Week 110 Peripheral neuropathy Flashcards
Name nerves affected by compression neuropathies
Affect single nerve Radial nerve Median nerve Ulnar nerve Meralgia paresthetica Common peroneal nerve Sciatic nerve
Describe radial nerve entrapment
Saturday night palsy
Commonly falling asleep on outstretched arm
Wrist drop
Describe median nerve entrapment
Carpal tunnel syndrome Thenar wasting Loss of wrist flexion Loss of sensation over medial fingers Hypothenar wasting
Meralgia Paresthetica
Compression of the lateral cutaneous nerve of the thigh
Lateral cutaneous nerve - purely sensory function
Loss of sensation over lateral thigh to knee
Tight Trousers Syndrome
Common peroneal nerve
Peroneal = fibular
Foot drop
Guillain-Barre syndrome
Rapid onset muscle weakness Autoimmune response after infection 30% - campylobacter (link to Week 101) Ascending polyneuropathy Starts in hands and feet - moves to lungs Can lead to respiratory arrest Important to do spirometry to check lung function Treatment - intravenous immunoglobulins
Myasthenia gravis
Autoimmune
Antibodies against acetylcholine receptor
Prevents acetylcholine binding to receptor - action potential - muscle contraction
FATIGUABILITY - giveaway in SBA
Drooping of eyelids - LPS weakness
Weakness of muscles of swallowing - dysphagia (difficulty swallowing)
Voice - quiet (muscles which control vocal cords weaken)
Treatment - Pyridostigmine (inhibits acetylcholinesterase - enzyme which breaks down acetylcholine)
Lambert Eaton Syndrome
Similar to Myasthenia Gravis
Get gait disturbance before eye signs
Reflexes get better with increased testing
Due to antibodies against voltage gated calcium channels
No calcium influx no release of acetylcholine from vesicles
No depolarisation
Charcot Marie Tooth
Hereditary motor and sensory neuropathy Foot drop Hammer toes - always curled Inverted champagne bottle sign PMP 22 - marker
Diabetic (toxic neuropathy)
Associated with poorly controlled diabetes
Excess glucose damages nerve cells
Glove and stocking distribution
Name excitatory NTs in the brain
Glutamic acid
Ach
Aspartic acid
NA (mostly)
Name inhibitory NTs in the brain
GABA
Dopamine
Serotonin
Glycine
Prosencephalon
forebrain (cerebral hemispheres, pituitary, hypothalamus)
Rhombencephalon
(hindbrain) medulla, pons, cerebellum
Mesencephalon
midbrain (everything else)
