definitions neuro mm

The flashcards below were created by user Pongo on FreezingBlue Flashcards.

  1. Autonomic Neuropathies
    Autonomic neuropathies are peripheral nerve disorders with disproportionate involvement of autonomic fibers.
  2. Horner's Syndrome
    Horner's syndrome is ptosis, miosis, and anhidrosis due to dysfunction of cervical sympathetic output.
  3. Multiple Sytem Atrophy
    Multiple system atrophy is a relentlessly progressive neurodegenerative disorder causing pyramidal, cerebellar, and autonomic dysfunction. It includes 3 disorders previously thought to be distinct: olivopontocerebellar atrophy, striatonigral degeneration, and Shy-Drager syndrome. Symptoms include hypotension, urinary retention, constipation, ataxia, rigidity, and postural instability. Diagnosis is clinical. Treatment is symptomatic, with volume expansion, compression garments, and vasoconstrictor drugs.
  4. Pure Autonomic Failure
    Pure autonomic failure results from neuronal loss in autonomic ganglia, causing orthostatic hypotension and other autonomic symptoms.
  5. Chronic Pain
    Chronic pain is pain that persists or recurs for > 3 mo, persists > 1 mo after resolution of an acute tissue injury, or accompanies a nonhealing lesion. Causes include chronic disorders (eg, cancer, arthritis, diabetes) and injuries (eg, herniated disk, torn ligament), and many primary pain disorders (eg, neuropathic pain, fibromyalgia, chronic headache). Various drugs and psychologic treatments are used.
  6. Neuropathic Pain
    Neuropathic pain results from damage to or dysfunction of the peripheral or central nervous system, rather than stimulation of pain receptors. Diagnosis is suggested by pain out of proportion to tissue injury, dysesthesia (eg, burning, tingling), and signs of nerve injury detected during neurologic examination. Although neuropathic pain responds to opioids, treatment is often with adjuvant drugs (eg, antidepressants, anticonvulsants, baclofen, topical drugs).
  7. Agnosia
    Agnosia is inability to identify an object using one or more of the senses. Diagnosis is clinical, often including neuropsychologic testing, with brain imaging (eg, CT, MRI) to identify the cause. Prognosis depends on the nature and extent of damage and patient age. There is no specific treatment, but occupational therapy may help patients compensate.
  8. Amnesias
    Amnesia is partial or total inability to recall past experiences. It may result from traumatic brain injury, degeneration, metabolic disorders, seizure disorders, or psychologic disturbances. Diagnosis is clinical but often includes neuropsychologic testing and brain imaging (eg, CT, MRI). Treatment is directed at the cause.
    Transient global amnesia is disturbed memory typically caused by vascular or ischemic lesions in the brain. Diagnosis is primarily clinical but includes laboratory tests and CT, MRI, or both to evaluate central circulation. The amnesia typically remits spontaneously but may recur. There is no specific treatment, but underlying abnormalities are corrected.
  10. Aphasia
    Aphasia is language dysfunction that may involve impaired comprehension or expression of words or nonverbal equivalents of words. It results from dysfunction of the language centers in the cerebral cortex and basal ganglia or of the white matter pathways that connect them. Diagnosis is clinical, often including neuropsychologic testing, with brain imaging (CT, MRI) to identify cause. Prognosis depends on the cause and extent of damage and on patient age. There is no specific treatment, but speech therapy may promote recovery.
  11. Apraxia
    Apraxia is inability to execute purposeful, previously learned motor tasks, despite physical ability and willingness, as a result of brain damage. Diagnosis is clinical, often including neuropsychologic testing, with brain imaging (eg, CT, MRI) to identify cause. Prognosis depends on the cause and extent of damage and patient age. There is no specific treatment, but physical and occupational therapy may modestly improve functioning and patient safety.
  12. Ischemic Stroke
    • Ischemic stroke is sudden neurologic deficits that result from focal cerebral ischemia associated with permanent brain infarction (eg, positive diffusion-weighted MRI). Common causes are (from most to least common) nonthrombotic occlusion of small, deep cortical arteries (lacunar infarction); cardiogenic embolism; arterial thrombosis that decreases cerebral blood flow; and artery-to-artery embolism. Diagnosis is clinical, but CT or
    • MRI is done to exclude hemorrhage and confirm the presence and extent of stroke. Thrombolytic therapy may be useful acutely in certain patients. Depending on the cause of stroke, carotid endarterectomy, antiplatelet drugs, or warfarin may help reduce risk of subsequent strokes.
  13. Intracerebral Hemorrhage
    Intracerebral hemorrhage is focal bleeding from a blood vessel in the brain parenchyma. The cause is usually hypertension. Typical symptoms include focal neurologic deficits, often with abrupt onset of headache, nausea, and impairment of consciousness. Diagnosis is by CT or MRI. Treatment includes BP control, supportive measures, and, for some patients, surgical evacuation.
  14. Subarachnoid Hemorrhage (SAH)
    Subarachnoid hemorrhage is sudden bleeding into the subarachnoid space. The most common cause of spontaneous bleeding is a ruptured aneurysm. Symptoms include sudden, severe headache, usually with loss or impairment of consciousness. Secondary vasospasm (causing focal brain ischemia), meningismus, and hydrocephalus (causing persistent headache and obtundation) are common. Diagnosis is by CT or MRI; if neuroimaging is normal, diagnosis is by CSF analysis. Treatment is with supportive measures and neurosurgery or endovascular measures, preferably in a referral center.
  15. Coma and Impaired Consciousness
    Coma is unresponsiveness from which the patient cannot be aroused. Similar, but less severe disturbances of consciousness may also occur. The mechanism involves dysfunction of both cerebral hemispheres or of the reticular activating system (also known as the ascending arousal system). Causes may be structural or nonstructural (eg, toxic or metabolic disturbances). Damage may be focal or diffuse. Diagnosis is clinical; identification of cause usually requires laboratory tests and neuroimaging. Treatment is immediate stabilization and specific management of the cause. For long-term coma, adjunctive treatment includes passive range-of-motion exercises, enteral feedings, and measures to prevent pressure ulcers.
  16. Vegetative State
    A vegetative state is absence of responsiveness and awareness due to overwhelming dysfunction of the cerebral hemispheres, with sufficient sparing of the diencephalon and brain stem to preserve autonomic and motor reflexes and sleep-wake cycles. Patients may have complex reflexes, including eye movements, yawning, and involuntary movements to noxious stimuli but show no awareness of self or environment. Diagnosis is clinical. Treatment is supportive. Prognosis with persistent deficits is bleak, and withdrawal of care should be discussed with family members.
  17. Locked-in Syndrome
    Locked-in syndrome is a state of wakefulness and awareness with quadriplegia and paralysis of the lower cranial nerves, resulting in inability to show facial expression, move, speak, or communicate, except by coded eye movements.
  18. Brain Death
    Brain death is loss of function of the entire cerebrum and brain stem, resulting in coma, no spontaneous respiration, and loss of all brain stem reflexes. Spinal reflexes, including deep tendon, plantar flexion, and withdrawal reflexes, may remain. Recovery does not occur.
  19. Delirium and Dementia
    Delirium (sometimes called acute confusional state) and dementia are the most common causes of cognitive impairment, although affective disorders (eg, depression) can also disrupt cognition. Delirium and dementia are separate disorders but are sometimes difficult to distinguish. In both, cognition is disordered; however, dementia affects mainly memory, and delirium affects mainly attention.
  20. Delirium
    Delirium is an acute, transient, usually reversible, fluctuating disturbance in attention, cognition, and consciousness level. Causes include almost any disorder, intoxication, or drug. Diagnosis is clinical, with laboratory and usually imaging tests to identify the cause. Treatment is correction of the cause and supportive measures.
  21. Dementia
    Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are used to identify treatable causes. Treatment is supportive. Cholinesterase inhibitors can sometimes temporarily improve cognitive function.
    Lewy body dementia is chronic cognitive deterioration characterized by cellular inclusions called Lewy bodies in the cytoplasm of cortical neurons.
    Alzheimer's disease causes progressive cognitive deterioration and is characterized by senile plaques, β-amyloid deposits, and neurofibrillary tangles in the cerebral cortex and subcortical gray matter.
    Vascular dementia is acute or chronic cognitive deterioration due to diffuse or focal cerebral infarction that is most often related to cerebrovascular disease.
    HIV-associated dementia is chronic cognitive deterioration due to brain infection by HIV.
    Frontotemporal dementia (FTD) refers to sporadic and hereditary disorders that affect the frontal and temporal lobes, including Pick's disease.
    Normal-pressure hydrocephalus is characterized by gait disturbance, urinary incontinence, dementia, enlarged brain ventricles, and normal or slightly elevated CSF pressure.
  28. Generalised Seizures
    • In generalized seizures, the aberrant electrical discharge diffusely involves the entire cortex of both hemispheres from the onset, and consciousness is usually lost. Generalized seizures result most often from metabolic disorders and sometimes from genetic disorders. Generalized seizures include the following:
    • Infantile spasms
    • Absence seizures
    • Tonic-clonic seizures
    • Atonic seizures
    • Myoclonic seizures
  29. Partial Seizures
    • In partial seizures, the excess neuronal discharge occurs in one cerebral cortex, and most often results from structural abnormalities. Partial seizures may be
    • Simple (no impairment of consciousness)
    • Complex (reduced but not complete loss of consciousness)
  30. Circadian Rhythm Sleep Disorders
    Circadian rhythm sleep disorders are caused by desynchronization between internal sleep-wake rhythms and the light-darkness cycle. Patients typically have insomnia, excessive daytime sleepiness, or both, which typically resolve as the body clock realigns itself. Diagnosis is clinical. Treatment depends on the cause.
  31. Narcolepsy
    Narcolepsy is characterized by chronic excessive daytime sleepiness, often with sudden loss of muscle tone (cataplexy). Other symptoms include sleep paralysis and hypnagogic and hypnopompic hallucinations. Diagnosis is by polysomnography and multiple sleep latency testing. Treatment is with modafinil, various stimulants, or Na oxybate for excessive daytime sleepiness and certain antidepressants for associated symptoms. I
    Idiopathic hypersomnia is excessive daytime sleeepiness with or without long sleep time; it is differentiated from narcolepsy by lack of cataplexy, hypnagogic hallucinations, and sleep paralysis.
  33. Parasomnias
    Parasomnias are undesirable behaviors that occur during entry into sleep, during sleep, or during arousal from sleep. Diagnosis is clinical. Treatment may include drugs and psychotherapy.
  34. Periodic Limb Movement Disorder and Restless Legs Syndrome
    Periodic limb movement disorder (PLMD) and restless legs syndrome (RLS) are characterized by abnormal motions of and sometimes sensations in the lower or upper extremities, which may interfere with sleep.
  35. Cluster Headache
    Cluster headaches cause excruciating, unilateral periorbital or temporal pain, with ipsilateral autonomic symptoms (ptosis, lacrimation, rhinorrhea, nasal congestion). Diagnosis is clinical. Acute treatment is with parenteral triptans, dihydroergotamine, or O2. Prevention is with verapamil, lithium, topiramate, divalproex, or a combination.
  36. Idiopathic Intracranial Hypertension
    Idiopathic intracranial hypertension causes increased intracranial pressure without a mass lesion or hydrocephalus, probably by obstructing venous drainage; CSF composition is normal.
  37. Migraine
    Migraine is an episodic primary headache disorder. Symptoms typically last 4 to 72 h and may be severe. Pain is often unilateral, throbbing, worse with exertion, and accompanied by symptoms such as nausea and sensitivity to light, sound, or odors. Auras occur in about 25% of patients, usually just before but sometimes after the headache. Diagnosis is clinical. Treatment is with triptans, dihydroergotamine, antiemetics, and analgesics. Preventive regimens include lifestyle modifications (eg, of sleeping habits or diet) and drugs (eg, β-blockers, amitriptyline, topiramate, divalproex).
  38. Post–Lumbar Puncture and Other Low–Pressure Headaches
    Low-pressure headaches result from reduction in CSF volume and pressure due to lumbar puncture or spontaneous or traumatic CSF leaks.
  39. Tension-Type Headache
    Tension-type headache causes mild generalized pain without the incapacity, nausea, or photophobia associated with migraine.
  40. Brain Abscess
    A brain abscess is an intracerebral collection of pus. Symptoms may include headache, lethargy, fever, and focal neurologic deficits. Diagnosis is by contrast-enhanced MRI or CT and sometimes culture. Treatment is with antibiotics and usually surgical drainage.
  41. Encephalitis
    Encephalitis is inflammation of the parenchyma of the brain, resulting from direct viral invasion. Acute disseminated encephalomyelitis is brain and spinal cord inflammation caused by a hypersensitivity reaction to a virus or another foreign protein. Both disorders can be caused by many viruses. Symptoms include fever, headache, and altered mental status, often accompanied by seizures or focal neurologic deficits. Diagnosis requires CSF analysis and neuroimaging. Treatment is supportive and, for certain causes, includes antiviral drugs.
  42. Progressive Multifocal Leukoencephalopathy (PML)
    Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of the JC virus. The disease usually occurs in patients with impaired cell-mediated immunity. It causes subacute and progressive CNS demyelination, multifocal neurologic deficits, and death, usually within a year. Diagnosis is with contrast-enhanced CT or MRI plus CSF PCR. In AIDS patients, highly active antiretroviral therapy may slow down the progression, and patients taking immunosuppressants may improve when those drugs are withdrawn. Treatment is otherwise supportive.
  43. Rabies
    Rabies is a viral encephalitis transmitted by the saliva of infected bats and certain other infected mammals. Symptoms include depression and fever, followed by agitation, excessive salivation, and hydrophobia. Diagnosis is by serologic tests or biopsy. Vaccination is indicated for people at high risk of exposure. Postexposure prophylaxis involves wound care and passive and active immunoprophylaxis. The disorder is almost universally fatal. Treatment is supportive.
  44. Subdural Empyema
    Subdural empyema is a collection of pus between the dura mater and arachnoid. Symptoms include fever, lethargy, focal neurologic deficits, and seizures. Diagnosis is by contrast-enhanced CT or MRI. Treatment is with surgical drainage and antibiotics.
  45. Prion Diseases
    • Prion diseases are progressive, fatal, and untreatable degenerative brain disorders. They include:
    • Creutzfeldt-Jakob disease (CJD), the prototypic example
    • Gerstmann-Sträussler-Scheinker disease (GSS)
    • Fatal insomnia (FI)
    • Variant CJD (vCJD)
    • Kuru
  46. Creutzfeldt-Jakob Disease (CJD)
    Creutzfeldt-Jakob disease is a sporadic or familial prion disease. Bovine spongiform encephalopathy (mad cow disease) is a variant form. Symptoms include dementia, myoclonus, and other CNS deficits; death occurs in 1 to 2 yr. Transmission can be prevented by taking precautions when handling infected tissues and using bleach to clean contaminated instruments. Treatment is supportive.
  47. Gerstmann-Sträussler-Scheinker Disease
    Gerstmann-Sträussler-Scheinker disease is an autosomal dominant prion brain disease that begins during middle age.
  48. Fatal Insomnia
    Fatal insomnia is a typically hereditary prion disorder causing difficulty sleeping, motor dysfunction, and death.
  49. Meningitis
    Meningitis is inflammation of the meninges of the brain or spinal cord.
  50. Acute Bacterial Meningitis
    Acute bacterial meningitis is a fulminant, often fatal pyogenic infection beginning in the meninges. Symptoms include headache, fever, and stiff neck. Without rapid treatment, obtundation and coma follow. Diagnosis is by CSF tests. Treatment requires antibiotics, often beginning empirically with a 3rd- or 4th-generation cephalosporin, vancomycin, and ampicillin; corticosteroids are usually given. Residual morbidity is common.
  51. Aseptic Meningitis
    Aseptic meningitis is inflammation of the meninges with CSF lymphocytic pleocytosis and no cause apparent after routine CSF stains and cultures. Viruses are the most common cause. Other causes may be infectious or noninfectious. Symptoms include fever, headache, and meningeal signs. Viral aseptic meningitis is usually self-limited. Treatment is usually symptomatic.
  52. Subacute and Chronic Meningitis
    Meningeal inflammation that lasts > 2 wk (subacute meningitis) or > 1 mo (chronic meningitis) may have infectious or noninfectious causes (eg, cancer). Diagnosis requires CSF analysis, usually after CT or MRI. Treatment is directed at the cause.
  53. Conjugate Gaze Palsies
    A conjugate gaze palsy is inability to move both eyes in a single horizontal (most commonly) or vertical direction.
  54. Internuclear Ophthalmoplegia
    Internuclear ophthalmoplegia is characterized by paresis of eye adduction in horizontal gaze but not in convergence. It can be unilateral or bilateral.
  55. Third Cranial Nerve Disorders
    Third cranial nerve disorders can impair ocular motility, pupillary function, or both. Symptoms and signs include diplopia, ptosis, and paresis of eye adduction and of upward and downward gaze. If the pupil is affected, it is dilated, and light reflexes are impaired. If the pupil is affected or patients are increasingly unresponsive, CT is done as soon as possible.
  56. Fourth Cranial Nerve Palsy
    Fourth cranial nerve palsy impairs the superior oblique muscle, causing paresis of vertical gaze, mainly in adduction.
  57. Sixth Cranial Nerve Palsy
    Sixth cranial nerve palsy affects the lateral rectus muscle, impairing eye abduction. The eye may be slightly adducted when the patient looks straight ahead. The palsy may be secondary to nerve infarction, Wernicke's encephalopathy, trauma, infection, or increased intracranial pressure, or it may be idiopathic. Determining the cause requires MRI and often lumbar puncture and evaluation for vasculitis.
  58. Trigeminal Neuralgia
    Trigeminal neuralgia is severe paroxysmal, lancinating facial pain due to a disorder of the 5th cranial nerve. Diagnosis is clinical. Treatment is usually with carbamazepine or gabapentin; sometimes surgery is required.
  59. Hemifacial Spasm
    Hemifacial spasm refers to unilateral painless, synchronous contractions of facial muscles due to dysfunction of the 7th cranial (facial) nerve and/or its motor nucleus. Hemifacial spasm results from nerve compression by a pulsating blood vessel, similar to that in trigeminal neuralgia.
  60. Bell's Palsy
    Bell's palsy is sudden, idiopathic, unilateral peripheral 7th cranial nerve palsy. Symptoms are hemifacial paresis of the upper and lower face. There are no specific tests for diagnosis. Treatment may include corticosteroids, antiviral drugs (eg, acyclovir), lubrication of the eye, and intermittent use of an eye patch.
  61. Glossopharyngeal Neuralgia
    Glossopharyngeal neuralgia is recurrent attacks of severe pain in the 9th cranial nerve distribution (posterior pharynx, tonsils, back of the tongue, middle ear). Diagnosis is clinical. Treatment is usually with carbamazepine or gabapentin.
  62. Craniocervical Junction Abnormalities
    Craniocervical junction abnormalities are congenital or acquired abnormalities of the occipital bone, foramen magnum, or first 2 cervical vertebrae that decrease the space for the lower brain stem and cervical cord. These abnormalities can result in neck pain; syringomyelia; cerebellar, lower cranial nerve, and spinal cord deficits; and vertebrobasilar ischemia. Diagnosis is by MRI or CT. Treatment often involves reduction, followed by stabilization via surgery or an external device.
  63. Movement and Cerebellar Disorders
    Voluntary movement requires interaction of the corticospinal (pyramidal) tracts, basal ganglia, and cerebellum (the center for motor coordination). The pyramidal tracts pass through the medullary pyramids to connect the cerebral cortex to lower motor centers of the brain stem and spinal cord. The basal ganglia (caudate nucleus, putamen, globus pallidus, subthalamic nucleus, and substantia nigra) form the extrapyramidal system. They are located deep in the forebrain and direct their output mainly rostrally through the thalamus to the cerebral cortex. Most neural lesions that cause movement disorders occur in the extrapyramidal system; thus, movement disorders are also called extrapyramidal disorders.
  64. Chorea, Athetosis, and Hemiballismus
    Chorea is nonrhythmic, jerky, rapid, nonsuppressible involuntary movements, mostly of distal muscles or the face; movements may merge imperceptibly into purposeful or semipurposeful acts that mask the involuntary movements. Athetosis is nonrhythmic, slow, writhing, sinuous movements predominantly in distal muscles, often alternating with postures of the proximal limbs to produce a continuous, flowing stream of movement. Hemiballismus is usually a unilateral, nonrhythmic, rapid, nonsuppressible, violent, flinging movement of the proximal arm.
  65. Dystonias
    Dystonias are sustained involuntary muscle contractions, often distorting body posture. Dystonias can be primary or secondary, and they can be generalized, focal, or segmental. Diagnosis is clinical. Treatment of generalized dystonia is often with a combination of anticholinergic drugs, muscle relaxants, and benzodiazepines. Treatment of focal or segmental dystonias is often with botulinum toxin; more generalized or refractory cases may benefit from surgery.
  66. Fragile X–Associated Tremor/Ataxia Syndrome (FXTAS)
    Fragile X–associated tremor/ataxia syndrome (FXTAS) is a genetic disorder affecting mostly men and causing tremor, ataxia, and dementia.
  67. Huntington's Disease
    Huntington's disease is an autosomal dominant disorder characterized by chorea and progressive cognitive deterioration, usually beginning in middle age. Diagnosis is by genetic testing. Treatment is supportive. First-degree relatives are encouraged to have genetic testing.
  68. Myoclonus
    Myoclonus is a brief, shocklike contraction of a muscle or group of muscles. Diagnosis is clinical and by selective testing. Treatment includes correction of reversible causes and sometimes oral drugs (eg, clonazepam, valproate).
  69. Parkinson's Disease
    Parkinson's disease is an idiopathic, slowly progressive, degenerative CNS disorder characterized by resting tremor, muscular rigidity, slow and decreased movement, and postural instability. Diagnosis is clinical. Treatment is with levodopa plus carbidopa, other drugs, and, for refractory symptoms, surgery.
  70. Progressive Supranuclear Palsy
    Progressive supranuclear palsy is a rare, degenerative CNS disorder causing loss of voluntary eye movements, bradykinesia, muscular rigidity with progressive axial dystonia, pseudobulbar palsy, and dementia.
  71. Tremor
    • Tremors are involuntary, rhythmic, alternating, or oscillatory movements of interrelated muscle groups. They typically involve the hands, head, facial structures, vocal cords, trunk, or legs. Tremors can be characterized by
    • Frequency of oscillation (rapid or slow)
    • Amplitude of movement (fine or coarse)
    • Movements or postures that evoke them (eg, rest, action, certain positions)
  72. Cerebellar Disorders
    • Cerebellar disorders have numerous causes, including congenital malformations, hereditary ataxias, and acquired conditions. Symptoms vary with the cause but typically include ataxia (impaired muscle coordination). Diagnosis is clinical and often by imaging and sometimes genetic testing. Treatment is usually supportive unless the cause is acquired and reversible.
    • The cerebellum has 3 parts:
    • Archicerebellum (vestibulocerebellum): It includes the flocculonodular lobe, which is located in the medial zone. It helps maintain equilibrium and coordinate eye, head, and neck movements; it is closely interconnected with the vestibular nuclei.
    • Midline vermis (paleocerebellum): It helps coordinate trunk and leg movements. Vermis lesions result in abnormalities of stance and gait.
    • Lateral hemispheres (neocerebellum): They control quick and finely coordinated limb movements, predominantly of the arms.
  73. Demyelinating Disorders
    Myelin sheaths cover many nerve fibers in the central and peripheral nervous system; they accelerate axonal transmission of neural impulses. Disorders that affect myelin interrupt nerve transmission; symptoms may reflect deficits in any part of the nervous system.
  74. Multiple Sclerosis (MS)
    Multiple sclerosis (MS) is characterized by disseminated patches of demyelination in the brain and spinal cord. Common symptoms include visual and oculomotor abnormalities, paresthesias, weakness, spasticity, urinary dysfunction, and mild cognitive impairment. Typically, neurologic deficits are multiple, with remissions and exacerbations gradually producing disability. Diagnosis is by history of remissions and exacerbations plus clinical signs, test results, lesions seen on MRI, or other criteria (depending on symptoms) to objectively demonstrate ≥ 2 separate neurologic abnormalities. Treatment includes corticosteroids for acute exacerbations, immunomodulatory drugs to prevent exacerbations, and supportive measures.
  75. Neuromyelitis Optica (Devic Disease)
    Neuromyelitis optica affects only the eyes and spinal cord. It causes acute optic neuritis, sometimes bilateral, plus demyelination of the cervical or thoracic spinal cord. Neuromyelitis optica was previously considered to be a variant of multiple sclerosis (MS) but is now recognized as a different disorder.
  76. Peripheral Nervous System Disorders
    • The peripheral nervous system refers to parts of the nervous system outside the brain and spinal cord. It includes the cranial nerves and spinal nerves from their origin to their end. The anterior horn cells, although technically part of the CNS, are sometimes discussed with the peripheral nervous system because they are part of the motor unit.
    • Motor neuron dysfunction results in muscle weakness or paralysis. Sensory neuron dysfunction results in abnormal or lost sensation. Some disorders are progressive and fatal.
  77. Disorders of Neuromuscular Transmission
    • Disorders of neuromuscular transmission affect the neuromuscular junction. They may involve
    • Postsynaptic receptors (eg, in myasthenia gravis)
    • Presynaptic release of acetylcholine (eg, in botulism)
    • Breakdown of acetylcholine within the synapse (eg, due to drugs or neurotoxic chemicals)
  78. Stiff-person syndrome
    The syndrome affects the CNS but has neuromuscular manifestations. It often occurs in patients with type 1 diabetes. It may be autoimmune and can occur as a paraneoplastic syndrome (most often with breast, lung, or colon cancer or with Hodgkin lymphoma). Autoantibodies against several proteins involved in GABA (γ-aminobutyric acid)-glycine synapses are present, affecting primarily inhibitory neurons that originate in the anterior horn of the spinal cord.
  79. Isaacs' syndrome
    This syndrome, generally thought to be a channelopathy, sometimes occurs as a paraneoplastic syndrome. It may also occur in other disorders (eg, myasthenia gravis, thymoma, cancer, amyloidosis) or can be inherited. Cause is unknown. Abnormalities are thought to originate in a peripheral nerve because they are abolished by curare but usually persist after general anesthesia.
  80. Guillain-Barré Syndrome (GBS)
    Guillain-Barré syndrome is an acute, usually rapidly progressive inflammatory polyneuropathy characterized by muscular weakness and mild distal sensory loss. Cause is thought to be autoimmune. Diagnosis is clinical. Treatment includes plasmapheresis, γ-globulin, and, for severe cases, mechanical ventilation.
  81. Hereditary Neuropathies
    Hereditary neuropathies include a variety of congenital degenerative peripheral neuropathies.
  82. Sensorimotor neuropathies
    • There are 3 main types (I, II, and III); all begin in childhood. Some less common types begin at birth and result in greater disability.
    • Types I and II (Charcot-Marie-Tooth disease, peroneal muscular atrophy) are the most common.
    • Type III (hypertrophic interstitial neuropathy, Dejerine-Sottas disease), a rare autosomal recessive disorder .
    In hereditary motor neuropathy (HNPP) with liability to pressure palsies, nerves become increasingly sensitive to pressure and stretch.
  84. Motor Neuron Disorders
    Motor neuron disorders (MNDs) are characterized by steady, relentless, progressive degeneration of corticospinal tracts, anterior horn cells, bulbar motor nuclei, or a combination. Symptoms vary in severity and may include muscle weakness and atrophy, fasciculations, emotional lability, and respiratory muscle weakness. Diagnosis involves nerve conduction velocity studies, electromyography, and exclusion of other disorders via MRI and laboratory tests. Treatment is supportive.
  85. Myasthenia Gravis
    Myasthenia gravis involves episodic muscle weakness and easy fatigability caused by autoantibody- and cell-mediated destruction of acetylcholine receptors. It is more common among young women but may occur at any age. Symptoms worsen with muscle activity and lessen with rest. Diagnosis is by antibody testing to acetylcholine receptor (AChR), electromyography, and IV edrophonium challenge, which briefly lessens the weakness. Treatment includes anticholinesterase drugs, immunosuppressants, corticosteroids, plasmapheresis, and possibly thymectomy.
  86. Nerve Root Disorders
    Nerve root disorders result in segmental radicular deficits (eg, pain or paresthesias in a dermatomal distribution, weakness of muscles innervated by the root). Diagnosis may require neuroimaging, electrodiagnostic studies, and systemic testing for underlying disorders. Treatment depends on the cause but includes symptomatic relief with NSAIDs and other analgesics.
  87. Peripheral Neuropathy
    Peripheral neuropathy is dysfunction of one or more peripheral nerves (the part of a spinal nerve distal to the root and plexus). It includes numerous syndromes characterized by varying degrees of sensory disturbances, pain, muscle weakness and atrophy, diminished deep tendon reflexes, and vasomotor symptoms, alone or in any combination. Initial classification is based on history and physical examination. Electromyography and nerve conduction velocity studies help localize the lesion and determine whether the pathophysiology is primarily axonal (often metabolic) or demyelinating (often autoimmune). Treatment is aimed mainly at the cause.
  88. Plexus Disorders
    Disorders of the brachial or lumbosacral plexus cause a painful mixed sensorimotor disorder of the corresponding limb.
  89. Spinal Muscular Atrophies
    Spinal muscular atrophies include several types of hereditary disorders characterized by skeletal muscle wasting due to progressive degeneration of anterior horn cells in the spinal cord and of motor nuclei in the brain stem. Manifestations may begin in infancy or childhood. They vary by the specific type and may include hypotonia; hyporeflexia; difficulty sucking, swallowing, and breathing; unmet developmental milestones; and, in more severe types, very early death. Diagnosis is by genetic testing. Treatment is supportive.
  90. Thoracic Outlet Compression Syndromes
    Thoracic outlet compression syndromes are a group of poorly defined disorders characterized by pain and paresthesias in a hand, the neck, a shoulder, or an arm. They appear to involve compression of the brachial plexus (and perhaps the subclavian vessels) as these structures traverse the thoracic outlet. Diagnostic techniques have not been established. Treatment includes physical therapy, analgesics, and, in severe cases, surgery.
  91. Acute Transverse Myelitis
    Acute transverse myelitis is acute inflammation of gray and white matter in one or more adjacent spinal cord segments, usually thoracic. Causes include multiple sclerosis, infections, autoimmune or postinfectious inflammation, vasculitis, and certain drugs. Symptoms include bilateral motor, sensory, and sphincter deficits below the level of the lesion. Diagnosis is usually by MRI, CSF analysis, and blood tests. IV corticosteroids and plasma exchange may be helpful early. Otherwise, treatment is supportive measures and correction of any causes.
  92. Arteriovenous Malformations
    Arteriovenous malformations (AVMs) in or around the spinal cord can cause cord compression, ischemia, parenchymal hemorrhage, subarachnoid hemorrhage, or a combination. Symptoms may include gradually progressive, ascending, or waxing and waning segmental neurologic deficits; radicular pain; and sudden back pain with sudden segmental neurologic deficits. Diagnosis is by MRI. Treatment is with surgery or stereotactic radiosurgery and may include angiographic embolization.
  93. Cervical Spondylosis and Spondylotic Cervical Myelopathy
    Cervical spondylosis is osteoarthritis of the cervical spine causing stenosis of the canal and sometimes cervical myelopathy due to encroachment of bony osteoarthritic growths (osteophytes) on the lower cervical spinal cord, sometimes with involvement of lower cervical nerve roots (radiculomyelopathy).
  94. Hereditary Spastic Paraparesis
    Hereditary spastic paraparesis is a group of rare hereditary disorders characterized by progressive, spinal, nonsegmental, spastic leg paresis, sometimes with intellectual disability, seizures, and other extraspinal deficits.
  95. Spinal Cord Infarction
    Spinal cord infarction usually results from ischemia originating in an extravertebral artery. Symptoms include sudden and severe back pain, bilateral flaccid limb weakness, and loss of sensation, particularly pain and temperature. Diagnosis is by MRI. Treatment is generally supportive.
  96. Spinal Cord Compression
    Various lesions can compress the spinal cord, causing segmental sensory, motor, reflex, and sphincter deficits. Diagnosis is by MRI. Treatment is directed at relieving compression.
  97. Spinal Epidural Abscess
    A spinal epidural abscess is an accumulation of pus in the epidural space that can mechanically compress the spinal cord.
  98. Spinal Subdural or Epidural Hematoma
    A spinal subdural or epidural hematoma is an accumulation of blood in the subdural or epidural space that can mechanically compress the spinal cord.
  99. Syrinx
    A syrinx is a fluid-filled cavity within the spinal cord (syringomyelia) or brain stem (syringobulbia). Predisposing factors include craniocervical junction abnormalities, spinal cord trauma, and spinal cord tumors. Symptoms include flaccid weakness of the hands and arms and deficits in pain and temperature sensation in a capelike distribution over the back and neck; light touch and position and vibration sensation are not affected. Diagnosis is by MRI. Treatment includes correction of the cause and surgical procedures to drain the syrinx or otherwise open CSF flow.
  100. Tropical Spastic Paraparesis/HTLV-1–Associated Myelopathy
    Tropical spastic paraparesis/HTLV-1–associated myelopathy is a slowly progressive viral immune-mediated disorder of the spinal cord caused by the human T-lymphotropic virus 1 (HTLV-1). It causes spastic weakness of both legs. Diagnosis is by serologic and PCR tests of serum and CSF. Treatment includes supportive care and possibly immunosuppressive therapies.
  101. Intracranial Tumors
    Intracranial tumors may involve the brain or other structures (eg, cranial nerves, meninges). The tumors usually develop during early or middle adulthood but may develop at any age; they are becoming more common among the elderly. Brain tumors are found in about 2% of routine autopsies.
  102. Gliomas
    Gliomas are primary tumors that originate in brain parenchyma. Symptoms and diagnosis are similar to those of other brain tumors. Treatment involves surgical excision, radiation therapy, and, for some tumors, chemotherapy. Excision rarely cures.
  103. Meningiomas
    Meningiomas are benign tumors of the meninges that can compress adjacent brain tissue. Symptoms depend on the tumor's location. Diagnosis is by MRI with contrast agent. Treatment may include excision, stereotactic radiosurgery, and sometimes radiation therapy.
  104. Pineal Region Tumors
    Most pineal region tumors are germ cell tumors.
  105. Pituitary Tumors
    Most pituitary tumors are adenomas. Symptoms include headache and endocrinopathies; endocrinopathies result when the tumor produces hormones or destroys hormone-producing tissue. Diagnosis is by MRI. Treatment includes correction of any endocrinopathy and surgery, radiation therapy, or dopaminergic agonists.
  106. Primary Brain Lymphomas
    Primary brain lymphomas originate in neural tissue and are usually B-cell tumors. Diagnosis requires neuroimaging and sometimes CSF analysis (including Epstein-Barr titers,) or brain biopsy. Treatment includes corticosteroids, chemotherapy, and radiation therapy.
  107. Spinal Cord Tumors
    Spinal cord tumors may develop within the spinal cord parenchyma, directly destroying tissue, or outside the cord parenchyma, often compressing the cord or nerve roots. Symptoms include progressive back pain and neurologic deficits referable to the spinal cord or spinal nerve roots. Diagnosis is by MRI. Treatment may include corticosteroids, surgical excision, and radiation therapy.
Card Set:
definitions neuro mm
2011-09-05 02:56:27
medical clinical definitions neurology mm

definitions neuro mm
Show Answers: