* They are not able to completely close their lips
2. Muscles used to breathe (Respiratory muscles)
When these muscles are affected, it can be fatal if the patient isn't put on artificial respiratory support.
3. Heart muscles
The affected person or their doctor may discover that they have some new heart issues that weren't there before.
* For example if the person is young, they might notice that they have high blood pressure (or low blood pressure)
4. Other muscles
The person might not be able to feel pressure or pain in some of their body parts as well.
How can you diagnose Guillain-Barré syndrome?
1. You can quickly spot GBS by taking note of muscle weakness that started in the legs and started climbing up to other muscles described above.
2. You can also check for depressed/absent Deep Tendon Reflexes
3. There might be Albuminocytologic dissociation at the hospital lab.
What is Albuminocytologic dissociation?
The medical personnel attending to you might pass a needle through your spine to remove and test your Cerebrospinal fluid (CSF) for an increase in protein despite having a normal cell count.
What are the common infections that can cause Guillain-Barré syndrome?
Guillain-Barré syndrome is commonly seen in the following infections
1. Infections with Campylobacter jejuni (Please see my next post to know more about Campylobacter jejuni bacteria?)
2. Infections with some viruses [eg, Zika]
What do these infections cause Guillain-Barré syndrome?
Guillain-Barré syndrome is believed to be caused by some organism or a part of it pretending to be an Axon.
When the body sends immune cells to fight these organisms pretending to be a part of your body, it ends up fighting your axons because it finds it difficult to distinguish between these deceptive organisms and itself.
What can cause a Flare or Trigger this syndrome?
It can be triggered by infections or even vaccinations or
It can also be triggered by Stress.
Would you die if you develop this syndrome?
No, you are more likely to survive if you get this condition because most people who had it in the past survived.
How long would it take to recover from Guillain-Barré syndrome?
It can take anywhere from weeks to months to completely recover from this condition.
How can you treat Guillain-Barré syndrome?
1. You must offer Respiratory support to every patient confirmed or even suspected of suffering from this syndrome until they recover.
2. Patients might be treated with Disease-modifying treatment such as Plasmapheresis or Intravenous (IV) immunoglobulins or antibodies.
What is Plasmapheresis?
This is the removal or exchange of blood plasma from the body. This is done to remove the immune cells attacking the body from the blood.
What are IV immunoglobulins?
IV immunoglobulins are given through the veins to counter the harmful effects of the body's own immunoglobulins.
Are Steroids usually given in Guillain-Barré syndrome?
No, Steroids have not been proven to help in the recovery of patients with this syndrome.
What is the most common type of Guillain-Barré syndrome called?
The most common type of GBS is called Acute Inflammatory Demyelinating Polyradiculopathy,
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What Is Campylobacter Jejuni (CJ) Bacteria And How Can It Infect You?
~1.2 mins read
Campylobacter jejuni is a Comma or S-shaped bacteria that commonly causes bloody diarrhea, especially in children.
How can this Bacteria Infect you?
The Campylobacter jejuni bacteria can infect you in the following ways:
1. When you eat Chicken or Meat that is not properly cooked.
2. When you consume raw milk that has been contaminated.
3. Having direct or indirect contact with someone who is already infected.
This can happen if the infected person forgets to wash their hands properly after using the toilet.
4. Domesticated animals can also be a source of infection.
For example, Dogs, Cats, Pigs etc
What are the complications of getting infected with Campylobacter jejuni?
Infection with this bacteria can lead to
1. Guillain-Barré syndrome
2. Reactive Arthritis
How can infection with this bacteria be diagnosed?
Your lab technician would look for the following characteristics before confirming an infection with CJ
1. Gram-negative bacteria
2. Coma or S-shaped bacteria
3. Bacteria has polar flagella
- A pollar flagellum is present at one end of the bacteria, but can rotate, clockwise or anti-clockwise depending
4. Bacteria is Oxidase positive
- Oxidase positive organisms can break down oxygen
5. Bacteria grows at a high temperature (42 degree centigrade)
Should I be bothered if I get infected with Campylobacter jejuni?
No, many times when this bacteria infects people, it goes away on its own, you just have to drink plenty fluids preferably Oral Rehydration Solution.
Precaution
Please report to the nearest clinic if the number of stools per day are getting beyond 5 or if the symptoms are causing you significant distress
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