Random Stephens Stuff

Question 1

What does a posterior column lesion on the right side result in, in general?

Answer 1

Right sided Loss (ipsilateral) of proprioception discriminative touch and vibratory touch below the lesion

page 195

Question 2

What artery is associated with lateral medulla lesions?

Answer 2

Posterior inferior cerebellar artery PICA syndrome

pg 196

Question 3

Unilateral lesion of FG results in what?

Answer 3

Ipsilateral loss of proprioception, vibratory sensation, and 2 point tactile discrimination in the lower half of the body and extremeties

• Associated with posteior spinal artery

Question 4

Unilateral lesion of FC results in what?

Answer 4

Unilateral loss of proprioception 2 pt discrimination and vibratory sense on the same side as the lesion on the upper half of the body.

• assocaited with posterior spinal artery

Question 5

What are symptoms of Lateral Corticospinal Tract lesions in the spinal cord?

Answer 5

• Ipsilateral spastic paralysis
• Hyperreflexia
• Hypertonia
• Babinski sign
• Clonus
• Disuse atrophy

(These are upper motor neuron damage signs)

Both anterior and posterior spinal arteries according to diagram in Somatosensory tract 2 lecture

Question 6

Lateral Spinothalmic Tract (LSTT) unilateral lesion symptoms?

Answer 6

• contralateral loss of pain and temprerature sensation two sensory dermatome segments below the level of the lesion
• Long circumfrential branches of basilar artery and branches of the AICA associated with this

Question 7

What happens if the Lateral Reticulosopinal Tract is transceted?

Answer 7

• Transection above S2 interrupts LRST to sacral autonomic nucleus and the patient loses their ability to voluntarily void their bladder, so urinary retention occurs.

Question 8

What happens if AWC is damaged?

Answer 8

• Bilateral loss of pain and temp to upper extremeties

Question 9

Syringomyelia?

Answer 9

• Central cord syndrome caused by syrinx or intramedullary mass or infarct. Occlusion of Great anterior artery aka Artery of adamkiewicz
• also damages AWC

Question 10

What results with damage to the Anterior horn?

Answer 10

• LMN paralysis from destruction of the lower motor neurons or their axons.
• It is seen with flaccid paralysis areflexia atonia atrophy and fasciculations
• Anterior spinal artery supplies this area

Question 11

What does the spinal lemniscus do?

Answer 11

• Conveys pain and temp from the opposite half of the body. It is lateral or posterolateral to the medial lemniscus

Question 12

What does the Medial Lemniscus do?

Answer 12

• Conveys proprioceptive vibratory and 2 point tactile discrimation from the opposite half of the body.
• At the upper pons and mmidbrain the ML has fibers that convey taste from ipsilateral tongue and pharynx

Question 13

What does the trigeminal lemniscus do?

Answer 13

• Conveys pain temp and crude sensations from opposite half of the face

Question 14

What does the descending tract of trigeminal do?

Answer 14

• Conveys ipsilateral paon and temp form the face. Located in posterolateral area of medulla.
• Descending tract of V and underlying descending nucleus of V are adjacent to the spinal lemniscus

Question 15

Lateral Lemniscus?

Answer 15

LL conveys bilateral auditory info but mostly info from the opposite side. Located in lateral brainstem

Question 16

MLF (Medial longitudinal Fasciculus) functions

Answer 16

• Conveys vestibular info from maculae utricle and sccule and crista ampullaris to CN III IV and VI.
• Critical role in aligning gaze with the heads position and its located next to the midline and anteiro to central grey
• In the medulla and lower pons it is located at dorsal medial lemniscus

Question 17

MLF lesion results in?

Answer 17

• Results in internuclear opthalmoplegia. Abnormal respponse to horiozontal gaze in direction opposite of the lesion.
• Unioateral lesions of the MLF result in imparitment or loss of of adduction of ipsilateral eye and nystagmus of the abducting eye

Question 18

Corticospinal Tract (CST) function location

Answer 18

• Conoveys descending motor info from motor cortex
• In the midbrain it makes up middle of the crus cerebri
• In pons its split into fascicle by pontine nuclei and pontocerebellar fibers
• Medulla it forms pyramids

Question 19

CST unilateral lesion?

Answer 19

Contralateral spastic hemiplegia

Fibers decusate in the medulla in the pyramids

Question 20

Corticobulbar tract function and location?

Answer 20

• Brainstem cranial nerve motor nuclei innervated by corticobulbar fibers!
• They decusate in the lower pons btw trigeminal and abducens

Question 21

Unilateral lesions of CBT?

Answer 21

• Denervation of brainstem motor nuclei below lesion

Question 22

Unilateral Lesions of CBT above decussation level? Below?

Answer 22

• Contralateral paralysis of lower half of face Supranuclear Facial Palsy
• Lesions below decussation result in ipsilateral cranial nerve palsies