Neurology Course Flashcards
Gerstmann syndrome 4 symptoms
Acalculia, agraphia, L-R disorientation, finger agnosia
Foster-Kennedy Syndrome
Large meningioma compressing the olfactory bulb with raised ICP from frontal lobe
Pathway from cortex to peripheral nerves
Cortez, internal capsule, thalamus, basal ganglia, brain stem, spinal cord, peripheral nerve
Temporal lobe localising signs
Auditory cortex, receptive dysphasia, memory loss, upper quadrantanopia
Antons syndrome
Cortical blindness with bilateral occipital lobe lesions. Confabulation with blindness.
Single Basilar artery blood supply
Non-fluent aphasia
Brocas, transcorticol motor, usually frustrated, cominant frontal lobe
Fluent aphasia
Wernickes, transcorticol sensory. Unable to comprehent, not frustrated, dominant temporal lobe
Conduction aphasia
Mix between the 2, able to comprehend with elements of fluent aphasia - poor repetition. Arcuate fasciculus
Pathway of motor neurons
Cerebral cortex, corona radiata, internal capsule, crus cerebri, corticospinal tranct. Crosses in the lower medulla.
Blood supply of Internal capsule
Lenticulate arteries off of the penetrating branches of MCA
Blood supply and purpose Thalamus
Terminal for all sensory neurons, PCA is blood supply
Thalamus rule of 4s
Anterior - language and memory, lateral - motor and sensory function, medial (brain stem) arousal and memory, posterior involved with visual function
Spinothalamic tract
Pain, temperature, sensory tract to primary sensory cortex. Decussate immediately in spinal cord.
Dorsal collum
Proprioception, decussate in the medial lemniscus in the lower medulla.
Language differentiator of cortical involvement
Aphasia is always cortical - dysarthria can be lower or cortical
Internal capsule stroke pattern
Pure motor stroke
Differentiators cortical to sub-cortical
Neglect, inattention, language are all CORTICAL
Three regions of the cerebellum
2 hemispheres and vermis: everything in the cerebellum decussates twice. Left causes left, right causes right
Vermis lesion symptoms
Truncal ataxia, nustagmus - classic is with alcohol.
Brainstem rules of 4
4 cranial nerves in the medulla, 4 in the pons, 4 above the pons.
4 structures in the midline beginning with M
4 structures to the side beginning with S
4 motor nuclei that are in the midline are those that divide equally into 12 (3,4,6,12)
4 medial structure int he brainstem
Motor pathway, medial lemniscus, medial longitudinal fasciculus, motor nucleus
4 side structures are
Spinocerebellar pathway, spinothalamic pathway, sensory nucleus of the 5th CN, sympathetic tract
Cranial nerves
Olfactory, Optic, Oculomotor, trochlear, trigeminal,Abducens, Facial, Vestibulomorot, Glossopharyngeal, Vagus, Accessory, Hypoglossal
Olfactory purpose
Smell
Optic nerve
Vision, afferent pathway for pupil
Occulomotor
Superior, inferior, medial rectus, inferior oblique, levator palpebrae, efferent pathway for pupil
Trochlear
Supperior oblique
Trigeminal
Face sensation, muscle of mastecation
Bulbar nerves
9-12 i.e. nerves that come out of the medulla (the bulb(
Abducens
Lateral rectus
facial
Muscles of expression, stapedius, sensation ant 2/3rds tongue
vestibulocochlear
Hearing and balance
Glossopharengeal
Sensation of middle ear- posterior 1/3 tongue. Some swallow
Vagus
Sensation fo the pharynx, larynx, oedophagus, thoracic and abdo viscera. motor of soft palate
Accessory
Sternocleidomastoid and trapezius
Hypoglossal
Tongue movement
How to differentiate a MLF lesions
Medial longitudinal fasciculus: unable on command to look to the medial portion i.e. 6th nerve to 3rd nerve on contralateral side not communicating. STILL ABLE TO CONVERGE as 3rd to 3rd reflex without issue. The side that can’t move is the side that the lesion is on
Intranuclear opthalmoplegia
INO lesion - meaning that on adduction of the eye, the eye is unable to adduction but can conjugate gaze. Issue with the side that is affected. MLF lesion
“Cross signs” rule of thumb
Highly likely brainstem localisation
Typical laterally medullary syndrome
Bulbar signs, horners, ipsilateral numberness (large CN5 nucleus), occasionally disinterested with dysmetria due to PICA infarct.
Area postrema, location and purpose
The area postrema, a paired structure in the medulla oblongata of the brainstem, is a circumventricular organ having permeable capillaries and sensory neurons that enable its dual role to detect circulating chemical messengers in the blood and transduce them into neural signals and networks.
Five classical lacunar syndrome
Pure motor, ataxic hermiparesis, dysarthria/clumsy hand, pure sensory, mixed sensorimotor
Pure motor stroke
Lacunar stroke, 30-50% of lacunar strokes. Posterior limb of internal capsule
Lacunar Pure sensory
Thalamic infarct
Lacunar ataxic hemipareiss
Post. limb of internal capsule, basis pontis and corona radiata. Combination of cerebellar and motor symptoms
Lacunar Dysarthria location
Basis pontis
Mixed sensorimotor lacunar
Thalamus, posterior limb of internal capsule
Staccato progression with drop in GCA
Basilar stroke
Leg > arm stroke blood supply
ACA territory. Often get urinary problems as pelvic floor muscles knocked off
Alexia without agraphia location
Often hemianopia - i.e. occipital lesion. Posterior cerebral artery, specifically the collosal branches
Location of spinal nerves
Come out above the vertebrae in the C spine, below past that as there is a C8 nerve but no vertebrae
Spinal cord posterior vs. anterior
Posterior horn/root is sensory, anterior is motor.
Posterior collumn
Proprioception and vibration. Decussatie in the lower medulla
Spinothalamic tract
Pain and temperature. decussate immediately
Dorsal root ganglia
Home of the sensory bodies
Corticospinal tract
Descending motor fibers - Also decussate int eh lower medulla
Brown-sequard lesion
Hemi-disection of the cord: Loss of ipsilateral motor and dorsal column + loss of pain and temp on contralateral side
Central cord syndrome
AFFECTS the crossing fibers at that level - but NOT the tracts. Classic is the formation of a syrinx post traumatically
Vascular supply of spinal cord
a single anterior and two paired posterior arteries.
Anterior cord syndrome
Lose everything except the dorsal collumn (proprioception and vibration)
How to look at MRI
T1 first: Grey is grey, white is white, CSF black
T2 image: Grey matter is lighter and white matter is greyand CSF white
T2 flair: suppressing intensity of T2, CSF is not black
T1 image good for
Anatomical pathology
T2 and flair use
T2 for acute pathology such as inflammation, infarct etc.
DWI use
Stroke, mismatch ‘wild water is white’
ADC use
ADC decreased intensity in stroke which matches the DWI mismatch
SWI use
Used for blood - very sensitive. Appears like a black dot for haemorrhage or blood. Picks up on iron
Omega sign
Omega sign is the central sulcus - i.e. the line delineating the frontal lobe
MCA artery branching position
Sylvian fissure
Front abutting the region of the anterior or genu of corpus collosum
Location of the Caudate, to the side of this is the putamen and globus pallidus. (lenticuloform nucleus)
‘Micky mouse’
Midbrain on MRI
Micky mouse eyes
Red nucleus - mouth is aqueduct
Most common transverse myelitis
MS
NMO antibodies
Neuromyelitis optica
Optic neuritis
Loss of colour vision, pain on eye movement, decreased visual acuity, cecocentral scotoma, relative afferent pupillary defect
Relative afferent pupillary defect
Swinging torch test and efferent affect of affected eye overwhelms with the UNAFFECTED eye dilating inappropriately
HLA associated with MS
HLA DR2 and DRB1*15
Common strong risk factor association with MS
EBV strong, smoking, latitude (further from the equator the higher the risk)
Vit D protective
Pathophysiology of MS
Early axonal loss, involving cortical grey matter lesions. B and T cells involved. Progression starts from the onset of disease
Definition of MS
Need dissemination of MS in time and space: meaning, progression and multiple lesions within a space.
Criteria used for 1st clinical presentation in MS
McDonalds criteria
Specific clinical finding for MS
Bilateral INO. Also think of it in trigeminal neuralgia
How many CIS progress to MS
63% - abnormal evoked potentials, younger age, OCBs all higher risk
20% first clinical event in MS is
Optic neuritis - if normal MRI-B have 25% of MS, if abnormal MRI-B then 70% risk
Radiology in MS
T2 flair white matter lesions. T2 hyperintense, T1 hypointense.
Dissemination in space with 1 or more T2 lesions in at least 2 of the following 4 areas:
Periventircular, cortical, infratentorial, spinal cord
Dissemination in Time
New T2 and or Gad enhancing lesion on follow up MRI. Simultaneous enhancing of an enhancing lesion.
Primary Immunoglobulin of the CSF
IgG. OCBs is the increase of IgGs, can also occur with severe disruption of the bbb. Non-specific however does fit for MS. It can also be used to define dissemination in time - they take time to occur
Acute treatment MS
Corticosteroids (1g IV methylpred. 3 days) No benefit from oral steroid tail.
Can now give oral methylprednisolone: 1g methylprednisolone for 3 days in form of pred
In severe attacks, plasmapheresis is the go.
Long term treatment MS
New model is efficacy>safety
Monoclonal antibodies are the most efficacious
Dimethyl fumarate MOA
MMF up-regulates the Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway
Leflunomide MOA
nhibiting the mitochondrial enzyme dihydroorotate dehydrogenase (DHODH)
Fingolimod MOA
Sphingosine-1-phosphate receptor modulator. Inhibits migration of T cells from Lymphoid tissues into CNS and peripheral circulation
Can induce arrythmias
Also can cause high risk of rebound relapse - ensure that when stopping or ceasing that something else is onboard
Ozanimod is the same MOA but only subtypes 1 and 5
Natalizumab MOA
Alpha4beta1-integrin inhibitor. This blocks the function of the integrin, which typically helps lymphocytes cross the BBB
PML definition
Sub-acute progressive demyelinating process to the JC virus (john-cunningham virus)
50-60% of population have this virus, no issue in immunocompetant people
Destroys oligodendrocytes leading to demyelination.
Associated with natalizumab use.
20% mortality
PML presentation
Subacute deterioration of visual, motor or cognitive change. T2 hyperintensities enlarging. No gad enhancement. Cease Natalizumab (plasma exchange to remove) CSF for JCV
IRIS definition
Immune reconstitution inflammatory syndrome: paradoxical deterioration in clinical status attributed to recovery of the immune system vital for controlling JCV (also occurs in HIV or other immunocompromised states)
Alemtuzumab MOA
Targets CD52 expressed on lymphocytes and monocytes and causes a rapid profound lymphopenia.
Increased risk of all autoimmune conditions
Ocrelizumab MOA
CD20 reducer with presenvation of lymphoid stem cells. Similar mechanism to rituximab
First trial that was proven to be efficacious against Primary progressive MS rather than RR MS
Best predictor of MS during pregnancy
Activity of disease pre-conception is the highest predictor of relapse
Safe MAB in pregnancy
Ritux or ocrelizumab in the first trimester - not 2nd or 3rd
Neuromielitis optica Spectrum disorder (NMOSD)
AKA Devics disease: longitudinal transverse myelitis with optic neuritis. B cell disease. Targets astrocytes. Longitudinally extensive.
Necrotic spinal cord
NMOSD prognosis
50% blind and 50% at 5 years unable to walk
NMOSD atibody
75% sensitive and 99% specific for NMO is AQP4 antibody
MOG antibody 50% of all AQP4 negative cases. Poor response to ritux.
Test in serum not CSF
NMOSD treatment
PLEX, methylpred: long term therapy, aza and mycophenolate antiquated now. MAB use (Eculizumab, inebilizumab, satarizumab)
Eculizumab MOA
Terminal compliment inhibitor: Must have meningicoccal vaccine. Risk of encapsulated organisms.
Only given to AQP4 +ve patients.
ADEM
Monophasic disorder that affects the brain and occasionally the spinal cord. Usually preceded by viral infection or other systemic infection. Usually resolve after 3 months.
Big chunky lesions on MRI
Parminson pathophysiology
Alpha-synuclein is a protein that, in humans, is encoded by the SNCA gene. It is deposited in peripheral nerves in parkinsons. It eventually migrates to central system
BRAAK stages
Parkinsons stages Pre-symptomatic Anosmia, constipation, REM sleep behaviour Symptomatic: (3-4 stage) Parkinsonism Late - stage 5-6 neuropsych features
Diagnosing criteria for parkinsons
Decrementing bradykinesia + rigidity or 4-6 hz rest tremor
Difference between spasticity and rigidity
Spasticity is a spinothalamic or central lesion and is Rate or velocity dependant.
Rigidity is a constant without velocity dependance
Palilalia
Repetition of a phrase or word with increasing rapidity
Synucleopathies
LBD, parkinsons, MSA
Treatment parkinsons
Levodopa with dopa decarboxylase inhibitor. Dopamine produces a lot of peripheral side effects - so needs to make it centrally without being broken down.
Three motor phases of parkinsons
On Well treated
Off Undertreated
Dyskinesia - over treated.
Non-ergot Dopamine agonists
Newer dopamine agonists are known as non-ergot. These are pramipexole, ropinirole, rotigotine and apomorphine. Rotigotine comes as a PATCH
Side effects of Dopamine agonists
Impulse control disorders and pundits
Selagiline and raseagling
MOA B inhibitors: as effective as dopamine agonists if not slightly better
Treatment paradigm Parkinsons
Young = MAO I
Most patients LCOPA
Too parkinsonian increase dose
Advanced stages of Parkinsons milestones
Unable to draw intersecting pentagons
TAU-opathy
PSP (syndrome of posutral instability, supranucleua palsy and dementia)
CTE (Chronic traumatic encephalopathies)
Alzheimers
Supranuclear gase palsy
Slowed vertical saccades are most specific feature
Specific down gaze palsy
Eye signs poor sensitivity aside from saccades. Blink rate decreased and over activation of frontalis.
Multisystem atrophy symptoms and cause
Alpha synucelin disorder: autonomic dysfunction, tremors, slow movement, muscle rigidity, and postural instability
Fragile X ataxia/tremor syndrome
FMR1 protein deficiency
Huntingtons disease
Autosomal dominant. Trinucleotide repeat gene.
Triad of Psychiatric, motor and cognitive
Serotonin syndrome
Mental status change, neuromuscular activity (resembles upper motor neuron), autonomic hyperactivity.
SSRI, SNRIs, MOAs, TCAs
Neuroleptic malignant syndrome
Secondary to antipsychotics: rapid escalation of abrupt cessation of anti-psychotics or parkinsons: autonomic dysfunction, lower motor neurons signs.
