Neurosurgery Flashcards
history
-is there neurologic disease causing systemic issues or systemic issues causing neurological disease
-can the pt withstand anesthesia
-where is the lesion, what caused it, how do we treat it
cerebral lesions
-cause contralateral deficits in extremities
-mostly require a bilateral lesion for it to be apparent tho
-olfactory CN1- doesnt cross so unilateral lesion results in ipsilateral anosmia
-optic CN2, oculomotor CN3, trochlear CN4, abducens CN6- both eyes cant MOVE to contralateral side of lesion (look towards lesion), both eyes cant SEE contralaterally, pupillary light reflex is consensual bc its mediated by the brainstem
-trigeminal CN5- contralateral loss of facial sensation
-facial CN7- contralateral lower half of face paralysis // if facial nerve itself is damaged (bells palsy) -> total ipsilateral hemifacial paralysis
-vestibulocochlear CN8- needs to be bilateral for hearing loss, can cause vertigo
-glossopharyngeal CN9, vagus CN10, accessory (CN11)- needs to be bilateral usually
-hypoglossal CN12- contralateral weakness of the tongue, more pronounced with direct lesions
right optic nerve damage and light shined into right eye
-no response
-if light shined in left eye -> both pupils constrict
-right oculomotor nerve damage and light shined in right eye -> only left pupil constricts
-right oculomotor nerve damaged and light shined in left eye -> only left pupil constricts
CNS vs PNS lesions
-PNS
-follow dermatomes or glove and stocking
-sensory loss with pain
-CNS
-defects in extremity
-loss of sensation with no pain
-exception- thalamic pain syndrome- causes diffuse pain
thalamic syndrome
-usually caused by occlusion of thalamogeniculate branches of PCA supplying posterior thalamus
-contralateral hemianesthesia, ataxia, excruciating neurogenic pain
-unresponsive to analgesics
-symptoms vary
-CNS exception
upper motor neuron vs lower motor neuron defect
-UPPER
-spastic weakness
-no significant muscle atrophy
-no fasciculations and fibrillations
-hyperreflexia
-babinski reflex may be present
-LOWER
-flaccid weakness
-significant atrophy
-fasciculations and fibrillations
-hyporeflexia
-no babinski reflex
spinal cord defect
-UMN signs with spinal dermatome defect
-loss of pain-temperature in one leg and loss of proprioception in the other leg
brain stem lesion
-cranial nerve deficit with contralateral extremity hemiparesis (right facial paralysis and left hemiplegia)
-you can rule out cerebral cortex lesions bc it would be confine to contralateral deficit (left facial paralysis and left hemiplegia)
-CN2- loss of vision in one eye
-CN3,4, or 6- pupillary inequality or difficulty moving one eye
-CN5- unilateral weakness of masseter muscle
-CN7- total unilateral facial paralysis
-CN8- unilateral hearing loss
-CN9/and or 10- difficulty swallowing
-CN10- hoarseness
-CN11- difficulty raising shoulder or turning head
cerebellar or basal ganglia lesions
-awkward movement
-not weak
-intended movement awkwardness- tremor, ataxia -> cerebellar
-involuntary awkwardness- resting tremor, chorea, athetosis, hemiballismus -> basal ganglia lesions
parts of brain and function
-brocas- expressing language
-wernickes- understanding language
-temporal- memory, recognizing faces, emotions, language
-parietal- perception, spatial awareness, manipulating objects, spelling
corpus callosum
-connects brain left and right
-coordinate
brown sequard syndrome
-hemisection of the spinal cord
-ipsilateral loss of all sensory modalities at level of the lesion
-ipsilateral flaccid paralysis at level of lesion
-ipsilateral spastic paraparesis below the lesion
-ipsilateral loss of vibration and position sense below the lesion
-contralateral loss of pain and temperature below the lesion
posterior column- medial lemniscus pathway of CNS
-proprioception, vibration, discriminative touch, weight discrimination and stereognosis
-signals travel up spinal cord in posterior column
-fibers cross over in medulla -> become the medial lemniscus pathway ending in thalamus
-thalamic fibers reach cortex
MCA stroke
-middle cerebral artery
-contralateral hemiparesis (usually upper)
-contralateral hypesthesia
-ipsilateral hemianopsia (vision loss)
-gaze goes towards the side of lesion
-agnosia- cant recognize
-receptive or expressive aphasia
-weakness in arms and face
-aphasia
-ex. left MCA stroke -> right face/arm > leg numbess and weakness, APHASIA, left gaze preference
-ex. right MCA stroke -> left face/arm > leg numbness and weakness, LEFT HEMISPATIAL NEGLECT, right gaze preference, agraphesthesia/asteroagnosia
PCA stroke
-posterior cerebral artery
-cortical blindness
-visual agnosia
-altered mental status
-impaired memory
-hemiparesis
-hemianopsia
-ataxia
-dizziness
VBA stroke
-veterbrobasilar artery
-vertigo
-nystagmus
-diplopia
-ipsilateral cranial nerve deficit with contralateral motor deficits
-dysphagia
-syncope
-ataxia
ACA stroke
-anterior cerebral artery
-frontal lobe function affected
-disinhibition
-primitive reflexes- grasping, sucking
-AMS
-impaired judgement
-gait apraxia
-urinary incontinence
-hemiparesis, especially inferior limbs!
-EX. left ACA stroke -> right leg numbness/weakness, transcortical motor aphasia, ideomotor apraxia
-ex. right ACA stroke -> left leg numbness/weakness, motor neglect, possible ideomotor apraxia
internal carotid artery stroke
-ACA + MCA
-ipsilateral monocular visual loss (amurosis) secondary to central retinal arterial occlusion (CRAO)
-hemiparesis
-aphasia
-hemianopsia
basilar artery stroke
-before PCA
-breathing difficulties
-sensory or balance disorders
-ataxia
-nystagmus
-opisthotonus- possessed looking
-tremors and vomiting
cerebellar artery
-sensory difficulties
-headaches
-fever
-vomiting
-cerebellar signs
wallenberg (lateral medullary syndrome)
-vertebral artery or PICA occlusion
-stroke of the brain stem
-lateral medulla ischemia
-ipsilateral palate weakness
-impaired coordination
-contralateral sensory disturbances of trunk and extremities -> impaired gait and falls.
-Horner syndrome- decreased pupil size, drooping eyelid, decreased sweating on one side
-dizziness, double vision, pain or loss of pain on one side of the face, loss of taste on one side of the tongue, difficulty swallowing, slurred speech, and hoarseness