Neurology - Basic Neuroanatomy and Physiology Flashcards
Blood supply to medial surface cerebral hemisphere
Anterior cerebral aa
Blood supply to lateral 2/3 brain
Middle cerebral aa
What do the central branches of the middle cerebral aa supply/
Corpus striatum
Thalamus
Internal capsule
What does the posterior cerebral aa supply
corpus callosum
occipital and temporal lobes
Which arteries supply the brainstem and cerebellum
Vertebral aa
Basillar aa
Location olfactory nn
Olfactory epithelium
Function CN I
Sensory - smell
Location optic nn
Retinal ganglion
Function CN II
Sensory - vision
Function CN III
Motor - 4/6 extraocc mm + LPS
Visceral - pupil constriction
Function CN IV
SO mm
Location CN III and IV
Midbrain
Function CN V1
Ophthlamic
SUperior 1/3rd sensation
+ cornea
Function CN V2
Maxillary
Middle 1/3rd sensation
Function CN V3
Mandibular
Bottom 1/3rd sensation
Mm mastication
Function CN VI
LR mm
Function CN VII
Motor - facial expression. Visceral glands (SM,SL and lacrimal)
Sensory - ant 2/3 tongue, around ear
Location CN V, VI and VII
Pons
Function - CN VIII
Balance
Hearing
Location CN VIII
Vestibular ganglion
Function - CN IX
Motor - swallow (stylopharyngeus) and parotid gland
Sensory - post 1/3rd tongue
Function CN X
Motor - soft palate, parasymp of trachea, bronchi, digestive tract
Sensory - taste, epiglottis, sensation viscera
Function CN XI
Motor - SCM and trapezius
Location CN XI
SC
FUnction CN XII
Tongue mm
Location CN IX, X + XII
Medulla
Where in the brain does a bulbar palsy occur
LMN of CN 9, 10 + 12
PS bulbar palsy (5)
Tongue - wasting flaccid + fasciculations Dysphagia Poor elevation soft palate Quiet and nasal speech Jaw jerk + gag reflex absent
Causes bulbar palsy (5)
MND Stroke GBS Infective Neoplastic
Where is the brain does a pseudobulbar palsy occur
Bilateral UMN of CN 9,10,12
PS pseudobulbar palsy (5)
Tongue - stiff/spastic, slow movement Dysphagia Normal elevation SP Donald duck speech Incr jaw jerk and normal gag reflex
Cause pseudobulbar palsy (4)
MND
Stroke
MS
Head trauma
Sx frontal lobe lesion (5)
Intellectual impairment Personality changes Incontinence Paralysis Brocas aphasia
Sx temporo-parietal lesion (left)
Agraphia Alexia Acalculia Wernicke's aphasia Contralateral sensory neglect
Sx temporo-parietal lesion (right)
No face recognition
Contralateral sensory neglect
Sx occipital lobe lesion
VF defects
Fct vermis
Midline posture and balance
Fct flocculonodular lobe
eyes movements
Fct cerebellar hemisphere
Control limb movement
O/E Cerebellar lesion
Dysdiadokinesis Ataxia Nystagmus Intention tremor Speech - slurred, staccato Hypotonia/Heel-shin
Bilateral causes cerebellar dysfunction (4)
Alcohol
Dx - phenytoin, anti-epileptics
Paraneoplastic degeneration
Hypothyroid
Unilateral causes cerebellar dysfunction (3)
MS
Stroke
Tumour - acoustic neuroma, meningioma
Sections of the Basal Ganglia (4)
Corpus striatum
Subthalamic nucleus
Substantia nigra
Thalamus
What 3 things make up the corpus striatum?
Caudate nucleus
Globus Pallidum
Putamen
Function of basal ganglia
Modulates motor activity
Signs Basal ganglia dysfunction
Bradykinesia
Rigidity
Involuntary tremor
What is athetosis
Writhing movements of hands/face/tongue
Causes of BG dysfunction (3)
Parkinsonism
Huntington’s
Hemiballismus
Causes of central scotoma
Macular lesion
Causes of bitemporal hemianopia
Optic chiasm lesion
Causes of homonomous hemianopia
Contralateral optic tract lesion
What area of the brain is Broca’s area
44 + 45
Fct Broca’s area
Motor speech function
Sx Broca’s aphasia
Expressive aphasia (non-fluent)
What area of the brain is Wernicke’s area
Area 22 (temporal)
Fct Wernicke’s area
Understanding of spoken word
Sx Wernicke’s aphasia
Receptive aphasia
Cant understand speech/word salad
What is global aphasia
Expressive AND receptive
What is nominal aphasia
Difficulty word finding
What is dysarthria
Disordered articulation
Slurred speech
Bulbar palsy - dysarthria
LMN, high pitched nasal speech
Pseudobulbar palsy dysarthria
UMN
Donald duck voice
Cerebellar lesion dysarthria
Slow jerky speech
Extrapyramidal lesion dysarthria
Soft monotonous speech
Myasthenia gravis - dysarthria
Speech fatigues + dies away
PS - Horners syndrome (PAMELA)
Ptosis Anhydrosis Miosis Enophthalmos Loss of ciliary-spinal reflex Anisocoria
If Horners syndrome is congenital, what extra sign may the patient have?
Heterochromia (diff eye colour)
1st order neuron - causes Horners syndome (4)
Tumour
Stroke
MS
Syphillis
Anhidrosis - 1st order neurone Horners syndrome
Face/arm/trunk anhidrosis
2nd order neuron causes of Horners syndrome (6)
Pancoast trumour Cervical rib TB Trauma (neck) Lymphadenopathy (neck) Thyroid surgery
Anhidrosis - 2nd order neurone Horner’s syndrome
Facial anhidrosis only
3rd order neurone causes of Horners (3)
ICA aneurysm
Migraine
Idiopathic
Anhidrosis - 3rd order neurone Horner’s syndrome
NO anhidrosis
Signs LMN lesion
weakness wasting fasciculation hypotonia hyporeflexia
Do LMN innervate contralateral or ipsilateral muscles?
Ipsilateral
Causes - LMN lesion (5)
ventral horn - MND Ventral horn - polio Peripheral nn pathology MG (NMJ) Mm pathology
Signs UMN lesion
Extensor weakness upper limb Flexor weakness lower limb No wasting Hypertonia Hyperreflexia Pronator drift Incr plantar response Clonus
Do UMN innervate contralateral or ipsilateral muscles
Contralateral
Causes UMN lesion (6)
Stroke Meningitis MS, MND Tumour Degen - Parksinsons
How to differentiate LMN and UMN facial weakness
UMN - spares frontalis - brow/eye closing + blinking preserved
LMN - ipsilateral facial weakness all mm
Function of spinothalamic tract
Pain
Temperature
Light touch
Which level does the spinothalamic tract decussate at?
Spine
Function of dorsal column
Sensory
Fasciculus, cuneatus + gracilis
Deep touch, proprioception + vibration
Which level does the dorsal column decussate at?
Brainstem
What level does the corticospinal tract decussate at
Brainstem
PS C3 cord transection
Neurogenic shock Resp insufficiency Quadriplegia Anaesthesia below level Loss bladder/bowel sphincter tine Sexual dysfunction Horners ?
PS T10 cord transection
Paraplegia
Anaesthesia below
Loss rectal/bladder tone
Sexual dysfunction
Presentation Brown Sequard syndrome
Ipsilateral decrease in power, vibration + proprioception
Contralateral decr pain/T + light touch
Cause Brown Sequard syndrome
Penetrating injury
Facet dislocation RTA
PS Posterior cord lesion
Tingling, numbness + electric shocks
Clumsy
Sensory ataxia, loss positional/vibrational + 2 point discrim
Anatomical position lumbar puncture
L4 - top of iliac crest
What position is patient in when having a lumbar puncture
Lie on side + knees to chest
Curl over pillow
Indications lumbar puncture (7)
Meningitis/encephalitis SAH MS Neurosyphilis Bechet's Measure/remove CSF - idiopathic intracranial HTN Intrathecal drug admin
Complications LP
Post LP headache Dry tap Infection Damage to spinal nn Coning
C/I Lumbar puncture (5)
Suspicion of incr ICP Overlying/local infection Congenital lesions - meningomyelocele Problems w/ haemostasis Haemodynamically unstable
What is Xanthochromia
Yellowish CSF
Why does xanthochromia occur
B/c RBC breakdown –> bilirubin
Cause xanthochromia
SAH
Features of CSF in MS
Moderate increase in protein
50 lymphocytes/ml
Oligoclonal IgG bands (electrophoresis)
C/I MRI (4)
Implanted devices
E.g. pacemaker, drug infusion pumps, cochlear implants
Implants w/ metal
Bullet/shrapnel