Term
| What is the distinction between complex and simple seizures? What is the distinction between partial and complete? Primary and secondary? |
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Definition
- Complex =impairment of consciousness
- Partial = focal, complete = diffuse
- Primary = idiopathic or underlying predisposition; secondary = seizure from a focus/lesion
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Term
| What is the definition of a seizure? Epilepsy? |
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Definition
Seizure: abnormal cortical discharge that results in some clinical experience.
Epilepsy: Predisposition to recurrent, unprovoked seizures |
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Term
| How do simple partial seizures manifest clinically? Partial complex? |
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Definition
- No impairment of consciousness; depends on site of cortical discharge (e.g. occipital = blinding light, post-central gyrus = tingling, etc)
- Patient appears spacey.
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Term
| What is a secondary generalized seizure? |
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Definition
| A seizure that begins from a focus (starts with an aura, such as a tingling or funny taste), but spreads into a generalized tonic-clonic seizure. |
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Term
| How can an absence seizure be distinguished from a partial complex? |
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Definition
Absence seizure can be induced by hyperventilation, and EEG shows a 3 hertz spike and wave.
Partial complex often manifests with automatism (wringing of hands, fumbling, picking at clothing) |
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Term
| What is a common gross lesion found in patients with partial complex seizures? What are some other more general anatomic findings? |
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Definition
- Hippocampal/trmporal sclerosis, with mossy fibers sprouting in temporal lobe.
- Loss of interneurons, cortical dysplasia
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Term
| Which anatomical pathway and cellular structures are implicated in absence seizures? |
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Definition
| Thalamo-cortical circuit and calcium T channels |
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Term
| How does the hyperactive hypersynchronized discharge of seizures appear on EEG? What is the intracellular correlate of this event? |
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Definition
Interictal spike; paroxysmal depolarization shift
Represent post-burst after-hyperpolarization, due to calcium build-up opening potassium channels and GABAergic feedback inhibition |
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Term
| How do UMN lesions differ from LMN lesions in clinical presentation? |
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Definition
- LMN = fasciculations, loss of muscle bulk early, diminished reflexes, flacidity
- UMN = spasticity, increased tone in lower limb extensors, upper limb flexors, clasp-knife response, hyperreflexia, pronator drift, Babinski sign
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Term
| How is muscular force upregulated? |
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Definition
| Increased motor unit recruitment and/or increased motor unit firing |
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Term
| Distinguish fasciculations from fibrillations |
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Definition
Fasciculation = sporadic, large and long units characteristic of chronic denervating disorders (LMN lesions as well)
Fibrillation = single denervated muscle fibers, common in peripheral neuropathy, occasionally seen in dystrophy or polymyositis |
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Term
| How does muscular dystrophy present? What is the pathophysiology? |
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Definition
Gower's sign (patient cannot stand-up from prone position without assuming tent-like pose), hyperplasia of ankle (from fibrosis)
Due to mutation in the structural protein, dystrophin |
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Term
| How does polymyositis differ from dermatomyositosis? |
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Definition
- Dermato = perifasciular, vasculopathy, heliotropic rash, papules.
- Poly = endomysial infiltration, inflammation visible on MRI
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Term
| How does inclusion body myositosis differ from the other myopathies? |
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Definition
| Intracellular amyloid deposits forming vacuoles, starts distally |
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Term
| What are the EMG features of myopathy? Neuropathy? |
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Definition
- Myopathy = small, abundant, easily recrtuied motor unit potentials
- Neuropathy = Large, long, duration, poorly recruited motor unit potential with increased spontaneous activity (fasciculations)
[image]
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Term
| What are the clinical features of Guillain-Barre syndrome? |
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Definition
| Symmetrical ascending paralysis, slow nerve conduction velocities, elevated CSF protein |
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Term
| What are the EMG features of myathenia gravis? Lambert Eaton? |
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Definition
- Decreased amplitude with repetitive stimulation; "jitters" (dispersed timing of motor units)
- Increased amplitude with repetitive stimulation
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Term
| What are the histological characteristics of demyelination? |
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Definition
| Widely space myelin, segmental demyelination, "onion bulb" formation |
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Term
| What is the etiology of Charcot-Marie-Tooth and what are its clinical features? |
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Definition
| Two forms: demyelinating and axonal degenerating. Presents with pes cavus (arched foot) and hammer toes |
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Term
| What are the histological features of axonal neuropathy? |
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Definition
| Necrotizing arteritis, amyloid deposition |
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Term
| What are the cardinal signs of idiopathic Parkinson's disease? The neuropathological? |
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Definition
- Bradykinesia, cogwheel rigidity, tremor @ rest, mask facies, sign of autonomic dysfunction
- Lewy Bodies (alpha-synuclein, red with neuromelanin) in substantia nigra pars compact and locus ceruleus
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Term
| What are the clinical features of progressive supranuclear palsy? The neuropathological? |
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Definition
- Truncal rigiity, pseudobulbar palsy w/ abnormal speech, vertical gaze palsy (although Doll's eye maneuver is intact)
- Neuronal loss and gliosis; globose neurofibrillary tangles with straight (not helical) tangles
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