Neuro 4 Flashcards
Describe difference in presentation of UMN vs. LMN disorder in the face
UMN disorder = weakness of lower face with sparing of upper face
LMN disorder = weakness of upper and lower face
Describe the different levels (e.g. muscle, nerve, etc.) that can cause weakness
Muscle, NMJ, peripheral nerve, nerve root, plexus, spinal cord, cerebral hemisphere/brainstem
Describe pattern of weakness in primary muscle disorders
• Symmetric proximal muscle weakness that can affect neck muscles
Associated signs and sx in primary muscle disorder
- Muscle pain if inflammatory
* Should not cause sensory or reflex deficits
Pattern of weakness in NMJ disorder
- Wekness of proximal muscles
- Some characteristically affect extraocular and bulbar muscles
- Fluctuation in degree of weakness (may change hour to hour)
Associated signs and sx of NMJ disorder
• Should not show sensory signs or sx
Pattern of weakness in peripheral nerve disorder
- Mononeuropathy = weakness in muscles innervated by a single peripheral nerve
- Polyneuropathy = dysfunction occurs first in the muscles of the distal extremities symmetrically
Associated signs and sx of peripheral nerve disorder
• May cause numbness, tingling, or pain
What does radiculopathy mean?
• Radiculopathy = problem involving a single nerve rooth
Pattern of weakness in nerve root disorder
• Causes weakness in the muscles innervated predominantly by fibers from one nerve root
Associated signs and sx of nerve root disorder
- Radiating pain and tingling are common
* If the nerve root serves a particular muscle stretch reflex, that reflex may be depressed or absent (e.g. C5 = biceps)
Pattern of weakness in plexus disorder
• Multiple muscles in a limb are weak and do not conform to a particular nerve root or peripheral nerve pattern
Associated signs and sx in plexus disorder
• Associated sensory signs of reflex loss common
Pattern of weakness in spinal cord disorder
- Weakness in a UMN pattern below the lesion (due to interruption of the descending corticospinal tract)
- Weakness in a nerve root pattern at the level of the lesion (mimics radiculopathy)
Associated signs and sx in spinal cord disorder
- Sensory loss below lesion due to interruption of acending tracts
- Reflexes below level of lesion are increased and Babinksi usually present
- Bowel and bladder incontinence may occur
Pattern of weakness in cerebral hemisphere disorder
- Weakness of the contralateral side in an UMN pattern
- Parasagittal lesions lead primarily to leg weakness
- Lateral lesions lead primarily to face and arm weakness
- Deep lesions may lead to weakness in all 3 parts
Associated signs and sx of cerebral hemisiphere disorder
- L hemispheric lesions may cause aphasia and apraxia
- R hemispheric lesions may cause neglect or visuospatial dysfunction
- Brainstem lesions may have accompanying CN findings
Describe typical presentation of tension HA
Constant pressure in temporal and occipital region. Band-like pattern. No nausea, vomiting, or photophobia
What is a physical exam finding that remains present in brain dead patients
Deep tendon reflexes (spinal cord may still be functioning)
What part of the brain is damaged in alcohol neurotoxicity
Cerebellum (specifically the vermis = defect in truncal coordination = wide-based gait and postural instability)
Effects of thiamine deficiency in alcohols
Werknicke’s triad = confusion, ophthalmoplegia, ataxia
Approved medication used in ALS
Riluzole = glutamate inhibitor
How do you diagnose MS?
- Oligoclonal bands in CSF
- MRI brain shows periventricular hyperintense white matter lesions
Tx of MS flair
IV glucocorticoids (e.g. methylprednisolone)
What is Friedreich ataxia: imaging findings + presentation
♣ Autosomal recessive trinucleotide repeat disorder GAA
♣ Degeneration of cerebellum and spinal cord
• Ataxia, muscle weakness (usually arms > legs), loss of vibratory sense and proprioception, diabetes mellitus, hypertrophic cardiomyopathy
• Presents in childood with kyphoscoliosis
Classic presentation of CJD
Rapidly progressive dementia, myoclonus, and sharp triphasic synchronous discharges on EEG
Describe features of vestibular neuritis
♣ Acute unilateral peripheral vestibulopathy (not really inflammation)
♣ Features:
• Sudden onset single episode that can last days
• Associated with nausea and vomiting
• Severe vertigo but no hearing loss
Describe features of labyrinth concussion
Sudden onset vertigo as a result of head injury
Describe Meniere disease
♣ Increased pressure and volume of endolymph
♣ Features:
• Episodic vertigo with nausea and vomiting
• Ear fullness/pain
• Unilateral sensorineural hearing loss
• Tinnitus
Describe perilymph fistula vertigo
♣ Results from disruption of the lining of the endolymphatic system
♣ Patients hear a “pop” at the time of sudden increase in middle ear pressure (sneezing, nose-blowing, coughing, straining) followed by abrupt onset of vertigo
Describe benign paroxysmal positional vertigo (BPPV)
♣ Results from freely moving crystals of calcium carbonate within one of the semicircular canals
♣ Features:
• Brief episodes brought on by head movement
• No auditory symptoms
Describe typical sx associated with peripheral vs. central vertigo
Peripheral = tinnitus and hearing loss
Central = diplopia, dysarthria, and other sx of brainstem dysfunction
What are the signs and sx of cerebellar diseas
Dysmetria, intention tremor, dysdiadochokinesia, gait ataxia, truncal ataxia, dysarthria, nystagus
What is dysmetria
- Abnormlaity of the range of force of a movement
* Erratic, jerky movmements with over-and undershootin the target
What is dysdiadochokinesia
• Abnormality of the rate and rhythm of a movement demonstrated by asking the patient to perform a rapid alternating movement
Paraneoplastic cerebellar degeneration is usually associated with what cancers?
Gynecologic or small cell lung cancer
Diagnose: sudden onset cerebellar ataxia with associated vomiting and depressed level of arousal
Cerebellar stroke
What disease other than Marfan’s presents with a Marfanoid habitus?
Homocystinuria
Difference in presentation between Marfan syndrome and Homocystinuria
Marfan:
- Marfanoid habitus (pectus deformity, tall stature, arachnodactyly, joint hyperlaxity, skin hyperelasticity, scoliosis)
- **Normal intellect
- Aortic root dilation
- Upward lens dislocation
Homocystinuria:
- Marfanoid habitus
- **Intellectual disability
- Thrombosis (Homocysteine is prothrombotic, which may lead to premature acute coronary syndrome)
- Downward lens dislocation
- Megaloblastic anemia
- **Fair complexion
Most common infectious cause of single brain abscess
Usually direct extension from an adjacent tissue infection
Strep Viridans, Staph aureus
Describe presentation of Neurofibromatosis type 1
♣ Neurocutaneous disorder characterized by café-au-lait spots, cutaneous neurofibromas (peripheral nerve sheath tumors), optic gliomas, pheochromocytomas, Lisch nodules (pigmented iris hamartomas)
♣ Neurofibromas consist of proliferation of Schwann cells, fibroblasts, and neurites
• Appear as soft, nontender, pedunculated cutaneous lesions
Describe presentation of neurofibromatosis type 2
♣ Bilateral acoustic schwannomas, juvenile cataracts, meningiomas, and ependymomas ♣ Presentation: • Hearing loss, tinnitus, balance problems, hyperpigmented skin lesions, cataracts ♣ REMEMBER 2’s: • Chr 22 • Bilateral hearing loss • NF Type 2 • Cataracts
Presentation of acute closure glaucoma
♣ Rapid onset severe eye pain
♣ May see halos around lights
♣ Affected eye will appear injected with dilated pupil that is poorly responsive to light
♣ Can also have tearing and HA with subsequent nausea and vomiting
DIfferentiate between Cauda equina syndrome and Conus medularis syndrome
• Cauda equina syndrome
o Likely due to disc herniation or rupture, spinal stenosis, tumors, infection, hemorrhage, or iatrogenic injury
o Causes LMN signs as the nerve roots are part of the peripheral nervous system
o Usually bilateral, severe radicular pain
o Saddle hypo/anesthesia
o Asymmetric motor weakness
o Hyporeflexia/areflexia
o Late-onset bowel and bladder dysfunction
• Conus medullaris syndrome o Causes both UMN and LMN symptoms o Sudden onset severe back pain o Perianal hypo/anesthesia o Symmetric motor weakness o Hyperrreflexia o Early-onset bowel or bladder dysfunction
Describe details of paralysis in Guillan Barre vs. tick-borne
• Tick-borne paralysis
o Rapidly progressive ascending paralysis over hours to days
o Paralysis may be asymmetrical
• Guillain Barre syndrome
o Ascending symmetrical paralysis over days to weeks
Other sx besides paralysis in Guillan Barre vs. tick-borne paralysis
• Tick-borne paralysis
o Absence of fever and sensory abnormalities, and normal CSF
• Guillain Barre syndrome
o Sensation is usually normal to midly abnormal
o Autonomic dysfuction (e..g tachycardia, urinary retention, and arrhythmias) occur in 70% of patients
o CSF is usually abnormal and may show high protein with few cells
Tx of tick-borne paralysis vs Guillain Barre
Tick-borne = removal of tick resutlt in spontaneous improvement in most patients
GBS = IV Ig or plasmapharesis
Describe presentation of Essential tremor
♣ Occurs at rest and with movement
♣ Usually genetic
♣ Hands > arms > head»_space; legs
Tx of essential tremor
- Beta-blockers
- Primidone (barbiturate/anticonvulsant)
- Self-medicated with alcohol
- Benzodiasepines (clonazepam)
Treatment of trigeminal neuralgia
Carbamazepine (anticonvulsant)
