Neuropathic Pain Syndromes Complex Regional Pain Syndrome Type I (Reflex Sympathetic Dystrophy) Initial noxious event involving distal extremity, pain disproportionate to injury, not limited to single nerve distribution. Associated with edema, changes in skin blood flow.
Neuropathic Pain Syndromes Sequela of injury to nerve or major branch (esp. median, sciatic, tibial, and ulnar nerves). Due to thalamic infarct or other lesion. Hemi-anesthesia followed by gradual return of sensory function and pain. Pain contra-lateral to lesion. Complex Regional Pain Syndrome Type 2 (Causalgia) Thalamic Pain: Dejerine-Roussy Syndrome
Tension headache Dull, bilateral, band like, chronic in course and usually related to stress. Tx: NSAID, rule out Major Depression
Migraine: at least five episodes of Episodic Headache lasting four to seventy two hours Unilateral Throbbing Worsened by movement Moderate or Severe Nausea or vomiting Photophobia and phonophobia Any two of:Any one of:
Cluster Headache M/F 6:1 Unilateral stabbing headache Ipsilateral lacrimation and nasal congestion with rhinorrhea Usually triggered by alcohol use. Treatment: 100% Oxygen (“Air Supply”)
Cluster Headache Rare Disorder ( % of population) Age of onset 20’s-30’s Clinical features: Excruciatingly severe, retro-orbital pain. Radiates to temple, teeth, neck. Last minutes. Ipsilateral autonomic features, pacing, nocturnal attacks often awaken them. Triggers: Alcohol, Nitroglycerin. Cycles usually occur spring and fall and last 4-12 weeks.
Subdural, Epidural and Subarachnoid Hemorrhages Brain Hemorrhages
Subdural Hematoma Suspect in older patient with new-onset headache Follows head trauma Tearing of bridging veins Extra-axial mass causes focal findings Waxing and Waning mental status “Concave on CT”
Epidural Hematoma Between bone and dura Associated skull fracture in 85% of adults Middle meningeal artery tear Brief LOC, initial lucid period then acute deterioration “Convex on CT”
Subarachnoid Hemorrhage Cause: Rupture of aneurysm or AV malformation. Clinical feature: sudden onset of “worst headache of my life” Studies: CT scan. LP will show blood and Xanthochromia (yellow heme pigment) Tx: Clip aneurysm “Athena and Zeus”
Subarachnoid Hemorrhage Occipito-nuchal Sentinel bleeds Most common cause? Trauma
Alzheimer’s Disease Extracellular deposition of amyloid-beta protein, intracellular neurofibrillary tangles, and loss of neurons. CT: Atrophy, ventricular dilatation Treatment:
CJD vs. AD CJDAD CourseSix months (rapid)Insidious (years to decades) Physical findingsMyoclonus EEGPeriodic complexes, burst- suppression Slowing of background CSF protein (>90%), some false + PathologySpongiform changesPlaques and tangles TransmissibilityPerson to person and person to animal Non-transmissable
Huey, Dewey and…
…..Lewy Body Dementia 2 nd commonest cause of degenerative dementia Progressive cognitive impairment Spontaneous onset Parkinson’s symptoms Extreme neuroleptic sensitivity, Sleep problems, V/H
Pick’s disease Personality change Decline in function Poor social judgment Inappropriate Pathology: Prominent fronto-temporal atrophy, neuron cell inclusions, clustered cytoskeletal elements
“NPH wouldn’t do that!” Triad: an imbalanced, wide-based walk or “shuffle,” urinary incontinence and MEMORY PROBLEMS. Dementia predominantly frontal lobe in nature, with apathy, dullness in thinking, and slight inattention. Memory problems are usually main problem, which can lead to the misdiagnosis of AD. Neil Patrick Harris, aka “Doogie Howser, MD”
Subacute Sclerosing Pancephalitis (SSPE) Dementia and myoclonus with onset in childhood Course usually rapid and fatal, may be aborted with antiviral drugs CSF has anti-measles antibodies, and EEG shows periodic or burst-suppression Cause probably measles or measles-like virus
Parkinson’s Disease Tremor: resting, “pill- rolling,” coarse, 3-5 Hz. Rigidity: “cogwheel” Bradykinesia or akinesia Festinating gait: small accelerating steps with decreased arm swing. Postural reflex abnormalities including a positive “pull test” Hypophonia, Micrographia Sleep Disturbances (partly iatrogenic from dopamine agonists) Cardinal FeaturesMinor Features
Huntington’s Disease Atrophy of cerebral cortex and head of caudate nuclei leads to compensatory enlargement of lateral ventricles (“bat-wing”). Excessive Cytosine-Adenine-Guanine (CAG) trinucleotide repeats (other illnesses with excessive trinucleotide repeats include: Myotonic dystrophy, Fragile X syndrome, many forms of Spinocerebellar degeneration).
Duchenne’s Type Muscular Dystrophy Sex-linked recessive inheritance with onset in early childhood Caused by loss of muscle membrane protein, dystrophin Pseudohypertophy (especially in calves) Proximal weakness: requires arms to arise from chair or floor DTRs decreased except for Achilles reflexes (ankle) Elevated muscle enzymes: CPK, aldolase
UMN vs. LMN Sign and SymptomsUpper Motor NeuronLower Motor Neuron ReflexesHyperactiveHypoactive Babinski signPositive (dorsiflexion)Negative Muscle atrophyAbsentPresent Muscle toneSpasticityFlaccidity FasciculationAbsentPresent
Amyotrophic Lateral Sclerosis Combines UMN and LMN symptoms Asymmetric limb weakness = most common presentation. Limb fatigability, twitching, wasting, and stiffness. Bulbar onset (2nd most common type) features dysarthria and dysphagia. “Lou Gehrig’s disease”
Clinical Case Scenario A patient develops progressive weakness two weeks after a viral infection. What is possible diagnosis and what tests would you order?
Guillain-Barre Symmetric weakness, usually beginning in the legs, and more marked proximally than distally. Some sensory complaints. Typical absence of deep tendon reflexes. May be marked autonomic dysfunction. Slow conduction velocity CSF shows increased protein concentration but normal cell count. Electrophysiology shows marked slowing of motor/sensory nerve conduction velocity (denervation and axonal loss)
Guillain-Barre Treatment: Plasmapheresis or IV IG
Myasthenia Gravis Insidious onset. Slowly progressive course. Diplopia, dysarthria, ptosis, extremity and generalized weakness not conforming to distribution of any single nerve. Pupillary responses not affected. Persistent activity of a muscle group leads to temporary increase of weakness > restoration of strength after brief rest.
Myasthenia Gravis Edrophonium challenge test (screening) EMG Confirmatory: Ach receptor antibody test Tx: Neostigmine, Pyridostigmine (if poor response: Corticosteroid). Consider Thymectomy in all patients < 60 yr unless only extraocular weakness.
Multiple Sclerosis Relapsing remitting symptoms Separated in space and time MRI: Multiple periventricular plaques in white matter. Oligoclonal bands in CSF.
Internuclear ophthalmoplegia When the patient attempts to look to left, left eye turns with nystagmus (abducted eye) and right eye cannot turn to left (impaired adduction). Location of lesion: Medial longitudinal fasciculus. Young adults: MS most common cause Older patients: vascular diseases.
Seizure Disorder Partial Seizures: originate in a focal region of a single hemisphere Simple Partial Seizures: no alteration of consciousness Secondary Generalization: spreads to both hemispheres Complex Partial Seizures: alteration of consciousness Brief Duration (i.e. 2-3 minutes); May have motionless staring or automatisms (involuntary motor behaviors)
Generalized seizures: involve both cerebral hemispheres from the outset (1). Tonic: sudden muscular rigidity (extension or flexion) (2) Clonic: generalized rhythmic jerking of muscles, no initial tonic phase (3) Generalized tonic clonic (may feature epileptic cry, apnea/cyanosis). Ictal activity 1-2 min; Post-ictal: incontinence, flaccidity, gradually return to normal consciousness. Disoriented, headache, sore mouth (oral trauma, muscular ache) ( 4). Atonic Seizure: brief loss of muscle tone (5). Absence ("petit mal") a few seconds of staring/blank look/unresponsive (6). Myoclonic: localized or widespread: non-rhythmic rapid jerking movements of muscles
Brown-Sequard Syndrome Contra: loss of P and T, Ipsi: loss of vib./joint position, paralysis, hyperreflexia, Babinski
Anterior Cerebral Artery Profound lower extremity weakness (contralateral) Stroke may result in paralysis/sensory loss in contralateral leg and foot.
Middle Cerebral Artery Profound upper extremity weakness (contralateral). Contralateral hemiplegia, hemisensory loss and homonymous hemianopia, eyes deviated to side of lesion. Apraxia/neglect. If left lobe involved: Global aphasia.
Posterior Cerebral Artery Contralateral homonymous hemianopia, with macular sparing. Prosopagnosia (inability to recognize faces)
Posterior inferior cerebellar artery Lateral Medullary or Wallenberg’s syndrome Sensory loss of the “FACE” 9 and 10 C.N. damage Limb ataxia Horner’s syndrome Spinothalamic sensory loss
Pure Motor Stroke Weakness of face, arm, and leg on one side of body (without cognitive, sensory, visual abnormalities) favors presence of thrombotic stroke involving penetrating arteries or small intracranial hemorrhage.
CategoryNon-fluent AphasiaFluent Aphasia Previous terms (not synonymous) Expressive, Motor, Broca’s, Anterior Receptive, Sensory, Wenicke’s, Posterior Spontaneous SpeechOutput: Sparse < 50 WPM, single words Content: Nouns and Verbs primarily, Dysarthric, Telegraphic Output: Plentiful > 100 WPM, entire phrases, Paraphasias (incorrect words, clang associations, neologisms) Response to TestsComprehension Preserved but Naming and Repeating impaired Comprehension Impaired (variable) and Naming and Repeating impaired Associated DeficitsR-sided hemiparesis (arm > leg) Minimal hemiparesis, hemianopia, hemisensory loss EtiologyCVAs, trauma, other focal lesions Focal lesions, sometimes frontotemporal dementia, AD, cerebral anoxia Location of LesionFrontal lobe, especially L MCATemporal or parietal lobe
Variants of Fluent Aphasia ConductionTranscortical (Isolation) AbnormalityCannot repeatCan only repeat (echolalia), other functions variable Nature of InjuryDisconnects arcuate fasciculus Isolates language arc from remainder of cortex EtiologyFocal lesionsAnoxia, CO poisoning, occasionally AD Location of lesionPosterior temporal lobeArea(s) surrounding peri- sylvian arc