contralateral superior homonymous quadrantanopsia due to inferior optic

Contralateral superior homonymous quadrantanopsia due

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contralateral superior homonymous quadrantanopsia due to inferior optic radiations (Meyer's loop) involvement.However, patients usually have intact expressive speech, motor, and primary sensory functions.Nondominant frontal lobe lesionstypically affect the way a person conveys emotion through speech (motor aprosodia), contralateral weakness, and apraxia.However, these lesions do not cause expressive aphasiaNondominant temporal lobe lesionscan impair ability to comprehend emotional gestures (sensory aprosodia).These patients can also develop a contralateral homonymous quadrantanopsia due to the inferior optic radiations involvement.Spinal muscular atrophy(Werdnig-Hoffmann disease) is characterized by generalized symmetric proximal muscle weakness and hyporeflexia.In contrast to botulism, spinal muscular atrophy does not affect the pupils, and the weakness is greater in the lower than the upper extremities. Clostridium botulinum: California, Pennsylvania, and Utah- botulism spores.Ingestion of inhaled botulism spores from environmental dust (eg, construction sites) leads to colonic colonization of C botulinum.This is followed by production and release of botulinum toxin, which blocks acetylcholine release at presynaptic neuromuscular junctions.Ingestion of raw honey also is a risk factor and the only preventable means of acquiring the infection.The diagnosis should be suspected in infants with bilateralbulbar palsies (eg, ptosis, sluggish pupillary response to light, poor suck and gag reflexes) followed by symmetric descending flaccid paralysis (hypotonia).Constipation and drooling due to autonomic dysfunction also occur.Treatment involves respiratory support, nasogastric tube feeding, and intravenous human-derived botulism immune globulin.Botulism immune globulin should be administered as soon as possible, even before diagnostic confirmation of stool spores or toxin.
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Oculomotor nerve palsy ischaracterized by mydriasis, ptosis, and "down and out" deviation of the ipsilateral eye.This may occur with nerve compression (eg, posterior communicating artery aneurysm) or microvascular nerve ischemia (eg, diabetes mellitus).Nerve compression is more likely to cause mydriasis as parasympathetic fibers are situated on the periphery of the oculomotor nerve.A lesion of the optic chiasmwould result in bitemporal hemianopsia.This may occur with anterior communicating artery aneurysms or tumors within the sella turcica (eg, craniopharyngioma, pituitary adenoma).Trochlear nerve palsyis typically traumatic or idiopathic and presents with vertical diplopia that worsenswhen the affected eye looks down and toward the nose (eg, walking downstairs, reading).Patients may compensate by tucking the chin and tilting the head away from the affected eye.
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  • Winter '14
  • Internal carotid artery, ischemic stroke, Anterior cerebral artery, Middle cerebral artery, Circle of Willis

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