Selected Diseases

Question 1

2 types of demyelination

Answer 1

Myelin is primary target or Neuron is primary target

Question 2

Myelin as primary target leads to

Answer 2

segmental demyelination first, axon stays intact, nerve conduction disrupted, eventually axon degenerates

Question 3

Neuron is primary target leads to

Answer 3

Axon degenerates first, Myelin degenerates secondarily. Wallerian degeneration occurs in the PNS

Question 4

segmental demyelination is?

Answer 4

myelin damaged over several segments (node to node) while axon is intact but conduction is disrupted, until eventually axon degenerates due to severe inflammation or repeated inflammation

Question 5

Guillain-Barre syndrome is?

Answer 5

major PNS demyelinating disease. Infection, immune reaction causes inflammation of myelin, segmental demyelination occurs at LMN fibers, decreased conduction since axon is still intact.

Question 6

another name for Guillian-Barre syndrome?

Answer 6

Acute idiopathic Polyneuritis or Postinfectious polyneuritis

Question 7

Symptoms of Acute idiopathic polyneuritis?

Answer 7

rapid progrssive symmetrical LMN paralysis (flaccid paralysis, areflexia) starting in the feet and ascending to include the upper body and face. Followed by PAIN.

Question 8

Multiple sclerosis is?

Answer 8

major NS demyelinating disease. Inflammation of the myelin sheath results in segmental demyelination in CNS white matter. Formation of assymetrical pathces/plaques develop in different areas of white matter.

Question 9

in MS, what fibers are commonly affected?

Answer 9

Heavily myelinated fibers like those of the corticospinal tracts, dorsal columns, medial longitudinal fasciculus, and optic nerve are commonly affected.

Question 10

Herpes Zoster (shingles) is?

Answer 10

Viral infection causing inflammation of Dorsal root or Cranial ganglia (trigeminal).

Question 11

Symptoms of shingles include?

Answer 11

Pain
Itching
Burning sensations (and a vesicular eruption)

Symptoms felt over one or dermatomes.

Question 12

Poliomyelitis is?

Answer 12

Inflammatory viral infection primarily destroys LMNSs in spinal cord AND brainstem

Question 13

What are the LMN symptoms of Poliomyelitis?

Answer 13

muscle weakness, flaccid paralysis, atrophy, loss of reflexes, etc.

Question 14

What is Spinal Muscular Atrophy (SMA)

Answer 14

Group of genetic disorders resulting in progressive degeneration of LMNs. Includes progressive infantile muscular atrophy (Werdnig- Hoffman disease, SMA1).

Question 15

What is Werdnig-Hoffman Disease?

Answer 15

Genetic progressive infantile LMN degeneration causing muscular atrophy (SMA)

Question 16

Amyotrophic lateral sclerosis (ALS) is?

Answer 16

Major Degenerative disease of motor system resulting from progressive death of LMNs and UMNs of SPINAL CORD and BRAINSTEM.

Question 17

Another name for Amyotrophic lateral sclerosis?

Answer 17

Lou Gehrig disease

Question 18

Lou Gehrig disease symptoms?

Answer 18

(ALS) Patients present with a mixture of:

• Bilateral flaccid paralysis (LMN symptoms)
• Spastic paralysis (UMN symptoms)

Question 19

What causes progessive death of lateral corticospinal tract where patients demonstrate Flaccid paralysis and Spastic paralysis?

Answer 19

Lou Gehrig Disease / ALS (Amyotrophic lateral sclerosis)

Question 20

Syringomyelia is?

Answer 20

Fluid filled cavity develops in the center of cord mainly at cervical segments. Edema at center compresses the Anterior White Commissure leading to compression of the decussating Spinothalamic fibers.

Question 21

What are symptoms of Syringomyelia?

Answer 21

Bilateral loss of pain and temperature commonly in the upper limbs since syringomyelia is fluid in the cervical segments compressing cervical spinothalamic fibers

Question 22

Tabes dorsalis is?

Answer 22

In late stage neurosyphillis, fiber degeneration of Dorsal white columns and dorsal root ganglions in Lumbosacral region. Main damage at Fasciculus Gracilis which is in charge of lower body discriminative sense (T6-/T7)

Question 23

Symptoms of Tabes Dorsalis?

Answer 23

Bilateral Loss of Discriminative Senses (vibration, conscious proprioeption, 2 point tactile discrimination).

Question 24

Subacute combined degeneration

Answer 24

Bilateral demyelination in:

1. Dorsal White columns
2. Lateral corticospinal tracts
3. Spinocerebellar tracts

Question 25

Caused by Vitamin B12 deficiency and pernicious anemia?

Answer 25

Subacute combined degeneration

Question 26

Similar spinal cord pathology and symptoms to Subacute combined degeneration. Also includes progressive degeneration of the cerebellum is?

Answer 26

Freidrich’s hereditary ataxia (autosomal recessive disease)

Question 27

1. Dorsal white columns (What is lost?) 2. Lateral corticospinal tracts (What is lost?) 3. Spinocerebellar tracts (What is lost?)

Answer 27

1. Dorsal white columns (bilateral loss discriminative senses) 2. Lateral corticospinal tracts (bilateral UMN symptoms) 3. Spinocerebellar tracts (uncoordinated movements, ataxia)

Question 28

Vitamin B12 neuropathy is also called?

Answer 28

Subacute combined degeneration occuring due to bilateral demyelination of Dorsal white columns, Lateral corticospinal, and Spinocerebellar tracts.

Question 29

Occlusion of the anterior spinal artery Results in?

Answer 29

Results in infarction of the ventral two-thirds of the spinal cord sparing the dorsal columns and horns.

Question 30

1. Gray matter of the ventral horn damage Results in what?

Answer 30

LMN symptoms (flaccid paralysis, loss of deep tendon reflexes, at the infarcted regions

Question 31

2. Lateral corticospinal tract in the lateral white column is damaged, Results in what?

Answer 31

UMN signs symptoms below the lesion (spastic paralysis, hyperreflexia, paraplegia or quadriplegia depending on level).

Question 32

3. Lateral spinothalamic tract in the lateral white columns is damaged, Results in what?

Answer 32

Bilateral loss of Pain & temperature one or two levels below the lesion.