Lectures 3 + 4 - Neurological Exam Flashcards
What is assessed in a neurologic examination?
MCMRCS
- Mental State
- Cranial Nerves
- Motor Exam
- Reflexes
- Coordination and Gait
- Sensory Exam
What is assessed in the mental state exam?
- Glasgow coma scale
- level of alertness, attention
- orientation - check if they know where they are
- memory - anterograde, retrograde
- language
- delusions and hallucinations
- mood
What is the glasgow coma scale?
Asks three questions:
- Opening of eyelids
- Motor responses
- Verbal responses
max score = 15
concerning score = 8 and below
What could cause a deficit in levels of alertness, attention and cooperation?
- assess by digit span, or spelling short words backwards
- damage to BRAINSTEM, bilateral lesions of THALAMI or CEREBRAL HEMISPHERES impaires CONSCIOUSNESS
- different focal brain lesions, diffuse abnormalities, dementias and encephalitis, behavioural and mood disorder
What would cause a loss of short term memory?
damage to LIMBIC STRUCTURES
What causes problems in language?
Lesions in BROCA’S AREA and WERNICKE’S AREA - dominant frontal lobe, left temporal and parietal lobes.
Thalamus also indicated
What causes neglect?
Test for extinction on double simultaneous stimulation
- lesion on right parietal lobe
- lesion on right thalamic or basal ganglia
both causes neglect on left side.
What can delusions and hallcucinations implicate in a neurological examination?
- toxic or metabolic abnormalities
- psychiatric disorder
- focal lesions or seizures in visual, somatosensory auditory cortex.
- lesions in association cortex or limbic system
What can mood problems implicate in neurological examination?
disorder of neurotransmitters
possibly lesion in thyroid
How do we examine CN I?
- smell - peanut butter, coffee, soap
- closed head TBI
- olfactory groove meningioma
- etc
How do we examine CN II
- using an opthalmoscope to check retinas
- Visual acuity using eye chart one eye at a time
- map visual field using fingers
- visual extinction - can they see out of each eye
Where in the eye mostly has cones?
Fovea
this is where colour vision occurs
fovea has a big representation in brain
What is the optic cup?
This is the blind spot, and is where all the nerves converge.
Raised intercranial pressure will show cupping out of blind spot- it will become CONCAVE
What are the different lesions that can occur to CN II, and how will it present?
In front of the optic chiasm - will affect the ipsilateral eye
Behind the optic chiasm - will affect the contralateral visual FIELD in both eyes
How do we examine CN II and III
- Pupillary responses
Note size at rest, then see if they constrict in light, and accomodate (eyeballs move inwards when looking at something moving closer) - check for consensual puppilary response - other eye pupil also responding.
PERRLA
What would cause problems in the pupillary response or consensual response?
ipsilateral optic nerve lesions, ipsilateral parasympathetics travelling in the CN III, or problems in pupillary constrictor muscle or iris
contralateral optic nerve for consensual response
How do we examine CN III, IV, VI?
convergent eye movements
smooth eye movements in all directions
abnormalities in individiual eye muscles, or specific cranial nerves
indicates lesions of cerebellum
How do we examine CN V
trigeminal nerve
facial sensation and muscles of mastication
use cotton swab or safety pin
How do we examine CN VII
can be seen in weaknesses or asymmetry between sides of face
can also ask them to smile, frown etc.
taste
lesions in UMN in contralateral motor cortex, descending motor pathways, LMN in ipsilateral facial nerve nucleus, faicla muscles.
eg. stroke - UMN
How do we examine CN VIII
hearing and vestibular sense
- gently rub fingers outside ear
vestibular sense is generally not tested unless patients have vertigo etc.
problems with hearing can result from lesions in the acoustic nerve, or neural elements in the ear, such as cochlea
How do we examine CN IX AND X
palate elevation and gag reflex
does the palate elevate evenly when they say ‘aah’
- gag reflex is only tested in patients with suspected brainstem lesions, impaired consciousness or impaired swallowing.
How do we examine VI, VII, IX, X and XII
muscles of articulation
- just listen to the patient speak.
have there been changes?
slurred, hoarse, nasal, low or high, breathy etc.
speech articulation can be affected in lesions of muscles of articulation, neuromuscular junction, or peripheral or central portions of V, VII, IX, X and XII.
How do we examine CN XI
- Sternocleidomastoid and trapezoid muscles
- assessed by asking to shrug shoulders, turn head side to side etc
- weakness can be caused by lesions in muscles, neuromuscular junction, LMN of the CN XI
check back on slide
How do we examine CN XII
- tongue muscles - are there any fasciculations?
- ask to stick tongue out and move it around.
Fasciculations - LMN damage.
Where do upper motor neurons project to?
precentral gyrus
all the way to the pons
Does upper motor neuron damage cause atrophy?
No!!
because the connection between the UMN and LMN is fine, which actually innervates the muscle…
What differentiates between acute and chronic UMN lesion presentation?
Acute - flaccid, paralysis, decreased tone.
Chronic (with time) - hyper tonnicity, hyperreflexia
What is drift?
having the patient hold up both arms or legs and then they close their eyes
What do reflexes test for?
LMN lesions, as it goes to the spine and back to the muscle.
Name some reflexes that are often tested
- deep tendon reflex
biceps reflex
brachioradialis reflex
triceps reflex
patellar reflex
achilles reflex
abdominal reflex
- plantar response
they are graded 0 - 5
5 is sustained clonus.
What are frontal release signs?
frontal lobe lesions can sometimes cause the re-emergences of some primitive reflexes that were present in infancy
What is ataxia?
abnormal movement, seen in coordination disorders.
involuntary movements, overshoot…
What is dysdiadochokinesia
an abnormality in rapidly alternating movements.
eg. finger to nose test.
caused by cerebellar lesions, but depends on WHERE the lesion is in the cerebellum.
how do we test Appendicular coordination?
this is testing rapid alternative movements, past pointing, ataxia.
finger to nose test
rapidly toughing thumb to other fingers.
How can you distinguish that an abnormality is due to cerebellar lesion
Normal performance on motor tasks requires multiple sensory and motor pathways, including proprioception, LMN, UMN, basal ganglia and cerebellum.
Thus, you need to test all of the both, including vision and strength, and confirm it is not a LMN problem, or involuntary movement caused by basal ganglia lesios.
What is the romberg test?
Patient is asked to stand with their feet together, and with eyes closed.
See if they start to sway or fall.
This will indicate damage to proprioceptive or vestibular pathways, or to the midline cerebellum…
What can gait tell us?
problems with walking, heel to toe on the floor –> truncal ataxia, from lesions in the midline cerebellum
What are the types of touch examined in the sensory examination?
light touch - test divisions of the trigeminal nerve
and vibratory sensation
temperature sensation
What is Astereognosis?
unable to identify an object in their hands. eg. keys.
stereognosis - ability to do this.
What is agraphaethesia
inability to identify figure … drawn on their palm
What are somatosensory deficits caused by?
- lesions in the peripheral nerves
- nerve roots
- posterior columns or ventrolateral sensory pathways in SC
- lesions in brainstem, thalamus or sensory cortex.
can distinguish according to what kind of sense - pain and temperature cross in the SC much earlier,
In tact primary sensation but deficits in cortical sensation - graphaestsia, stereognosis = lesion in contralateral sensory cortex.
