Monday, 4-25-Brainstem Lesions (Stephens)

Question 1

A lesion of the hypoglossal nucleus results in:

Answer 1

Protruded tongue deviates toward the side of the affected nucleus

Question 2

The level of a brainstem lesion may be determined by identifying the coordinates of the __ affected CN and/or nuclei.

Answer 2

Highest (most superior)

Question 3

A lesion of __ leads to contralateral loss of pain and temp on opposite 1/2 of the body

Answer 3

SL

Question 4

A lesion of __ leads to loss of proprioception, 2-pt tactile discrimination, and vibratory sensation on the opposite 1/2 of the body

Answer 4

ML

Question 5

A lesion of __ leads to loss of pain and temp sensation on opposite side of face

Answer 5

TL

Question 6

A lesion of __ leads to contralateral spastic hemiplegia

Answer 6

Corticospinal tracts

Question 7

What structures yield only ipsilateral deficits?

Answer 7

Cranial nerves
Desc tract of V
Posterior columns in lower medulla

Question 8

A lesion of __ leads to loss pain/temp sensations from the same side of the face

Answer 8

Desc tract of V

Question 9

Which structures lead to predominantly contralateral deficits?

Answer 9

LL

Brachium of inferior colliculus

Question 10

A lesion of the LL and/or brachium of inferior colliculus leads to:

Answer 10

Bilateral dimunition of hearing which is most predominant in the contralateral ear

Question 11

A lesion in these cranial nerves leads to ipsilateral CN deficits and contralateral loss of pain and temp sensations from the body:

Answer 11

V, VII, IX, X, and XI

These CNs exit the brainstem in close association with the SL. As a result, a lesion in any one of these regions may involve 1 of these nerves as well as the SL

Question 12

Which 4 CNs exit the brainstem adjacent to the CST and lead to alternating hemiplegia with lesions?

Answer 12

Alternating HYPOGLOSSAL hemiplegia
Alternating ABDUCENS hemiplegia
Alternating TRIGEMINAL hemiplegia
Alternating OCULOMOTOR hemiplegia

XII, VI, V, III

Question 13

You are doing a neurological exam on a patient and find that the tongue protrudes to the right and there is +4/4 muscle reflexes on the left, hypertonicity on the left, and well as paralysis on the left side of the body. What is the diagnosis?

Answer 13

Alternating hypoglossal hemiplegia

Destruction of XII on the right results in ipsilateral paralysis of muscles of tongue and atrophy of ipsilateral muscles of the tongue

Destruction of CST at this level results in contralateral spastic hemiplegia

Question 14

A pt presents with a protrusion of the tongue to the left, hyperreflexia/hypertonicity/paralysis of the right UE and LE as well as hyperreflexia/hypertonicity/paresis of the left LE (not UE). What is the diagnosis?

Answer 14

Alternating hypoglossal hemiplegia and destruction of contralateral CST (A12H + CST)

Destruction of CN XII=ipsilateral paralysis and atrophy of tongue muscles

Destruction of ipsilateral CST=contralalteral spastic hemiplegia

Partial destruction of contralateral CST=some degree of ipsilateral spastic paralysis

Question 15

A pt presents with protrusion of the tongue to the right as well as a loss of proprioception, 2-pt tactile discrimination, and vibratory sensations on the left side of the body. What is the diagnosis?

Answer 15

Alternating hypoglossal hemiplegia and destruction of ipsilateral ML (A12H + ML)

Destruction of ipsilateral XII and CST

Destruction of ipsilateral ML=contralateral loss of proprioception, 2-pt tactile discrimination, and vibratory sensations from the body

Question 16

A pt presents with internal strabismus of the right eye as well as hyperreflexia/hypertonia/paralysis of both the left UE and LE. What is the diagnosis?

Answer 16

Alternating abducent hemiplegia (A6H)

Destruction of VI=ipsilateral paralysis of lateral gaze and/or internal strabismus

Destruction of CST at this level results in contralateral spastic hemiplegia

Question 17

A patient presents to you with an internal strabimus of the right eye as well as a facial palsy of the right side. He also displays hyperreflexia/hypertonia/paralysis of the left side of the body. What is the diagnosis?

Answer 17

Millard-Gubler’s syndrome (A6H + 7)

Includes signs of alternating abducens hemiplegia plus a VII lesion

Destruction of VII=ipsilateral facial palsy, loss of taste from ant 2/3 of tongue, decreased lacrimation, and hyperacusis

Question 18

__ includes the signs of an alternating abducens hemiplegia plus additional signs due to the dorsal extension of the lesion

Answer 18

Syndrome of Foville

1) destruction of ML=contralateral loss of prop/2pt/tactile discrimination, and vibratory sensations from body
2) destruction of MLF=internuclear ophthalmoplegia
3) VII palsy
4) Destruction of CROSSED corticobulbar fibers=denervation of ipsilateral NUCLEUS AMBIGUUS and HYPOGLOSSAL nucleus

Question 19

In syndrome of Foville, destruction of the crossed corticobulbar fibers results in denervation of the:

Answer 19

Ipsilateral: Nucleus ambiguus and hypoglossal nucleus

Question 20

A pt presents with a loss of sensation from the right half of the face and scalp as well as paralysis of the muscles of mastication on the right side. He also displays hyperreflexia/hypertonia/paralysis of the left UE and LE. What is the diagnosis?

Answer 20

Alternating trigeminal hemiplegia (A5H)

Destruction of V=ipsilateral loss of all sensations from half of the face and scalp, and paralysis of ipsilateral muscles of mastication

Destruction of CST=contralateral spastic hemiplegia

Question 21

A pt presents with a loss of sensation from the left side of the face and scalp as well as paralysis of the left facial muscles of mastication. In addition, there is loss of proprioception/2pt tactile discrimination from the body and limbs on the right side, as well as a supranuclear facial palsy on the right side of the face and protrusion of the tongue to the right. What is the diagnosis?

Answer 21

Alternating V hemiplegia with a dorsal expansion (A5H + ML)

Signs of A5H plus deficits associated with involvement of more dorsally located structures

Destruction of ML=contralateral loss of proprioception and 2-pt tactile discrimination from body and limbs

Destruction of UNCROSSED corticobulbar fibers=denervation of the contralateral CN nuclei: abducens nucleus, 1/2 of facial nucleus (supranuclear facial palsy), hypoglossal and nucleus ambiguus

Question 22

A pt presents with external strabisumus, pupillary dilation and complete ptosis of the right eye. He also has spastic hemiplegia of the left side of the body. You notice that he has a resting tremor of his left hand when attempting to sign his name. What is the diagnosis?

Answer 22

Webers syndrome (Alternating Oculomotor Hemiplegia) or A3H

Destruction of III=ext strabismus, pupillary dilation, complete ptosis

Destruction of CST=contralateral spastic hemiplegia

Destruction of substantia nigra=contralalteral resting tremor

Destruction of UNCROSSED corticobulbar tract=contralateral brainstem motor nuclear palsies, including supranuclear facial palsy

Question 23

A pt presents with dysphagia and paresis of the right palatal muscles as well as a loss of pain and temperature sensation on the left side of the body. What is the diagnosis?

Answer 23

Lesion of the nucleus ambiguus and the SL

• destruction of nucleus ambiguus=dysphagia,dysarthria,hoarseness, and paresis of ipsilateral palatal muscles
• destruction of SL=contralateral loss of pain and temp sensations from the body
• lesions may extend medially to include the ML and solitary nucleus

Question 24

A pt presents with loss of pain/temp sensation of the right side of the face as well as a loss of pain and temp sensation of the left side of the body. The pt also does not have a gag reflex, has dysphonia, and swallowing is difficult. What is the diagnosis?

Answer 24

Lateral medullary syndrome (Wallenberg’s syndrome or Syndrome of the PICA)

• Destroyed SL=contralateral hemianalgesia
• Destroyed desc tract of V=ipsilateral loss of pain and temp from face
• Alternating hemianalgesia
• Destroyed glossopharyngeal and vagus nerves
• Destroyed nucleus ambiguus
• Destroyed solitary nucleus
• Destroyed spinocerebellar tracts
• Irritation of vestibular nuclei=nystagmus

Question 25

You are reviewing imaging of an acoustic neuroma that has enlarged in the posterior cranial fossa. As the tumor enlarges, what are the structures you worry about that would lead to Cerebellopontine angle (CPA) syndrome?

Answer 25

Lateral aspect of: Pons, cerebellum, and medulla

Question 26

What are signs/symptoms indicative of Cerebellopontine (CPA) syndrome?

Answer 26

Deafness and Alternating hemianalgesia

Destruction of VIII –> deafness and vestibular disturbances

Question 27

How would you distinguish Wallenburg syndrome from Cerebllopontine angle syndrome?

Answer 27

Wallenburg –> Dysphagia

Cerebellopontine angle –> deafness

Both will have alternating hemianalagesia

Question 28

Benedikt’s syndrome is a lesion of the ___

Answer 28

Midbrain tegmentum

Question 29

A pt presents with CN III palsy, loss of proprioception and 2 pt tactile discrimination of the left upper and lower limbs. There are also lesions of the red nucleus, fibers of the superior cerebellar peduncle, and midbrain tegmentum. What is the diagnosis?

Answer 29

Benedikt’s syndrome (lesion of midbrain tegmentum)

Question 30

__ is due to a lesion of the superior colliculus. The principal sign of this syndrome is paralysis of upward gaze.

Answer 30

Parinaud’s syndrome

Question 31

Parinaud’s syndrome may due to ___

Answer 31

Pineal tumor or varix of great vein of Galen

Question 32

In Parinaud’s syndrome, lesions may also destroy __ which leads to a concomitant loss of consensual light reflex

Answer 32

Posterior commissure

Question 33

Thalamic syndrome (Dejerine-Roussy syndrome) is usually due to thrombosis of the posterior choroidal or thalamogeniculate branches of the ___

Answer 33

Posterior cerebral arteries

Question 34

“Crawling ants” sensations are a hallmark of ___

Answer 34

Thalamic syndrome

Question 35

A lesion of the nucleus ambiguus results in:

Answer 35

Deviation of the uvula away from the affected nucleus