First Aid Neurology Flashcards
ACA blood supply to functional areas and ACA strokes
leg - motor, sensory
language dominant hemisphere: broca’s area
prefrontal cortex: Functions in volition, motivation, and planning and organizing of complex behaviour.
ACA stroke deficits: (Right) leg motor cortex and sensory loss.
PFC/dom motor areas: grasp reflex, frontal lobe behavioral abnormalities, transcortical aphasia
MCA blood supply to functional areas:
L/R superficial divisions
Lenticulostriate
Left superficial branch: Broca’s area, Wernicke’s area, right motor/sensory head, neck, trunk, arm
Right superficial branch: left motor/sensory head, neck, trunk, arm
Lenticulostriate branches:
- striatum (caudate/putamen) - receive cortical inputs via BG –> D/indirect motor initiation and control
- Globus pallidus - output BG to thal and substantia nigra
- Internal capsule
MCA stroke types: superficial and lenticulostriate
superficial: (MCA infarct opp loss) motor/sensory head, neck, trunk, arm (L MCA-maybe nonfluent aphasia (broca), fluent aphasia (Wernicke’s)
lenticulostriate: (R/L) pure upper-motor hemiparesis due to damage to the basal ganglia (globus pallidus and striatum) and the genu of the internal capsule on the (R/L) side. Larger infarcts extending to the cortex may produce cortical deficits such as aphasia
PCA blood supply to functional areas: superficial and deep branches
PCA superficial branch:
- occipital lobe –Primary and secondary visual areas. Functions in the sensation and interpretation of visual inputs
- splenium corpus collosum (R/L visual areas share)
PCA deep branch:
- Thalamus –Relay center for descending and ascending information. Functions in the integration between cerebral cortex and the rest of the central nervous system.
- Internal capsule –Contains descending fibers of the lateral and ventral corticospinal tracts.
PCA strokes: left and right
Left PCA infarct: Right homonymous hemianopsia due to damage to left visual cortex in the occipital lobe. Extension to the splenium of the corpus collusom (alexia without agraphia). Larger infarcts w/internal capsule and thalamus hemisensory loss + right hemiparesis (disruption of the ascending and descending information)
Right: Left homonymous hemianopsia (damage to right visual cortex in the occipital lobe). Larger infarcts-internal capsule + thalamus (left hemisensory loss + left hemiparesis due to disruption of the ascending and descending information)
NT synthesis locations: Ach DA GABA NE SER
Ach - Basal nucleus of Meynert DA - ventral tegmentum, SNpc GABA - Nucleus accumbens NE - Locus ceruleus SER - Raphe nucleus
Aphasia:
locations -brocas/Wernicke’s
conduction aphasia
“trans aphasia” trend
Broca - inf frontal gyrus of frontal lobe
Wernicke - superior temporal gyrus of temporal lobe
Conduction aphasia - fluent speech, intact comprehension, impaired repetition
“trans aphasia” trend = repetition is intact
Infarcts : nondom parietal vs dom parietal
Nondominant parietal: hemispatial neglect (agnosia of contralateral side of world)
Dominant parietal: agraphia, acalculia, finger agnosia, L/R disorientation
Anterior Spinal Artery infarct / Medial Medullary Syndrome (paramedian branches ASA +/or VA’s)
lateral CS tract = contralateral paralysis U/LE
medial lemniscus = dec contralateral proprioception
caudal medulla = ipsilateral hypoglossal N dysfunction
PICA infarct / Lateral Medullary Syndrome (Wallenberg)
nystagmus, dec pain/temp sense ipsilateral face + contralateral body, *dysphagia (nucleus ambiguous), *hoarsenss
AICA infarct / Lateral pontine syndrome
Paralysis of face
Basilar Artery infarct
Involves medulla, pons, lower midbrain
-lock in syndrome
PCA infarct
- areas: occipital lobe, visual cortex
- Sx: contralateral hemianopia with macular sparing
Intracranial hemorrhage (brief): Epidural hematoma Subdural hematoma SAH Intraparenchymal hemorrhage
Epidural hematoma (MMA-maxillary A branch, lens, doesn't cross suture) Subdural hematoma (bridging veins, crescent, crosses suture) SAH (use nimodipine to prevent 4-10 day vasospasm after hemorrhage) Intraparenchymal hemorrhage (systemic HTN, amyloid angiopathy, reperfusion injury ---in BG and internal capsule)
Poliomyelitis - SC lesions
Anterior horn cells (ALS = ant horn cells + corticospinal tracts)
**asymmetric weakness
Fredreich ataxia
AR, repeat (GAA) ->fraxtin ->mitochondria
Sx: muscle weakness, loss DTRs, vibratory sense, proprioception = staggering gait, falls
Other Sx: DM, HCM (death), childhood kyphoscoliosis
Landmark dermatomes: C6, T4, T10, L1, L4, S2/3/4
C6 = thumbs up looks like 6 T4 = "teat pore" T10 = bellybut"ten" L1 = "IL" (inguinal ligament L4 = "Down on all 4's" = kneecaps S2/3/4 = "keep penis off the floor" (erection, sensation penile and anal zones)
Visual field defects - quadrantic anopia: temporal + parietal lobes
upper quadrantic anopia = temporal lobe infarct/lesion
lower quadrantic anopia = parietal lobe infarct/lesion
Herniation syndrome: 1 - Cingulate 2 - Transtentorial 3 - Uncal 4 - Cerebellar tonsillar
1 - Cingulate - under falx cerebri (compress ACA)
2 - Transtentorial (Downward) - displace brainstem, rupture paramedian basilar artery branches -> death
3 - Uncal (medial temporal lobe) herniation - compress ipsilarteral CN III (blown pupil, down and out gaze), ipsilateral PCA
4 - Cerebellar tonsillar herniation into foramen magnum = coma and death, compress brainstem
