Sensory system

Question 1

What types of sensation is transmitted by the dorsal columns?

Answer 1

Fine, discriminative touch, proprioception, vibration

Question 2

What fibers are there in the dorsal columns?

Answer 2

large myelinated fibers

Question 3

Where do the dorsal columns deccusate?

Answer 3

Medulla:
nucleus gracilis ( lower limbs)
nucleus nucleus cuneatus (upper limbs)

Question 4

What is the course and destination of the dorsal columns?

Answer 4

medulla(deccusates) - medial lemiscus - thalamus - sensory cortex

Question 5

What types of sensation is transmitted by the spinothalamic tracts?

Answer 5

poorly localized touch, pain, temperature

Question 6

What fibers are there in the spinothalamic tracts?

Answer 6

small non-myelinated fibers (first affected by local anestheisa)

Question 7

Where do the spinothalamic tracts deccusate?

Answer 7

at the level of cord entry

Question 8

What is the course and destination of the spinothalamic tracts?

Answer 8

Lateral (fast pain, temp) cord
Anterior (touch, slow pain) cord

• via the brainstemreticular formation
• thalamus
• sensory cortex

Question 9

What are the five nuclei in the thalamus?

Answer 9

Sensory
Motor
Limbic 
Association
Nonspecific

Question 10

What are common causes of single nerve lesions?(5)

Answer 10

Diabetes, RA, hypothyroidism, trauma, vascular

Question 11

What are common causes of glove and stocking polyneuropathy? (9)

Answer 11

diabetes
uremia
malnutrition
paraproteinemias
cancer
colagenosis
toxings
inflammation
inherited neuropathies (i.e Charcot-Marie-Tooth)

Question 12

What typically causes nerve root lesions?(2)

Answer 12

disc compression or tumor

Question 13

What are causes of complete cord lesion?(4)

Answer 13

trauma, tumor, MS, inflammation

Question 14

What are causes of hemisection of the spinal cord?(3)

Answer 14

inflammation, MS, intraspinal tumor

Question 15

What is “central cord syndrome”?

And what are the typical causes(2)

Answer 15

Loss of temp. and pain sensation AT the level of the lesion (typically cervical)
large lesion may affect whole body under lesion

• syringomyelia, intramedullary tumors

Question 16

Isolated lesion of the dorsal columns are typically a result of which two diseases?

Answer 16

Vit B12 deficiency
Tabes dorsalis (syphilis)

Question 17

What is anterior spinal syndrome?

Answer 17

• Loss of pain and temp. sensation below the lesion

- caused by occlusion of ant. spinal artery(Adamkiewicz a.)

Question 18

A lesion in the sensory pathways of the brainstem will produce what sensory symptoms?

Answer 18

ipsilateral loss on the face

contralateral loss on trunk and limbs

Question 19

A lesion in the sensory pathways of the thalamus will produce what sensory symptoms?

Answer 19

loss on all sensation on the contralateral side

Question 20

A lesion in the sensory pathways of the internal capsule will produce what sensory symptoms?

Answer 20

loss on all sensation on the contralateral side

Question 21

A lesion in sensory cortex will produce what sensory symptoms?

Answer 21

no superficial sensory disturbances
unable to localize stimuli
loss of sterognosia(object shape) and discrimination

Question 22

What is the clinical presentation of Oculomotor lesion?

Answer 22

Lateral and downward eye
diplopia
Dilated and fixed pupil
Ptosis

Question 23

What nuclei is involved in the light reflex and the accomodation reflex

Answer 23

Edinger westfal nucleus

Question 24

What is the clinical manifestation of Horner syndrome?

Answer 24

Unilateral:
Miosis
ptosis
anhidrosis
endopthalmos
vasodilation

Question 25

How does trochlear nerve palsy present clinically?

Answer 25

Head tilt and chin tuck to contralateral side

Question 26

What is internuclear ophtalmoplegia

Answer 26

lesion to LMF | problems with adduction on ipsilateral side and vertical nystagmus on other side

Question 27

bilateral internuclear opthalmoplegia is typical for which disease?

Answer 27

MS

Question 28

A lesion in the trigeminal nerve will result i what clinical findings?(3)

Answer 28

Pain/loss of sensation loss of corneal reflex (V1) Paralysis of ipsilateral chewing muscles

Question 29

What can be the clinical findings of facial nerve lesions? (5)

Answer 29

Paralysis of ipsilateral facial muscles (peripheral lesion) Paralysis of lower contralateral face (central lesion) Hyperacusis Dry eyes Dry mouth loss of taste (ant 2/3) if proximal to chorda tympani

Question 30

What are the clinical signs of Vestibular nerve lesion?(4)

Answer 30

vertigo with falling to affected side inabillity to maintain vertical posture nystagmus and blurred vision nausea and vomiting

Question 31

What are the clinical signs of Cochlear nerve lesion?(2)

Answer 31

Diminished hearing/deafness | Tinnitus

Question 32

What are the clinical signs of Glossopharyngeal lesion?(4)

Answer 32

Palatal palsy Dysphagia Loss of reflexes from carotid body and sinus loss of taste/touch on post. third of tongue

Question 33

What are the clinical signs of Vagus nerve lesion?(4)

Answer 33

Dysphagia palatal palsy(uvula deviates to opposite side) Hoarseness loss of vagal cardio/gastro/resp reflexes

Question 34

What are clinical signs of Spinal Accessory nerve lesion? (3)

Answer 34

weakness of head rotation weakness of shoulder shrugging vocal cord paralysis and hoarseness (carry vagal fibers)

Question 35

What are clinical signs of Hypoglossal nerve lesion?(3)

Answer 35

Paralysis and atrophy ipsilaterally Dysarthria Dysphagia

Question 36

Where is the nucles of CN3 located?

Answer 36

midbrain

Question 37

Where are the nuclei of CN 4,5,6,78 located?

Answer 37

Pons (CN5 also in medulla)

Question 38

Where are the nuclei of CN 10,12 located?

Answer 38

medulla

Question 39

Where are the nuclei of CN 11?

Answer 39

spinal cord

Question 40

What are the signs of bulbar palsy?(5)

Answer 40

``` Dysarthria Dysphagia diminished mandibular reflex paresis of pharynx and palate loss of gag reflex paralysed tongue ```

Question 41

where is the lesion in bulbar palsy?

Answer 41

CN 5,9,10,12

Question 42

What are the signs of pseudobulbar palsy?(7)

Answer 42

``` Dysarthria Dysphagia increased mandibular reflex increased pharyngeal reflex paralysis of tongue(no atrophy or fasiculations) Affect incontinence Fronal release ( primitive reflexes) ```

Question 43

Where is the lesion in pseudobulbar palsy?

Answer 43

Bilateral lesion of corticonuclear fibers