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  1. <Medical Topics
    Neurology
    Approach to the Neurologic Patient
    • Approach to the Neurologic Patient
      • History
      • Physical Examination and Testing
    • Neurotransmission
      • Propagation
      • Transmission
      • Receptors
      • Major Neurotransmitters and Receptors
        • Glutamate and aspartate
        • Gamma-aminobutyric acid
        • Serotonin
        • Acetylcholine
        • Dopamine
        • Norepinephrine
        • Endorphins and enkephalins
        • Other neurotransmitters
      • Disorders Associated With Defects in Neurotransmission
    Symptoms of Neurologic Disorders
    • Memory Loss
      • Etiology
        • Etiology reference
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
        • Evaluation references
      • Treatment
        • General measures
        • Patient safety
        • Environmental measures
        • Medications
        • Treatment reference
      • Key Points
      • More Information
    • Muscle Cramps
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
      • Treatment
      • Prevention
        • Prevention references
      • Key Points
    • Numbness
      • Pathophysiology
        • Anatomy
        • Mechanisms
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
      • Treatment
      • Key Points
    • Weakness
      • Pathophysiology
      • Etiology
        • Fatigue
      • Evaluation
        • History
        • Physical examination
        • General examination
        • Red flags
        • Interpretation of findings
        • Determination of a specific causative disorder
        • Testing
      • Treatment
      • Geriatrics Essentials: Weakness
      • Key Points
    • Introduction to Symptoms of Neurologic Disorders
    Neurologic Examination
    • How To Assess Reflexes
      • Deep tendon reflexes
      • Pathologic reflexes
      • Other reflexes
    • How To Assess Mental Status
    • How To Assess the Cranial Nerves
      • Cranial nerve I
      • Cranial nerve II
      • Cranial nerves III, IV, VI
      • Cranial nerve V
      • Cranial nerve VII
      • Cranial nerve VIII
      • Cranial nerves IX and X
      • Cranial nerve XI
      • Cranial nerve XII
      • Reference
    • How To Assess the Motor System
    • How To Assess Muscle Strength
    • How To Assess Gait, Stance, and Coordination
    • How To Assess Sensation
    • How To Assess the Autonomic Nervous System
    • Cerebrovascular Examination
    • Introduction to the Neurologic Examination
    Neurologic Tests and Procedures
    • Lumbar Puncture
      • Lumbar puncture procedure
      • CSF color
      • CSF cell count and glucose and protein levels
      • CSF staining, testing, and culture
      • References
    • Computed Tomography in Neurologic Disorders
    • Electroencephalography
    • Electromyography and Nerve Conduction Studies
      • Electromyography
      • Nerve conduction studies
    • Measurement of Evoked Responses
    • Nerve and Muscle Biopsy
    • Other Neurologic Imaging Studies
      • Cerebral catheter angiography
      • Duplex Doppler ultrasound
      • Echoencephalography
      • Myelography
    • Magnetic Resonance Imaging in Neurologic Disorders
      • References
    Autonomic Nervous System
    • Overview of the Autonomic Nervous System
      • Anatomy
        • Sympathetic system
        • Parasympathetic system
      • Physiology
      • Etiology of Autonomic Insufficiency
        • Etiology reference
      • Evaluation of Autonomic Insufficiency
        • History
        • Physical examination
        • Laboratory testing
        • Reference
    • Autonomic Neuropathies
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis references
      • Treatment
        • Treatment references
      • Key Points
    • Horner Syndrome
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Multiple System Atrophy
      • General references
      • Etiology
      • Symptoms and Signs
        • Parkinsonian symptoms
        • Cerebellar abnormalities
        • Autonomic symptoms
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Key Points
    • Pure Autonomic Failure
      • General references
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
      • Key Points
    Brain Infections
    • Introduction to Brain Infections
      • References
    • Brain Abscess
      • Etiology
        • Etiology reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Encephalitis
      • Etiology
        • Primary viral infection
        • Immunologic reaction
        • Etiology references
      • Pathophysiology
        • Pathophysiology reference
      • Symptoms and Signs
      • Diagnosis
        • MRI
        • CSF testing
        • Brain biopsy
        • Diagnosis references
      • Treatment
      • Prognosis
        • Prognosis reference
      • Key Points
    • Helminthic Brain Infections
      • Neurocysticercosis
      • Other helminthic infections
      • References
    • Progressive Multifocal Leukoencephalopathy (PML)
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Rabies
      • General references
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Prevention
        • Preexposure rabies prophylaxis
        • Postexposure rabies prophylaxis
        • Prevention references
      • Key Points
    • Intracranial Epidural Abscess and Subdural Empyema
      • Etiology
        • Complications
      • Symptoms and Signs
        • Symptoms and signs reference
      • Diagnosis
      • Treatment
      • Key Points
    Coma and Impaired Consciousness
    • Overview of Coma and Impaired Consciousness
      • Pathophysiology
        • Pathophysiology references
      • Etiology
      • Symptoms and Signs
      • Diagnosis
        • History
        • General physical examination
        • Neurologic examination
        • Eye examination
        • Respiratory patterns
        • Testing
        • Diagnosis references
      • Treatment
        • Endotracheal intubation
        • Intracranial pressure control
        • Long-term care
        • Treatment references
      • Prognosis
        • Prognosis references
      • Geriatrics Essentials
      • Key Points
    • Vegetative State and Minimally Conscious State
      • General reference
      • Symptoms and Signs
        • Vegetative state
        • Minimally conscious state
        • Symptoms and signs references
      • Diagnosis
      • Treatment
        • Treatment references
      • Prognosis
        • Vegetative state
        • Minimally conscious state
        • Prognosis reference
      • Key Points
    • Locked-In Syndrome
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Treatment reference
      • Prognosis
    • Brain Death
      • Diagnosis
        • Diagnosis reference
      • Prognosis
    • Brain Herniation
      • Transtentorial herniation
      • Subfalcine herniation
      • Central herniation
      • Upward transtentorial herniation
      • Tonsillar herniation
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    Craniocervical Junction Abnormalities
    • Craniocervical Junction Abnormalities
      • Etiology
        • Congenital
        • Acquired
      • Symptoms and Signs
      • Diagnosis
        • Neuroimaging
      • Treatment
        • Bone disease
      • Key Points
    Delirium and Dementia
    • Overview of Delirium and Dementia
      • General references
    • Delirium
      • General references
      • Etiology
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Mental status examination
        • History
        • Physical examination
        • Testing
        • Diagnosis references
      • Treatment
        • Management of agitation
        • Treatment references
      • Prognosis
        • Prognosis references
      • Prevention
      • Geriatrics Essentials
      • Key Points
    • Dementia
      • Etiology
        • Etiology references
      • Symptoms and Signs
        • Early (mild) dementia symptoms
        • Intermediate (moderate) dementia symptoms
        • Late (severe) dementia symptoms
        • Symptoms and signs reference
      • Diagnosis
        • Clinical criteria
        • Assessment of cognitive function
        • Laboratory testing
        • Neuroimaging
        • Diagnosis references
      • Treatment
        • Patient safety
        • Environmental measures
        • Medications
        • Caregiver assistance
        • Treatment references
      • Prognosis
        • End-of-life issues
        • Prognosis references
      • Key Points
      • More Information
    • Behavioral and Psychologic Symptoms of Dementia
      • Etiology
      • Evaluation
        • Evaluation reference
      • Treatment
        • Environmental measures
        • Caregiver support
        • Use of medications
        • Antipsychotics
        • Other medications
      • Key Points
      • More Information
    • Chronic Traumatic Encephalopathy (CTE)
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • End-of-life issues
      • Prevention
    • Alzheimer Disease
      • General reference
      • Etiology
        • Etiology reference
      • Pathophysiology
        • Pathophysiology references
      • Symptoms and Signs
      • Diagnosis
        • Differential diagnosis
      • Diagnosis references
      • Treatment
        • Symptomatic treatment of Alzheimer disease
        • Disease-modifying treatment of Alzheimer disease
        • Treatment references
      • Prognosis
        • End-of-life issues
        • Prognosis reference
      • Prevention
        • Prevention reference
      • Key Points
      • More Information
    • Vascular Cognitive Impairment and Dementia
      • Etiology
        • Etiology reference
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
      • Prognosis
        • End-of-life issues
        • Prognosis reference
      • Key Points
    • Dementia with Lewy Bodies and Parkinson Disease Dementia
      • Reference
      • Symptoms and Signs
        • Dementia with Lewy bodies
        • Parkinson disease dementia
      • Diagnosis
      • Treatment
      • Medications
      • End-of-life issues
      • Key Points
    • Frontotemporal Dementia (FTD)
      • Symptoms and Signs
        • Behavioral (frontal) variant FTD
        • Primary progressive aphasia
      • Diagnosis
      • Treatment
      • Prognosis
        • End-of-life issues
    • Normal Pressure Hydrocephalus
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    Demyelinating Disorders
    • Overview of Demyelinating Disorders
    • Multiple Sclerosis (MS)
      • General references
      • Pathophysiology
      • Symptoms and Signs
        • Cranial nerves
        • Motor
        • Cerebellar
        • Sensory
        • Spinal cord
      • Diagnosis
        • Additional testing
        • Diagnosis references
      • Treatment
        • Treatment of exacerbations and relapses
        • Disease-modifying therapies
        • Rehabilitative care and symptom management
        • Symptom control
        • Treatment references
      • Prognosis
        • Prognosis references
      • Key Points
    • Neuromyelitis Optica Spectrum Disorder (NMOSD)
      • General reference
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Key Points
    Function and Dysfunction of the Cerebral Lobes
    • Overview of Cerebral Function
      • Frontal lobes
      • Parietal lobes
      • Temporal lobes
      • Occipital lobes
      • Insula
      • Limbic lobe
      • Pathophysiology
        • Recovery
        • Cerebral dysfunction syndromes
      • Diagnosis
    • Agnosia
      • Etiology
      • Types
        • Reference
      • Diagnosis
      • Treatment
      • Prognosis
      • Key Points
    • Amnesias
      • Etiology
      • Diagnosis
      • Treatment
      • Key Points
    • Aphasia
      • Etiology
      • Types
      • Symptoms and Signs
        • Wernicke aphasia
        • Broca aphasia
      • Diagnosis
      • Treatment
        • Treatment reference
      • Prognosis
      • Key Points
    • Apraxia
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Prognosis
      • Key Points
    • COVID-Related Neuropsychiatric Manifestations
      • Pathophysiology
        • Acute phase
        • Chronic phase
        • Pathophysiology references
      • Symptoms and Signs
        • Acute neuropsychiatric symptoms
        • Post-recovery and chronic neuropsychiatric symptoms
        • Symptoms and signs references
      • Diagnosis
      • Treatment
        • Treatment references
      • Prognosis
      • Key Points
    • Transient Global Amnesia
      • References
      • Etiology
        • Etiology reference
      • Symptoms and Signs
      • Symptoms and signs references
      • Diagnosis
      • Treatment
      • Prognosis
      • Prognosis reference
      • Key Points
    Headache
    • Approach to the Patient With Headache
      • Pathophysiology
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
      • Treatment
      • Key Points
    • Cluster Headache
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Idiopathic Intracranial Hypertension
      • References
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Migraine
      • Epidemiology
        • Epidemiology references
      • Pathophysiology
        • Pathophysiology references
      • Symptoms and Signs
        • Chronic migraine
        • Other symptoms
      • Diagnosis
      • Treatment
        • Acute attacks
        • Intractable attacks
        • Chronic migraines
        • Neuromodulatory treatments
        • Treatment references
      • Prognosis
        • Prognosis reference
      • Prevention
        • Prevention references
      • Key Points
    • Postlumbar Puncture and Other Low–Pressure Headaches
      • Diagnosis
      • Treatment
        • Treatment reference
    • Tension-Type Headache
      • Symptoms and Signs
      • Diagnosis
      • Treatment
    • Short-Lasting Unilateral Neuralgiform Headache With Conjunctival Injection and Tearing (SUNCT)
      • Diagnosis
      • Treatment
        • Reference
    • Medication Overuse Headache
      • Etiology
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment reference
      • Prognosis
    How To Do Lumbar Puncture
    • How To Do Lumbar Puncture
      • Indications
      • Contraindications
      • Complications
      • Equipment
      • Additional Considerations
      • Relevant Anatomy
      • Positioning
      • Step-by-Step Description of Procedure
        • Identify and prepare the site
        • Insert the spinal needle
        • Measure CSF pressure
        • Collect CSF
        • Conclude the procedure
      • Aftercare
      • Warnings and Common Errors
      • Tricks and Tips
      • References
    Meningitis
    • Overview of Meningitis
      • Symptoms and Signs
      • Diagnosis
      • Treatment
    • Acute Bacterial Meningitis
      • Pathophysiology
      • Etiology
        • Age
        • Route of entry
        • Immune status
      • Symptoms and Signs
      • Atypical presentations in adults
      • Symptoms and signs reference
      • Diagnosis
        • Lumbar puncture
        • Other tests
        • Diagnosis references
      • Treatment
        • Antibiotics
        • Corticosteroids
        • Other measures
        • Treatment reference
      • Prognosis
        • Prognosis reference
      • Prevention
        • Vaccination
        • Physical measures
        • Chemoprophylaxis
      • Key Points
      • More Information
    • Viral Meningitis
      • Etiology
        • Causes reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Noninfectious Meningitis
    • Recurrent Meningitis
      • Recurrent viral meningitis
      • Recurrent acute bacterial meningitis
      • Other recurrent meningitides
      • Reference
    • Subacute and Chronic Meningitis
      • Tuberculous meningitis
      • Meningitis due to spirochetes
      • Syphilitic meningitis
      • Cryptococcal meningitis
      • Fungal meningitis that develops after epidural methylprednisolone injection
      • Other fungal meningitides
      • Chronic meningitis in patients with HIV infection
      • Carcinomatous meningitis
      • Other causes of chronic meningitis
      • Chronic idiopathic meningitis
      • References
      • Diagnosis
      • Treatment
      • Key Points
    Movement and Cerebellar Disorders
    • Chorea, Athetosis, and Hemiballismus
    • Fragile X–Associated Tremor/Ataxia Syndrome (FXTAS)
      • General reference
      • Symptoms and Signs
        • Symptoms and signs reference
      • Diagnosis
      • Treatment
      • Treatment references
      • Key Points
    • Huntington Disease
      • General reference
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment reference
      • Key Points
    • Myoclonus
      • Classification of myoclonus
      • Classification reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Parkinson Disease
      • General references
      • Pathophysiology
      • Etiology
        • Etiology references
      • Symptoms and Signs
        • Symptoms and signs references
      • Diagnosis
      • Treatment
        • Levodopa
        • Amantadine
        • Dopamine agonists
        • Selective MAO-B inhibitors
        • Anticholinergic medications
        • Catechol O-methyltransferase (COMT) inhibitors
        • Surgery
        • High-intensity focused ultrasound (HIFU)
        • Physical and lifestyle measures
        • Caregiver and end-of-life issues
        • Treatment references
      • Key Points
    • Progressive Supranuclear Palsy (PSP)
      • Symptoms and Signs
        • Symptoms and signs references
      • Diagnosis
        • Diagnosis references
      • Treatment
      • Key Points
    • Tremor
      • Pathophysiology
        • Classification
      • Etiology
        • Physiologic tremor
        • Pathologic (nonphysiologic) tremor
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
      • Treatment
        • Physiologic tremors
        • Essential tremors
        • Cerebellar tremors
        • Parkinsonian tremors
        • Medication-refractory tremor
        • Functional (psychogenic) tremor
        • Treatment reference
      • Geriatrics Essentials
      • Key Points
    • Cerebellar Disorders
      • General reference
      • Etiology
        • Congenital malformations
        • Hereditary ataxias
        • Acquired conditions
        • Etiology references
      • Diagnosis
      • Treatment
        • Treatment references
    • Dystonias
      • Classification
        • Primary generalized dystonia (DYT1 dystonia)
        • Dopa-responsive dystonia
        • Focal dystonias
        • Segmental dystonias
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Cervical Dystonia
      • Symptoms and Signs
        • Symptoms and signs references
      • Diagnosis
        • Diagnosis references
      • Treatment
        • Medications
        • Surgery
      • Treatment references
      • Key Points
    • Secondary and Atypical Parkinsonism
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Overview of Movement and Cerebellar Disorders
      • Classification
        • Hyperkinetic disorders
    Neuro-Ophthalmologic and Cranial Nerve Disorders
    • Overview of Neuro-Ophthalmologic and Cranial Nerve Disorders
      • Diagnosis
      • Treatment
    • Conjugate Gaze Palsies
      • Horizontal gaze palsies
      • Vertical gaze palsies
      • Downward gaze palsies
      • Key Points
    • Internuclear Ophthalmoplegia
      • One-and-a-half syndrome
      • Key Points
    • Third Cranial Nerve (Oculomotor) Disorders
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Fourth Cranial Nerve (Trochlear) Palsy
      • Treatment
    • Sixth Cranial Nerve (Abducens) Palsy
      • Etiology
        • Etiology reference
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
      • Key Points
    • Trigeminal Neuralgia
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Hemifacial Spasm
    • Facial Nerve Palsy
      • Etiology
        • Etiology reference
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Prognosis
      • Key Points
    • Glossopharyngeal Neuralgia
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    Pain
    • Overview of Pain
      • References
      • Pathophysiology and Classification
        • Pain processing: transduction, transmission, modulation, and perception
        • Pathophysiology and classification references
      • Key Points
    • Evaluation of Pain
      • Pain severity
      • Patients with dementia or aphasia
      • Patients receiving neuromuscular blockade
      • References
      • Key Points
    • Treatment of Pain
      • References
      • Nonopioid Analgesics
        • Nonopioid analgesic references
      • Opioid Analgesics
        • Route of administration
        • Dosing and titration
        • Adverse effects
        • Opioid misuse, diversion, and abuse
        • Opioid antagonists
        • Opioid analgesics references
      • Adjuvant Analgesics
      • Adjuvant analgesics reference
      • Nonpharmacologic Pain Treatments
        • Nerve Blocks and Neuraxial Injections
        • Neuromodulation
        • Joint Injections
        • Advanced Minimally Invasive Procedures
        • Other Interventional Techniques
      • Geriatrics Essentials
        • Nonsteroidal anti-inflammatory drugs (NSAIDs)
        • Opioids
      • Key Points
    • Chronic Widespread (Centralized) Pain
      • Fibromyalgia
      • Fibromyalgia references
      • Treatment
        • Medications
        • Nonpharmacologic treatments
        • Treatment references
    • Neuropathic Pain
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Complex Regional Pain Syndrome (CRPS)
      • Reference
      • Etiology
        • Etiology reference
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Prognosis
      • Prevention
        • Prevention references
      • Key Points
    Peripheral Nervous System and Motor Unit Disorders
    • Overview of Peripheral Nervous System Disorders
      • Anatomy
      • Physiology
      • Etiology
      • Pathophysiology
        • Damage
        • Recovery
      • Evaluation
        • Clinical evaluation
        • Testing
      • Treatment
      • Key Points
    • Disorders of Neuromuscular Transmission
      • Eaton-Lambert syndrome
      • Botulism
      • Medications or toxic chemicals
    • Guillain-Barré Syndrome (GBS)
      • Etiology
        • Etiology references
      • Symptoms and Signs
        • Symptoms and signs references
      • Diagnosis
        • Differential diagnosis
        • Testing
      • Treatment
        • Treatment references
      • Prognosis
        • Prognosis references
      • Key Points
    • Hereditary Neuropathies
      • Motor and sensory neuropathies
      • Motor and sensory neuropathies references
      • Sensory and autonomic neuropathies
      • Diagnosis
      • Treatment
      • Key Points
    • Amyotrophic Lateral Sclerosis (ALS) and Other Motor Neuron Diseases (MNDs)
      • General reference
      • Symptoms and Signs
        • Amyotrophic lateral sclerosis (ALS)
        • Progressive bulbar palsy and progressive pseudobulbar palsy
        • Progressive muscular atrophy
        • Primary lateral sclerosis
        • Symptoms and signs reference
      • Diagnosis
        • Differential diagnosis
        • Testing
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Key Points
    • Myasthenia Gravis
      • Abnormal antibodies
      • Uncommon forms
      • General references
      • Symptoms and Signs
        • Symptoms and signs references
      • Diagnosis
        • Bedside testing
        • Antibody testing and electromyography
        • Further testing
        • Diagnosis references
      • Treatment
        • Symptomatic treatment
        • Immunomodulating treatment
        • Treatment references
      • Key Points
    • Nerve Root Disorders
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Peripheral Neuropathy
    • Brachial Plexus and Lumbosacral Plexus Disorders
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Spinal Muscular Atrophies (SMAs)
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Key Points
    • Thoracic Outlet Compression Syndromes (TOS)
      • General reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Isaacs Syndrome
      • Symptoms and Signs
      • Diagnosis
        • Diagnosis reference
      • Treatment
        • Treatment references
      • Key Points
    • Stiff-Person Syndrome
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Mononeuropathies
      • Etiology
      • Symptoms and Signs
        • Carpal tunnel syndrome
        • Peroneal nerve palsy
        • Radial nerve palsy
        • Ulnar nerve palsy
      • Diagnosis
      • Treatment
      • Key Points
    • Multiple Mononeuropathy
    • Polyneuropathy
      • Symptoms and Signs
        • Myelin dysfunction
        • Vasa nervorum compromise
        • Axonopathy
      • Diagnosis
        • Electrodiagnostic tests
        • Laboratory tests
      • Treatment
      • Key Points
    • Hereditary Motor Neuropathy With Liability to Pressure Palsies (HNPP)
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    Prion Diseases
    • Overview of Prion Diseases
      • Transmission of prion diseases
      • Transmission references
      • Treatment
      • Prevention
    • Creutzfeldt-Jakob Disease (CJD)
      • Variant CJD (vCJD)
      • References
      • Symptoms and Signs
        • Symptoms and signs reference
      • Diagnosis
        • Diagnosis references
      • Treatment
      • Prognosis
      • Prevention
      • Key Points
    • Gerstmann-Sträussler-Scheinker Disease (GSS)
      • Reference
    • Fatal Insomnia
      • Reference
    • Prion Disease Associated With Diarrhea and Autonomic Neuropathy
      • Reference
    • Variably Protease-Sensitive Prionopathy (VPSPr)
      • Reference
    • Kuru
      • Reference
    Seizure Disorders
    • Seizure Disorders
      • Definitions
      • General reference
      • Etiology
        • Etiology references
      • Classification
        • Generalized-onset seizures
        • Focal-onset seizures
        • Unknown (whether focal or generalized) seizures
        • Classification reference
      • Symptoms and Signs
        • Focal-onset seizures
        • Generalized-onset seizures
        • Status epilepticus
        • Sudden unexpected death in epilepsy
        • Symptoms and signs references
      • Diagnosis
        • History
        • Physical examination
        • Testing
        • Diagnosis reference
      • Treatment
        • General measures
        • Generalized convulsive status epilepticus
        • Dravet syndrome
        • Posttraumatic seizures
        • Long-term antiseizure therapy
        • Surgery
        • Vagus nerve stimulation
        • Brain responsive neurostimulation
        • Treatment references
      • Prognosis
        • Prognosis references
      • Key Points
    • Antiseizure Medications
      • General references
      • Principles of Long-Term Treatment
      • Choice of Medication for Long-Term Treatment
        • Adverse effects
        • Antiseizure medication use during pregnancy
        • Choice of medication for long-term treatment reference
    Sleep and Wakefulness Disorders
    • Approach to the Patient With a Sleep or Wakefulness Disorder
      • Pathophysiology
      • Etiology
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
        • Evaluation references
      • Treatment
        • Cognitive-behavioral therapy
        • Hypnotics
        • Other medications and substances used to treat insomnia
        • Treatment references
      • Key Points
    • Insomnia and Excessive Daytime Sleepiness (EDS)
      • Inadequate sleep hygiene
      • Adjustment insomnia
      • Psychophysiologic insomnia
      • Insomnia related to physical disorders
      • Insomnia related to mental disorders
      • Insufficient sleep syndrome (sleep deprivation)
      • Drug-related sleep disorders
      • Reference
    • Narcolepsy
      • References
      • Symptoms and Signs
        • Excessive daytime sleepiness
        • Cataplexy
        • Sleep paralysis
        • Hypnagogic or hypnopompic hallucinations
        • Disturbed nocturnal sleep
        • Symptoms and signs reference
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Parasomnias
      • Somnambulism
      • Sleep (Night) Terrors
      • Nightmares
      • Rapid Eye Movement (REM) Sleep Behavior Disorder
      • Sleep-Related Leg Cramps
        • References
    • Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS)
      • References
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment references
      • Key Points
    • Idiopathic Hypersomnia
      • Diagnosis
      • Treatment
        • Treatment reference
    • Snoring
      • Reference
      • Pathophysiology
      • Etiology
        • Primary snoring
        • Sleep-disordered breathing
        • Complications
        • Risk factors
      • Evaluation
        • History
        • Physical examination
        • Red flags
        • Interpretation of findings
        • Testing
      • Treatment
        • General measures
        • Oral appliances
        • Continuous positive airway pressure (CPAP)
        • Surgery
        • Treatment references
      • Key Points
    • Circadian Rhythm Sleep Disorders
      • Circadian rhythm sleep disorder, jet lag type (jet lag disorder)
      • Circadian rhythm sleep disorder, shift work type (shift work disorder)
      • Circadian rhythm sleep disorder, altered sleep phase types
      • References
    Spinal Cord Disorders
    • Overview of Spinal Cord Disorders
      • Anatomy
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
    • Acute Transverse Myelitis
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Prognosis
        • Prognosis references
      • Key Points
    • Spinal Cord Arteriovenous Malformations (AVMs)
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Cervical Spondylosis and Spondylotic Cervical Myelopathy
      • Symptoms and Signs
        • Symptoms and signs reference
      • Diagnosis
      • Treatment
      • Key Points
    • Hereditary Spastic Paraplegia
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Spinal Cord Infarction
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Spinal Cord Compression
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Spinal Epidural Abscess
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Spinal Subdural or Epidural Hematoma
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Syrinx of the Spinal Cord or Brain Stem
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • HTLV-1–Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP)
      • Reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Cauda Equina Syndrome
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Spinal Cord Autonomic Dysreflexia
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Prevention
        • Prevention references
      • Key Points
    • Subacute Combined Degeneration
    Stroke
    • Overview of Stroke
      • Risk factors
      • References
      • Symptoms and Signs
        • Complications
      • Evaluation
        • Testing
      • Treatment
        • Treatment references
      • Prognosis
        • Prognosis reference
    • Ischemic Stroke
      • Etiology
        • Cryptogenic stroke
        • Cardioembolism
        • Lacunar infarcts
        • Large-vessel atherosclerosis
        • Other causes
        • Etiology references
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
        • Brain assessment
        • Cardiac causes
        • Vascular causes
        • Blood-related causes
        • Diagnosis reference
      • Treatment
        • Acute stroke treatment
        • Long-term stroke treatment
        • Treatment references
      • Prognosis
      • Key Points
    • Intracerebral Hemorrhage
      • Etiology
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Key Points
    • Subarachnoid Hemorrhage
      • Etiology
      • Pathophysiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
        • Treatment reference
      • Prognosis
        • Prognosis reference
      • Key Points
    • Brain Aneurysms
      • General reference
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
    • Cerebral Arteriovenous Malformations (AVMs)
      • Diagnosis
      • Treatment
        • Treatment reference
    • Transient Ischemic Attack
      • Etiology
      • Symptoms and Signs
      • Diagnosis
      • Treatment
      • Key Points
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