Neurology/ Neurosurgery Flashcards
Corticospinal/ corticobulbar tracts control?
Voluntary movement
Spinothalamic tract is responsible for?
Pain and temperature
Doral columns are responsible for?
Proprioception and vibration
Precentral gyrus?
Primary motor cortex
Post central gyrus?
Primary sensory cortex
Frontal lobe?
movement
executive function
personality
expressive language
Temporal lobe?
smell
hearing
memory
Parietal lobe?
sensation
visuospatial
praxias
receptive language
Occipital lobe?
vision
Cerebellum?
coordination
Brainstem components?
midbrain
pons
medulla
Where is the relay station?
Thalamus
Components of basal ganglia?
Caudate, putamen, globus pallidus, substantia niagra, subthalamic nucleus
-> motor programming
Primary motor/sensory cortex ?UMN weakness pattern ?degrees of weakness re: ACA, MCA ?sensory loss of weakness first ?cortical signs re: dominant vs. nondominant
UMN weakness - hemi pattern Varying degrees of weakness - ACA: L > F/A - MCA: F/A > L Sensory loss follows weakness Cortical signs present - Dom: aphasia - Nondom: neglect
Corona radiata
?UMN weakness pattern
?weakness/sensory loss
?cortical signs
UMN weakness - hemi pattern
Varying degrees of weakness/ sensory loss, as level above
NO cortical signs
Thalamus
?sensory loss pattern
? cortical signs
Sensory loss - hemi pattern
May have cortical signs
Internal capsule ?UMN weakness pattern ?face vs. arm vs. leg ?sensory/weakness pattern ?isolated weakness/sensory loss
UMN weakness - hemi pattern
F = A = L
Sensory loss follows similar pattern as weakness
May be isolated weakness, isolated sensory loss, or both
Spinal cord ?UMN weakness ?sensory level ?autonomic dysfunction ?brown sequard
UMN weakness usually bilateral
Look for sensory level
Autonomic dysfunction
Beware Brown Sequard
Motor neuron
?UMN/LMN
?sensory sx
?autonomic sx
UMN and/or LMN weakness
NO sensory sx
NO autonomic sx
Brainstem
?UMN
?sensory loss pattern
?CN sx
UMN weakness pattern = hemi or bilateral
Sensory loss with variable patterns - look for crossed sensory loss
CN signs/symptoms
Root
?LMN
?sensory loss
LMN weakness follows myotome pattern
Sensory loss follows dermatome pattern
Plexus
?LMN
?sensory changes
LMN weakness
Patchy sensory changes
Peripheral nerve ?LMN ?sensory ?3 patterns ?ANS sx
LMN weakness
Sensory loss
3 patterns: mononeuropathy, polyneuropathy, mononeuritis multiplex
ANS symptoms can be present
Neuromuscular junction
?weakness
?sensory sx
Fatiguable weakness
NO sensory sx
Muscle
?LMN
? sensory
LMN weakness pattern prox>distal
NO sensory sx
LOC
- alert
- confused
- delirious
- lethargic
- obtunded
- stuporous
- comatose
Lethargic
Mild decrease in consciousness, easily aroused
Obtunded
Cannot be fully aroused
Stuporous
Sleep-like state
GCS
Eyes
- 4= spontaneous
- 3= open to voice
- 2= open to pain
- 1= do not open
Voice
- 5= normal
- 4= confused
- 3= inappropriate words
- 2= incomprehensible sounds
- 1= no response
Motor
- 6= follows commands
- 5= localized pain
- 4= withdraws to pain
- 3= flexor posturing
- 2= extensor posturing
- 1= no movement
CN
I - olfactory nerve II - optic nerve III - oculomotor nerve IV - trochlear nerve V - trigeminal nerve VI - abducens nerve VII - facial nerve VIII - vestibulocochlear nerve IX - glossopharyngeal nerve X - vagus nerve XI - spinal accessory nerve XII - hypoglosseal nerve
CN I
olfactory nerve
- sensation
CN II
optic nerve
sensation - visual acuity, visual fields
reflex - pupillary light reflex (afferent = CN II, efferent = CN III)
inspection- ophthalmoscopy
CN III
oculomotor nerve
- superior rectus (elevates), inferior rectus (depresses), medial rectus (adducts), inferior oblique (elevates adducted eye, extorts abducted eye), elevator palpebral superioris (raises eyelid - lesion = ptosis)
- parasympathetic innervation to pupillary sphincter (constricts pupil) and ciliary muscles (accommodation)
Cause of ptosis?
Levator plapebrae superioris lesion (CN III)
CN IV
trochlear nerve
- superior oblique muscle (depression of adducted eye, intorsion of abducted eye)
CN V
trigeminal nerve
sensation - pain, temp, light touch of ophthalmic, maxillary and mandibular regions
motor - strength of master and temporalis, pterygoids
reflexes - corneal (afferent = CNV, efferent = CNVII); jaw jerk (afferent = CNV, efferent = CNV)
CN VI
abducens nerve
- lateral rectus muscle (abducts eye)
motor - EOM, convergence, nystagmus, saccades
CN VII
facial nerve
motor - facial movements; ask about hyperacusis (nerve to stapedius m.)
sensory - taste anterior 2/3 tongue
lesion = UMN forehead spared; LMN forehead involved
CNVIII
vestibulocochlear nerve
sensation - 512 Hz tuning fork = Weber (lateralization) and Rinne (AC vs. BC); whispered voice test
CN IX
glossopharyngeal nerve
- motor = palatal elevation
- reflex = gag (afferent = CN IX, efferent = CN X)
- sensory = taste posterior 1/3 tongue
lesion = palate deviates away from side of lesion
CN X
vagus nerve
- motor = voice quality and gag
CN XI
spinal accessory
- motor = SCM and trapezius atrophy, fasciculations, strength
CN XII
hypoglossial nerve
- motor = tongue atrophy, fasciculations, symmetry on protrusion, strength
lesion = tongue deviates toward side of lesion
Chorea
irregular, unpredictable jerky purposeless movements that flow from one body part to another
Ballismus
large-amplitude, rapid, violent, flinging movements originating from proximal muscles
Dystonia
Sustained muscle contraction causing twisting and repetitive movements or abnormal sustained postures
Tics
repetitive, rapid, irregular, patterned, stereotyped movements or vocalizations accompanied by pre-event urge
Myoclonus
Rapid, shock-like, sudden larger-amplitude involuntary movements caused by active muscle contraction (positive myoclonus) or inhibition of ongoing muscle contraction (negative myoclonus)
What does pronator drift test for?
+ if arm drops and pronates
assesses cortical weakness
Spastic vs. rigidity (hypertonic muscle tone)
spastic - velocity dependent (clasp knife)
rigidity - not velocity dependent (cog-wheel, lead pipe)
Grading scale for strength
0 = no muscle movement 1 = trace contraction/ flicker 2 = movement with gravity removed 3 = movement against gravity 4 = movement against partial resistance 5 = movement against full resistance
Deltoid (arm abduction) myotome/ nerve
C5
axillary n.
Biceps (elbow flexion) myotome/ nerve
C5/6/7
musculocutaneous n.
Triceps (elbow extension) myotome/ nerve
C6/7/8
radial n.
Extensor carpi ulnaris/ radialis (wrist extension) myotome/ nerve
C5/6/7/8
radial n
Flexor carpi ulnaris/ radialis (wrist flexion) myotome/ nerve
C6/7/8 T1
ulnar/median .
Hand intrinsic myotome/ nerve
C8/T1
ulnar n. except LOAF = median n.
Iliopsoas (hip flexion) myotome/ nerve
L1/2/3
femoral n.
Adductors (hip adduction) myotome/ nerve
L2/3/4
Obtruator n.
Gluteus maximus (hip extension) myotome/ nerve
L5, S1/2
inferior gluteal n.
Quadriceps (knee extension) myotome/ nerve
L2/3/4
femoral n.
Hamstrings (knee flexion) myotome/ nerve
L5/S1/2
sciatic n.
Gastrocnemius (plantar flex ankle) myotome/ nerve
S1/2
tibial n.
Tibialis anterior (dorsi flex ankle) myotome/ nerve
L4/5
deep peroneal n.
Grading reflexes
deep tendon 0 = no response 1+ = requires reinforcement (Jendrassik maneuver) 2+ = normal 3+ = associated with spread of reflex 4+ = associated with clonus
cutaneous - abdominal -> above umbilicus (T8/9/10), below umbilicus (T10/11/12) - plantar reflex (L5, S1/2) other - primitive reflexes (grasp, root, etc) - Hoffman
Deep tendon reflexes segmental level and peripheral nerve
Bicep = C5/6, musculocutaneous n. Tricep = C7/8, radial n. Brachioradialis = C5/6, radial n. Knee jerk = L2/3/4, femoral n. Ankle jerk = S1/2, sciatic n.
Levels of principle dermatomes
C5 = clavical C6 = thumb C7 = middle finger C8 = ring and little finger T4 = nipples T10 = umbillicus T12 = suprapubic L1 = inguinal area L2 = knee L4 = medial side first toe L5 = dorsum of foot S1 = lateral foot
How do you test for dysdiadochokinesia?
Rapid alternating movements
How to test for dysmetria?
Point to point movement
What gait will you see ataxia?
Tandem gait
How do you bring out gastrocnemius muscle weakness (S1)?
Walk on tip toes
How do you bring out anterior tibialis weakness (L5)?
Walk on heels
Rhomberg tests integration of what?
Visual, vestibular and proprioceptive function
- remove visual pathway when close eyes (balance if proprioception and vestibular pathways intact)
How many levels does the nervous system have?
10
UMN/CNS (level 1-6)
- Cortical - hemiplegia/ hemianesthsia + cortical findings (aphasia, neglect, apraxia), seizures, loss of consciousness
- Subcortical - hemiplegia/ hemianesthsia, visual field cut, no cortical findings
- Basal ganglia - rigidity, involuntary movement, no sensory sx
- Cerebellum - ataxia, no sensory sx
- Brainstem - CN findings with (often contralateral) motor and sensory findings, loss of consciousness
- Spinal cord - sensory level, bowel and bladder sx
LMN/PNS (level 7-10)
- Motor neuron weakness, atrophy, fasciculations, no sensory sx
- Root/plexus/nerves - variable motor/sensory sx, areflexia
- Neuromusclar junction - fatiguability, diplopia, ptosis, dysphagia, no sensory sx
- Muscle - proximal weakness, no sensory sx
UMN lesion
UMN
- forehead sparing, CN reflexes absent, hyperactive jaw reflex
- normal bulk
- increased tone
- distal weaker than proximal strength; arm extensors weaker than flexors, leg flexors weaker than extensors
- increased reflexes, plantar upping, +ve Hoffman
LMN lesion
- forehead involving facial droop, fasciculations of tongue
- decreased bulk
- decreased tone
- pattern of strength re: localization of lesion
- reflexes decreased, plantar downgoing
Sensory patterns re: lesions
Hemianesthesia (all one side of body) = cortical or subcortical Ipsilateral face contralateral body loss of pain and temperature = brainstem Sensory level (bilateral below certain level) loss of pain, temp, vibration, proprioception) = spinal cord Stocking glove pattern = polyneuropathy Loss of sensation in distribution innervated by affected nerve = CN/ peripheral nerve/ plexus
Weakness
Loss of power/strength
- partial = paresis
- full = paralysis
- > corticospinal tract
ddx re: 10 levels of NS
How does anterior horn cell weakness present?
Progressive dysphagia and dysarthria with both UMN and LMN signs
- no sensory and no bowel/ bladder sx
Weakness muscle workup
Sx - proximal muscle weakness +/- muscle pain, no sensory sx
Inv
- ESR, CRP, muscle enzymes, EMG/NCS, muscle biopsy
Ddx/tx
- Myositis -> immunosuppression
- Myopathy -> correct metabolic derangement
- Rabdo -> supportive hydration +/- dyalysis
- Muscular dystrophy -> nil
Weakness NMJ workup
Sx - fatiguable weakness in small muscles causing ptosis, diploplia, dysphagia, dysarthria, progressing to proximal > distal weakness and no sensory sx
Inv - EMG/ NCS, repetitive stimulation, single fiber EMG, Tension test, ice pack test, anti-Ach receptor antibodies, CXR/CT chest (r/o thymoma for MG)
Ddx/tx
- Myasthenia gravis -> ABC, admit and monitor resp status, swelling assessment, steroids, IVIG or plasmapheresis, Mestinon, PT/OT
- Lambert-Eton syndrome -> steroids, IVIG, plasmapheresis, chemotherapy (if cancer), Mestinon, Amigampridine
- Botulism toxin -> anti-toxin if early, otherwise botulism immunoglobulin and supportive tx
Weakness peripheral nerve workup
Sx - variable distribution based mononeuropathy (focal weakness) vs. polyneuritis (symmetric distal > proximal weakness)
Inv - EMG/NCS, LP, medication review, social history, FBS, TSH, Vit B12, LFT, Cr, BUN, infectious, vasculitic, nutritional workup pro
MRI L spine if presumed cause equina
Ddx/tx
- AIDP = GBS -> ABC, admit and monitor resp status, plasmapheresis or IVIG, PT/OT
- CIDP -> corticosteroids, plasmapheresis of IVIG
- Medication/drug induced
- DM -> glycemic control
- Thyroid -> correct
- Vit B12 deficiency -> B12
- Vasculitis -> immunosuppression
- Infections (Lyme, diphtheria) -> tx re: infection
- Trauma -> surgery, rehab
- Cauda equina secondary compression -> urgent neurosurgery/ radiation (tumor)
Weakness plexus workup
Sx - weakness involving multiple myotomes/ dermatomes and peripheral nerve distributions
Inv - MRI plexus, EMG/NCS, FBS
Ddx/tx
- Bracial neuritis -> supportive
- Trauma -> supportive
- DM -> glycemic control
Weakness root workup
Sx - weakness affecting specific myotome with sensory sx distributed along same dermatome, often with neck/ back pain with neuropathic radiation along dermatome
Inv - x-ray/ CT/ MRI spine, EMG/NCS
Ddx/tx - Herniated disc - OA/ degenerative disc disease - Avulsion - Tumor tx - supportive, PT/OT, consult NSx/ortho
Weakness anterior horn cell workup
Sx - classic diseases causing progressive dysphagia, dysarthria, with UMN and LMN signs, no sensory sx, no bladder/ bowel sx
Inv - El Escorial criteria
- r/o other possible localizations/ disorders
Ddx/tx
- Amyotrophic lateral sclerosis
- Primary lateral sclerosis
- Primary muscular atrophy
- Progressive bulbar palsy
- Pseudobulbar palsy
- > supportive tx
Weakness spinal cord workup
Sx - para or quadra-plegia/ paresis with sensory level, bowel and bladder sx +/- back pain
Inv - MRI + gadolinium of spinal cord; LP (cell count, cytology, flow cytometry, infx)
Infx workup - syphilis, CMV, HTLV, mycoplasma, HSV, VZV, HIV, etc.
Paraneoplastic antibodies
Ddx/tx
- Trauma -> consult NSx
- MS -> steroids +/- disease modifying tx
- Transverse myelitis -> steroids
- Neoplasms/ metastasis -> consult NSx, med/rad onc
- Vascular -> optimize risk factors
Weakness brainstem workup
Sx - hemiplegia/ paresis associated with CN findings (+/- asymmetric/ symmetric bilateral weakness)
Inv - MRI brain, other inv. re: results MRI
Ddx/tx
- Stroke (ischemic/ hemorrhagic) -> stroke tx
- Vascular (AVM, aneurysm, etc) -> consult NSx
- Mass lesion - consult NSx/ oncology
- Infection (abscess) - abx, antifungal, antiparasitic; consult ID
- MS -> steroids +/- disease modifying tx
Weakness subcortical workup
Sx - hemiplegia/paresis involving face, arm and leg equally +/- visual sx, sensory sx, etc.
Inv - CT/MRI brain, inv. re: findings
Ddx/tx
- Stroke (ischemic/hemorrhagic) -> stroke tx
- Vascular (AVM, aneurysm, etc) -> consult NSx
- Mass lesion - consult NSx/ oncology
- Infection (abscess) - abx, antifungal, antiparasitic; consult ID
- MS -> steroids +/- disease modifying tx
- Trauma (contusion) -> consult NSx/ supportive
Weakness cortical workup
Sx - hemiplegia/paresis
ACA - mostly leg
MCA - face and arm >leg
+ cortical sx (aphasia if dominant hemisphere; apraxia and neglect if non dominant hemisphere)
Inv - CT/MRI brain; inv. re: imaging
Ddx/tx
- Stroke (ischemic/hemorrhagic) -> stroke tx
- Vascular (AVM, aneurysm, etc) -> consult NSx
- Mass lesion - consult NSx/ oncology
- Infection (abscess) - abx, antifungal, antiparasitic; consult ID
- MS -> steroids +/- disease modifying tx
- Trauma (contusion, SDH, etc.) -> consult NSx/ supportive
- Other causes with no imaging findings (Todd paralysis, hemispheric migraine, hypoglycaemia) -> tx re: cause
Stroke
Ischemic - thrombic vs. embolic
vs.
Hemorrhagic - ICH vs. SAH
Time for tPA
less than 4.5h from sx onset
RF hemorrhagic stroke
HTN smoking increased age FHx atherosclerosis bleeding disorder increased EtOH cocaine, amphetamines trauma vasculitis aneurysm AVM tumor amyloid angiopathy
RF ischemic stroke
increased age smoking DM hyperlipidemia HTN Afib prev. stroke/ TIA FHx cardiac source atherosclerosis obesity/ physical inactivity OCP/HRT OSA elevated homocysteine ethnicity hypercoaguable state hypo perfusion
CNS vascular anatomy
ACA = contralateral leg> face/arm involvement
MCA = contralateral face/arm >leg involvement
- dominant = aphasia
- nondominant = apraxia, neglect
PCA = contralateral vision
Basilar = variable sx involving weakness, CN (diplopia, dysphagia, dysarthria) and cerebellar (ataxia) sx
Oslar nodes, Janeway lesions, Roth spots, splinter hemorrgahes, petechia are signs of what?
Endocarditis
Stroke investigations
Dx and type of stroke
- Noncontrast CT head - hemorrhagic vs. ischemic
- LP - suspicious SAH and CT negative (RBC, xanthochromia)
- MRI - type and localization (esp. acute ischemic infarcts, posterior fossa strokes)
Etiology stroke
- carotid doppler US (carotid stenosis)
- CT angiography (atherosclerosis, dissection, aneurysms, intracranial vascular lesions)
- MRI angiography (AVMs, aneurysms, carotid)
- conventional angiography - gold standard for AVMs and aneurysms (invasive)
- TTE (cardiac emboli)
- TEE (atrial thrombi, atheromatous aortic disease, valve disease, PFO)
- holder
- hyper coagulable work up
Stroke factors/ secondary prevention
- fasting blood glucose
- fasting lipids
- BP
- smoking/ EtOH/ drugs
- CBC, INR, PTT, bytes, Cr, BUN
- LFT, CK (prior to statins)
BP target stroke
<220/120 in pt without tPA
<180/105 in pt with tPA
Stroke management
- tPA if indicated (<4.5hr, no CI)
- BP (<220/120, <180/105)
- ASA 160mg chewed or 650mg PR
- rehab (SLP, OT, PT)
secondary prevention - anti platelet (ASA, placid, Aggrenox)
- DM tight glycemic control
- lipids (statins)
- BP (ACEI/ARB or diuretic -> <140/90; if DM <130/80)
- lifestyle
- Surgery (endarterectomy/ stunting)
complication prevention - DVT prophylaxis
- Mobilization/ positioning re: pressure ulcers
- swallowing screen/ diet appropriate
Hemorrhagic stroke tx
ICH - ABC, reverse coagulation, supportive, NSx consult, ICP management
SAH - ABC, reverse coagulation, aggressive BP control (SBP <160), urgent angiographic imaging, SAH precautions, nimodipine, NSx consult, definitive management of underlying cause
ICP management
- HOB >30 (increase venous outflow)
- neutral neck - avoid neck compression
- avoid hypotension
- normal to mild hypercarbia (only hyperventilate if signs of herniation or as bridge to surgery)
- sedation (opioids, versed, propofol)
- intracranial pressure monitoring (external ventricular drain, intraparenchymal monitor)
- osmotic (mannitol, hypertonic saline)
- paralytics
- surgical options (clot evacuation, decompressive craniotomy)
CI tPA
absolute
- intracranial hemorrhage
- severe uncontrolled HTN
- head trauma/stroke last 3mo
- thrombocytopenia/ coagulopathy
- therapeutic anticoagulation (LMWH last 24h)
relative
- age >75-80
- improving stroke sx
- coma/severe stroke (higher risk hemorrhagic transformation)
- recent major surgery
- recent gi/gu bleed (within 3wk)
- seizures
- recent MI
- CNS structural lesions (neoplasm, AVM, aneurysm)
Positive sensory complaints
paresthesia/dysesthesia = tingling, pins and needles, burning, neuropathic pain
Negative sensory complaints
hypoesthesia/anesthesia = numbness, diminution/ absence of feeling
Which tracts essential for sensory lesions?
Spinothalamic and dorsal column pathways
Sensory cortical/subcortical and brainstem - ddx and workup
Ddx
- vascular (CVA, ICH, SAH)
- inflammatory (MS)
- neoplasm
- infection
Inv - CT head, MRI brain (brainstem suspected)
+/- LP
Tx - underlying cause
Sensory spinal cord - ddx and workup
Ddx
- vascular (cord infarction)
- neoplasm
- inflammatory (MS)
- infection (syphilis)
- nutritional (B12 deficiency)
- trauma
- syringomyelia
- paraneoplastic
Inv - MRI cord +/- LP
- serology, vit B12, paraneoplastic antibodies
tx
- optimize vascular rf
- consult NSx/ rad onc if mass
- steroids for inflammation
- ABx for infection
- replace deficiencies
- steroids/PLEX and rx underlying cancer if paraneoplastic
Sensory polyneuropathy ddx and workup
Ddx
- metabolic (DM, uraemia)
- drug (chemo, EtOH)
- infection (HIV, Lyme)
- paraneoplastic
- inflammatory (amyloid, sarcoid, vasculitis)
- heritable
- idiopathic
Inv - EMG/NCS
- FBS, Cr, BUN, TSH, AST, ALT, serology re: infection, CD4 count, inflammatory workup (ESR, CRP), paraneoplastic antibodies
Tx
- optimize DM, kidney function, liver function
- d/c drug if cause
- Rx infection
- steroids/PLEX and rx underlying cancer if paraneoplastic
- steroids, etc for inflammatory causes
Sensory mononeuropathy ddx and workup
Ddx
- stretch
- compression (CTS)
- contusion
- laceration
note: peripheral nerve injury often occurs as part of more extensive injury and tend to go unrecognized
Inv - EMG/NCS
+/- imaging
FBS, Cr, BUN, TSH, AST, ALT, serology re: infection, CD4, inflammatory workup (ESR, CRP), paraneoplastic antibodies
Tx
- task modification, splints, PT/OT, ergonomics
- severe/axonal loss on EMG/NCS consider surgical release
- consult plastic surgery re: nerve injuries
Neuropathic pain
Pain from dysfunctional/disruption of either central or peripheral nervous system
- allodynia (painful response to non-painful stimulus), hyperalgesia (increase pain in response to painful stimulus), constant pain (burning, sharp, stabbing, shooting, electrical)
- worse at rest, constant pain
Somatic vs. visceral nociceptive pain (tissue damage)
Somatic = well localized, sharp, short lasting
Visceral = originates from organ/cavity lining; poorly localized, crampy, diffuse
Neuropathic pain ddx
Abnormal neural activity
Sympathetic - CRPS
Central (abnormal CNS activity) - phantom limb, post-stroke, post-spinal injury, MS pain
Peripheral (nerve damage/pressure) - post herpetic neuralgia, trigeminal neuralgia, diabetic neuropathy, nerve entrapment, HIV sensory neuropathy
Seddon categories of peripheral nerve injuries
Neuraprazia
- focal demyelination
- temporary conduction block/ paralysis
- complete recovery typical
Axonotmesis
- axonal destruction with preservation of myelin
- prolonged conduction block/ paralysis
- recovering axon can follow intact myelin base to reestablish connectivity
- complete recover possible
Neurotmesis
- complete transection
- prolonged/ permanent conduction block/ paralysis
- loss of myelin base to guide axon
- neuroma formation results
- unlikely to have complete recovery without surgery
Complex regional pain syndrome (CRPS)
chronic neuropathic pain developing over months which affects an extremity and cannot be localized to a peripheral nerve or root territory
- all tissue types in vicinity affected (deem, thickened skin, muscle wasting, patchy demineralized bone)
- severe/permanent changes within 1yr
type 1 = no definable lesion/insult
type 2 = definable lesion/insult (e.g. trauma, head injury, stroke, infection, idiopathic, MI, etc)
regional sympathetic nerve block can be diagnostic and therapeutic
Dysarthria
abnormality of speech
- articulation problem re: lesion in motor pathways controlling speech
- any speech subsystems can be affected (respiration, phonation, resonance, prosody, articulation)
- often with oropharyngeal dysphagia
Aphasia
abnormality of language
- lesion in dominant hemisphere
- paraphasic errors (mispronunciation or inappropriate substituted words), including semantic (based on meaning) or phonemic (based on sounds) errors and neologisms (creation of new words)
Brocas area
motor patterns - fluency
Wernicke’s area
autitory centre - comprehension
Articulation re: CN
mama = CN VII gaga/caca = CN IX, X lala = CN XII
Global aphasia sx
fluency
naming
comprehension
repetition
Brocas aphasia sx
fluency
naming
repetition
Wernickes aphasia sx
naming
comprehension
repetition
Conduction aphasia sx
naming
repetition
Transcortical motor aphasia sx
fluency
naming
Transcortical sensory aphasia sx
naming
comprehension
Transcortical mixed aphasia sx
fluency
naming
comprehension
Timeline of ddx aphasia
sec-min = vascular hr-d = infection d= inflammation wk-mo = neoplasn mo-yr = degenerative
Aphasia investigation
neuroimaging - Cat or MRI brain +/- LP, EEG, etc
Aphasia management
Underlying etiology tx
supportive care - modified diet, SLP
Dysarthria based on localization - workup, tx cerebral cortex basal ganglion (hypophonation) cerebellum (scanning speech) brainstem (brainstem findings)
inv - neuroimaging (CT head, MRI brain)
+/- LP, serum tests
Tx re: cause
Dysarthria based on localization - workup, tx isolated CN palsies - CN VII - CN IX/X (structural) - CN CII (structural)
Inv - MRI brain, EMG/NCS
Tx re: cause
Dysarthria based on localization - workup, tx
Motor neuron
(spastic/ hyper nasal), degenerative
Inv - diagnostic criteria and r/o other cause
Supportive care
Dysarthria based on localization - workup, tx
NMJ (fatiguable) - MG
Tensilon/ice pack test, Anti-AchR antibody, etc.
- NCS with repetitive stimulation
- Single fiber EMG
MG management
Dysarthria based on localization - workup, tx
Muscle - inflammatory, metabolic, drug/toxin induced, genetic
Inv - EMG/NCS, CK, etc
Supportive care and tx curable cause
Dysarthria based on localization - workup, tx
larynx/respiratory (hypo phonic)- structural
Inv - laryngoscopy, CXR, PFT, etc.
consult ENT/pulmonary prn
Location of disease in movement disorders?
basal ganglia and/or cerebellum
Hyperkinetic movement disorder
abnormal movement disorders
- dystonia, chorea, myoclonus, ballismus, tremor, tics
Hypokinetic movement disorder
lack/paucity of normal movement disorders
- Parkinsonism
Tremor
rhythmic oscillation of a body part secondary to alternating or synchronous contraction of reciprocally innervated antagonistic muscles
Classification of tremors
- based on when it is most prominent
Rest - patient quietly resting (Parkinson disease)
Action - during voluntary muscle movement (cerebellar disease, MS)
Postural - patient maintaining a posture against gravity (enhanced physiologic tremor, essential tremor)
Parkinsonism
syndrome characterized by tremor (predominantly rest tremor), rigidity, bradykinesia, postural instability, classic gait
classic gait - decreased initiation, bradykinetic, shuffling, stooped posture, decreased arm swing, destinations, en bloc turning
Parkinsonism does not equal Parkinson disease
Red flags re: Parkinsonism
symmetric symptoms
early postural instability or falls
impaired up gaze
poor response to Sinemet (carbidopa- levodopa)
Treatment hyperkinetic movement disorders
trial propranolol
lifestyle (less caffeine, EtOH)
Neurologist referral
Treatment hyperkinetic movement disorders
Parkinson disease = trial L-dopa
neurologist referral if red flags
Wilson disease
- autosomal recessive disease of copper metabolism
- mutation in ATP7B on chrm 13 -> encodes Cu transporting ATPase in liver -> Cu not incorporated into ceruloplasm to excrete in bile -> Cu accumulation in liver, brain, and other tissues
sx - liver cirrhosis -> failure
- dysarthria, dystonia, asymmetrical tremor
- arthropathy, osteopenia
- hemolytic anemia
- Fanconi syndrome, urolithiasis, hematuria
Kayser-Fleischer rings in eyes
Inv - serum ceruloplasmin, 24h urine for supper, slit lamp exam, neuroimaging, liver biopsy
tx - diet modifications, chelation (e.g. zinc)
Gait
manner of walking
- coordination of vision, vestibular function, cerebellar function, sensory perception, and motor capabilities
Ataxia
impaired ability to coordinate muscular movements (axial and/or appendicular muscles involved)
Ddx gait dysfunction
Vision - cataracts, glaucoma, macular degeneration, etc.
- ophthalmology consult
Vestibular system (vertigo, n/v, nystagmus) -> central vs. peripheral - vascular, tumor, abscess, BPPV, labyrinthitis, etc.
- MRI, Dix-Hallpike, Fukuda stepping test, etc
- Neuro referral; Epley; symptomatic tx, etc.
Cerebellar system (ataxia) - structural, toxins, inborn error of metabolism, degenerative
- MRI, EtOH hx, tox screen, Vit E, Vit B12, genetics
- neuro referral, PT/OT
Motor system (weakness) - UMN, LMN - weakness/movement disorder workup/tx
Sensory system (decreased proprioception/ joint position +/- pain and temperature; positive Rhomberg) - cortical, subcortical, brainstem, spinal cord (posterior columns), radiculopathy, polyneuropathy, etc - sensory workup/tx
Headache
pain anywhere in the head or neck
- > brain has NO nociceptors so does not feel pain
- > dura mater has nociceptors
Headache red flags
- first/different
- worst
- thunderclap hx/acute
- persistent
- > 50yo
- worse in recumbency/ with Valsalva
- worse in AM
- hx trauma, cancer
- abnormality on neuro exam
- fever
- meningismus
- papilledema, retinal hemorrhage
- severe HTN
- hypercoaguable state/ bleeding disorder
- taking anticoagulants
- pregnancy
- CO exposure
- jaw claudication/scalp tenderness/ tenderness over TA/ PMR/ monocular blurred vision
- cocaine/amphetamine use
Secondary causes of headache - ddx, workup, management
SAH
- thunderclap onset
- CT: acute blood in subarachnoid space
- LP: high RBC + xanthochromia
- refer NSx
Temporal arteritis
- > 50yo, monocular blurred vision, tender over temporal artery, jaw claudication, scalp tenderness, PMR
- increased ESR, temporal artery biopsy
- high-dose corticosteroid
Venous thrombosis
- diffuse h/a, hx clots, OCP/HRT, hyper coagulable state, low flow state, dehydration, sepsis
- MRV: thrombsis +/- venous infarcts
- abnormal hyper coagulable workup (INR/PTT/Pro C/ Pro S/ ATT etc)
- anticoagulate
Intracranial hematoma
- hx trauma, bleeding disorder
- acute = rapidly progressive neurologic deficits
- chronic = h/a may be only sx
- CT: EDH, SDH, ICH, IVH
- refer NSx
Severe arterial HTN
- HTN, encephalopathic, papilledema, Hx cocaine, amphetamine, MAOI
- positive drug screen, urine metanephrines
+/- CT head
- treat HTN; manage underlying condition
Idiopathic intracranial HTN (pseudotumor cerebri)
- worse in AM/ recumbent. Valsalva, papilledema, worsening VA/VF
- CT = no mass; LP = high opening pressure
- Diamox, Topamax, Lasix
- Ophth/NSx consults
Intracranial infection
- febrile, septic, meningismus, rash, encephalopathic, decreased LOC
- LP (check opening pressure)
- bacterial = increased protein, decreased glucose, increased WBC
- viral = increased protein, n glucose, increased WBC (lymphocytes)
tx- antibiotics/ antivirals
Mass lesion (abscess, tumor, etc.)
- gradually progressive h/a with focal neurologic findings
- CT - ring enhancing lesion
- NSx referral
Primary headache ddx
Migraine
- aura, mod-severe throbbing, worse with activity, n/v, photophobia, phonophobia
- NSAIDs, triptans, DHE
- prophylactic = propranolol, TCAs, AEDs
Tension
- later in day, no associated sx, mild-mod dull, aching, band-like
- NSAIDs, tylenol
- prophylactic = TCAs, AEDs
Cluster
- M>F, severe stabbing unilateral/ periorbital pain with ipsilateral autonomic signs (tearing, miosis, hydrous, conjunctival injection), seasonal recurrence of multiple episodes with intermittent remission
- tx O2, triptans, DHE
- prophylactic = steroids (short term), verapamil, methysergide, lithium
Medication overuse
- worsening chronic h/a >15d/mo of OTC analgesia and >10d/mo triptans, ergots, combination analgesia
- drug holiday
Transient loss of consciousness (TLOC)
transient loss of awareness and/or responsiveness caused by various mechanisms
Syncope
TLOC caused by reduced blood flow and O2 and glucose to the brain
Seizure
paroxysmal, abnormal and synchronous discharge of cortical neutrons, resulting in various semiologies
Epilepsy
chronic condition characterized by >2 unprovoked seizures
Inhibitory and excitatory neurotransmitters in seizures
inhibitory = GABA (decreased in seizures) excitatory = glutamate (increased in seizures)
Ddx syncope
Hypovolemia
Hypotensive - vasovagal, drugs, dysautonomia
Cardiac - arrhythmia, contractility issue, inflow/ outflow obstruction
Metabolic - hypoglycaemia, anemia
Cerebrovascular - vertebrovascular disease, vasospasm
Multifactorial
Ddx seizure
Focal vs. generalized
focal (activation localized area within one hemisphere)
- simple (focal without impairment of consciousness)
- complex (focal with impaired consciousness)
generalized (activation bilateral cerebral hemisphere; always associated with LOC; focal sx may evolve to bilateral convulsive sx)
- convulsive = tonic, clonic, tonic-clonic, atonic, myoclonic
- non-convulsive = typical absence, atypical absence
Status epilepticus
- life threatening condition
- one continuous seizure or recurrent seizures without regaining consciousness between seizures
- > 30min
management: - O2, IV
- thiamine and dextrose
- IV lorazepam 0.1mg/kg
- IV phenytoin (incompatible with glucose-containing solutions)
-30-50min if seizure persisting intubate and IV phenobarbital or propofol infusion (burst suppression on EEG) - urgent EEG if necessary
Convulsive seizure
episode of abnormal muscle contraction, usually bilateral
Myoclonic seizure
sudden, brief (<100ms), involuntary contractions of muscles
Clonic seizure
prolonged, regular, repetitive movement, involving same muscle group, 2-3Hz
Tonic seizure
sustained muscle contraction lasting seconds to minutes
Tonic-clonic seizure
tonic phase followed by clonic phase
Atonic seizure
sudden loss of muscle tone lasting approx 1-2sec
Typical absence seizure
brief (sec) loss of consciousness without convulsions, with generalized 3Hz smile and slow waves on EEG
Atypical absence seizure
brief LOC without convulsions, abnormality of tone, 2Hz spike and slow waves on EEG
Seizure investigations
CBC, lytes, Ca, Mg, Cr, BUN, liver enzymes, TSH
- LP if suspicious of infection
- CT/MRI
- EEG
-> provoked vs. unprovoked
Seizure management
Antiepileptic drugs
- affect voltage gate Na channels, GABA metabolism, Ca currents
Valproate - increases GABA
- generalized or partial/focal seizures
Carbamazepine - Na channel antagonist
- partial/focal onset seizures
Lamotrigine - Na channel antagonist, decreases glutamate
- generalized and focal seizures
Topiramate - Na/Ca channel modulation causing decreased glutamate
- generalized and focal seizures
Dilantin - Na channel antagonist
- generalized and focal seizures
Mental status
Attention and arousal, as well as cognition and executive function
Altered mental status ddx
True altered mental status - dementia or delirium
Mimic - depression, mania, psychosis, conversion, malingering
Delirium
acute change from baseline in attention and arousal and one or more cognitive domain that fluctuates
- organic cause
Coma
pathologic state of unarousable unconsciousness (symptom not diagnosis)
Ddx coma
- locked-in syndrome - pt paralyzed but alert and aware
- akinetic mutism - pt lacks impulse to move
- malingering
- persistent vegetative state (pt barely emerged from coma or progressed to profound dementia)
- brain death
Coma
Focal - neurologic, bilateral hemisphere or brainstem (hemorhagge, infarction, neoplasm, abscess, trauma, herniation)
Diffuse - systemic deficiencies- hypoexmia, hypercarbia, etc.;
excesses - ureic, hepatic encephalitis, metabolic acidosis, DKA, thyroid storm, etc.
Coma Workup
ABC, IV, O2, monitors, STAT investigations
- thiamine, glucose and/or Narcan
Neuro exam - CN, motor tone, deep tendon reflexes, plantar reflex
Inv - CT/MRI
- ABG, CBC-D, bytes, Ca, Mg, Cr, BUN, urinalysis, ALT, AST, PTT, INR, NH3, albumin, TSH, etc.
Herniation tx - mannitol, HOB >30, normocarbia/ normothermic, NSx consult
Treat underlying causes
Concussion (mild traumatic brain injury)
immediate and transient loss of consciousness without macroscopic structural damage
Categorization head injury severity
- mild = GCS 13-15 with brief LOC or impaired cognition
- moderate = GCS 9-12 or LOC >5min
- severe = GCS 3-8
CPP equation
CPP = MAP - ICP
normal CPP >50mmHg
normal ICP <20mmHg
Signs of herniation
posturing, dilated and unreactive pupil
What CN palsy is common with increased ICP?
CNVI
Workup head trauma
trauma blood workup
CXR, lateral c-spine xr +/- pelvic xr
CT head if GCS <13 and re: CT head rules
Canadian CT Head Rule
- adults with minor head injury who are not anticoagulated
Order CT head if
high risk - GCS <15 at 2hr post-injury; suspected open or depressed skull #; sign basal skull #; vomiting x2; age >65
medium risk - amnesia for events 30min before; dangerous mechanism (pedestrian struck, ejection MVC, fall 3ft/ 5stairs)
Epidural hematoma
Hyperdense biconvex extra axial collection on CT
- no crossing suture lines
- often arterial (middle meningeal artery)
- LOC then lucid interval
- NSx
Subdural hematoma
Crescentic hyper dense extra axial collection crossing suture lines, often along supratentorial convexity
- subacute >4d old = isodense
- chronic >2wk old = hypodense
- often venous (bridging veins)
- uncal herniation (ipsilateral fixed and dilated pupil, contralateral hemiparesis, declining LOC)
- NSx
Intraparenchymal hemorrhage/ contusion
patchy, ill-defined hyper density within brain parenchyma within edematous background; often in anterioinferior frontal or temporal lobes
- NSx
Traumatic subarachnoid hemorrhage
- hyper dense blood layer in sulci often adjacent to contusions or extra axial hemorrhages
- asymmetric (vs. aneurysmal SAH)
- NSx
Skull fracture
- irregular hypodense lines that are thin without branching (vs. vessels) and not along known sutures (coronal, sagittal)
- bone windowed CT
- NSx
Brain death
irreversible loss of function of brain, including brainstem
Brian death criteria
Prerequisites
- evidence (clinical or neuroimaging) of acute CNS catastrophe compatible with brain death
- no complicating factors
- no intoxications or poisonings (time of drugs to leave system)
- normothermic
Requirements
- coma or unresponsive - no cerebral motor response to pain in ANY extremities (beware spinal reflex)
- no brainstem reflexes - pupils fixed and dilated; ocular movements (no oculocephalic or vestibuloocular reflexes); no facial movements/reflexes; no pharyngeal movements (gag, cough); positive apnea test (no resp effort with ventilator off and increase PaCO2 >60mmHg or 20 above baseline; as long as PO2 >200mmHgm SB >90mmHg, normothermic and euvolemic)
Confirmatory investigations
- conventional (catheter) angiography
- EEG
- trancranial US
- technetium-99m hexameethylpropylene amine oxide brain scan
- somatosensory evoked potential
Organ donation
- brain death or donation after cardiac death
absolute CI
- age >80yr
- HIV infection (relative CI HBV, HCV)
- active metastatic cancer
- prolonged hypotension or hypothermia
- DIC
- sickle cel anemia or hemoglobinopathy
note: sepsis not CI
