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Flashcards in Brainstem Lesions Deck (22):
1

lesion of dorsal motor nucleus of X

transient parasympathetic deficits

2

lesion of descending motor nucleus of V

ipsilateral loss of pain and temp sensations from 1/2 of face

3

lesion of posterior columns

ipsilateral loss of prop, 2 pt tactile, and vibratory sensations

4

lesion of lateral lemniscus

bilateral diminution of hearing which is most predominant in contralateral ear

5

cranial Ns 5, 7, 9, 10, 11 and spinal lemniscus

these cranial Ns exit the brainstem close to the spinal lemniscus
-as a result, a lesion in one of these may involve the N and the spinal lemniscus so causes ipsilateral CN deficits and contralateral loss of pain and temp from body

6

alternating hemiplegias

involve 3, 5, 6, 12 b/c of their close association with the corticospinal tract
-yields ipsilateral CN deficits and contralateral motor paralysis or paresis

7

alternating hypoglossal hemiplegia

1. destruction of hypoglossal N--ipsilateral paralysis of Ms of tongue and atrophy of ipsilateral Ms of tongue
2. destruction of CST--contralateral spastic hemiplegia

8

alternating hypoglossal hemiplegia and destruction of contralateral CST

1. destruction of hypoglossal N--ipsilateral paralysis and atrophy of tongue Ms
2. destruction of ipsilateral CST--contralateral spastic hemiplegia
3. partial destruction of contralateral CST--some degree of ipsilateral spastic paralysis

9

alternating hypoglossal hemiplegia and destruction of ipsilateral medial lemniscus

1. destruction of hypoglossal N--ipsilateral paralysis and atrophy of tongue Ms
2. destruction of ipsilateral CST--contralateral spastic hemiplegia
3. destruction of ipsilateral ML--contralateral loss of proprioception, 2 pt tactile, and vibratory sensations from body

10

alternating abducens hemiplegia

1. destruction of abducens N--ipsilateral paralysis of lateral gaze/internal strabismus
2. destruction of CST--contralateral spastic hemiplegia

11

Millard Gubler's Syndrome

A6H+7
1. destruction of abducens N--ipsilateral paralysis of lateral gaze/internal strabismus
2. destruction of CST--contralateral spastic hemiplegia
3. destruction of facial N--ipsilateral facial palsy, loss of taste sensations from anterior 2/3 of tongue, decreased lacrimation, and hyperacusis

12

Syndrome of Foville

A6H+ML
1. destruction of abducens N--ipsilateral paralysis of lateral gaze/internal strabismus
2. destruction of CST--contralateral spastic hemiplegia

3. destruction of ML--contralateral loss of proprioception, 2 pt tactile discrimination, vibrations
4. destruction of medial longitudinal fasciculus (MLF)--internuclear ophthalmoplegia
5. facial N may be involved
6. destruction of CROSSED corticobulbar fibers results in denervation of ipsilateral nucleus ambiguus and hypoglossal N--dysarthria, dysphagia, protrusion of tongue
-this is not due though to a problem with CN 9, 10, or 12 but instead due to the crossed CBF and the highest CN involved (CN 6)

13

alternating trigeminal hemiplegia

1. destruction of trigeminal N--ipsilateral loss of all sensations from half of face and scalp and ipsilateral paralysis of Ms of mastication
2. destruction of CST--contralateral spastic hemiplegia

14

alternating trinomial hemiplegia with dorsal expansion

A5H+ML
1. destruction of trigeminal N--ipsilateral loss of all sensations from half of face and scalp and ipsilateral paralysis of Ms of mastication
2. destruction of CST--contralateral spastic hemiplegia

3. destruction of ML--contralateral loss of prop, 2 pt tactile, vibration from body and limbs
4. destruction of UNCROSSED corticobulbar fibers results in denervation of contralateral CN nuclei
-abducens nucleus
-1/2 of facial nucleus results in paralysis of mimetic Ms on lower half of face--supranuclear facial palsy
-hypoglossal nucleus
-nucleus ambiguus

15

Weber's Syndrome

-alternating oculomotor hemiplegia
1. destruction of oculomotor N--external strabismus, pupillary dilation, complete ptosis
2. destruction of CST--contralateral spastic hemiplegia
3. destruction of substantia nigra--contralateral resting tremor
4. destruction of UNCROSSED CBF--contralateral brainstem motor nuclear palsy including supra nuclear facial palsy

16

lesion of nucleus ambiguus and spinal lemniscus

1. destruction of nucleus ambiguus--dysphagia, dysarthria, hoarseness, paresis of ipsilateral palatal Ms
2. destruction of SL--contralateral loss of pain and temp sensations from body
3. lesion may extend medially to include the medial lemniscus and solitary nucleus
-ML: contralateral loss of prop/2 pt tactile hemianesthesia of body
-solitary nucleus: ipsilateral anesthesia of palate and pharynx, loss of taste sensations from 1/2 of tongue and pharynx

17

Lateral Medullary Syndrome
Wallenburg's Syndrome

1. destruction of spinal lemniscus--contralateral hemianalgesia
2. destruction of descending tract of V--ipsilateral loss of pain and temp from face
3. alternating hemianalgesia--ipsilateral loss of pain and temp sensations from face and contralateral loss of pain and temp from body
4. destruction of glossopharyngeal and vagus Ns--DYSPHAGIA
5. destruction of nucleus ambiguus
6. destruction of solitary nucleus--ipsilateral anesthesia of palate and pharynx, loss of taste sensations from 1/2 of tongue and pharynx
7. destruction of spinocerebellar tracts--asynergia or hypotonia
8. irritation of vestibular nuclei resulting in nystagmus

18

Cerebellopontine Angle Syndrome (CPA)

-common tumor of posterior cranial fossa in adults is acoustic neurinoma--as tumor enlarges it compresses the lateral aspect of pons, cerebellum, and medulla

1. destruction of vestibulocochlear N--DEAFNESS and vestibular disturbances
2. destruction of facial N--Bell's Palsy
3. alternating hemianalgesia--ipsilateral loss of pain and temp sensations from face and contralateral loss of pain and temp from body
-destruction of descending tract of V--ipsilateral loss of pain and temp from face
-destruction of spinal lemniscus--contralateral hemianalgesia of body
4. involvement of cerebellar peduncles results in some degree of ipsilateral cerebellar ataxia, intention tremor, dysmetria, and dysdiadochokinesia

19

Benedikt's Syndrome

-lesion of midbrain tegmentum
1. destruction of oculomotor N--external strabismus, pupillary dilation, complete ptosis
2. destruction of ML--contralateral loss of prop, 2 pt, and vibratory sensation from body and limbs
3. lesions of red nucleus, superior cerebellar peduncle, and midbrain tegmenjtum--ipsilateral oculomotor palsy, contralateral motor dysfunction--tremor, ataxia, or choreiform movements

20

Parinaud's Syndrome

-lesion of superior colliculus which contains a center for controlling upward gaze
-principal sign of this syndrome--paralysis of upward gaze
-may be due to pineal tumor or varix of Great V of Galen
-lesions may destroy posterior commissure and concomitant loss of consensual light reflex

21

unilateral lesion of VPM and VPL

-results in contralateral hemianesthesia
-loss of pain and temp on opposite side of face and body
-prop and tactile discrimination from contralateral body
-prop, tactile discrimination, and taste sensations from ipsilateral head

22

thalamic syndrome (Dejerine-Roussy Syndrome)

-usually due to thrombosis of PCA
-pts exhibit:
-state of constant spontaneous pain w/o appropriate external strabismus
-modification of emotional control--pt exhibits extreme mood swings from laughter to sobbing in a short time
-may involve contralateral hemihypalgeia (crawling ant sensations), hemiparesis, homonymous hemianopsia, auditory deficits