SCP2 Flashcards
The ultimate goal of performing a CN examination is to
…localise the lesion
Visual acuity and colour perception is attributed to CN _____
II (Optic)
The “Jaw jerk” reflex tests which cranial nerve?
V (Trigeminal)
Which two cranial nerves are responsible for soft palate elevation?
IX (Glossopharyngeal) and X (Vagus)
A defect in the motor branch of CN IX or X could result in a deviation of the uvula (towards/away from) the side of the lesion.
AWAY from
(Remember: “Push it towards, Pull away”
How is CN X (vagus nerve) tested in the cranial nerve exam?
Elevation of uvula, cough, gag (reflex)
Which cranial nerves could be involved in nystagmus?
III (Oculomotor), IV (Trochlear), and VI (Abducens)
If a patient presents with issues related to visual acuity or colour perception, where is the most common site of the problem?
Most likely an ocular or retinal problem
A defect in the inner retina/optic nerve/visual pathway results in ________ defects
red/green
What type of colour defects are associated with outer retinal diseases?
blue-green defects
Visual field defects most commonly localize in the _______ ____________.
cerebral hemispheres
What is the medical term for “unequal pupils?”
Anisocoria
Aniridia refers to an abnormal ______
iris
What is the pretectal nucleus of the midbrain associated with CN III and the pupillary light reflex?
The Edinger-Westphal nucleus
A “Marcus-Gunn Pupil” refers to what type of pupillary defect?
A relative afferent pupillary defect.
This is a condition where one optic nerve is relatively defective compared to the other. The defect causes info to travel slower along the optic nerve, so it will not respond as quickly to the light stimulus, so there is a delay in constriction on one side.
AFFERENT PUPILLARY DEFECT = SLOWER SIGNALLING
What is a classic cause of a relative afferent pupillary defect?
Optic neuritis- think MS.
What is located at the head of the optic nerve?
the optic disc
Blurred margins or swelling of the optic disc are indicative of what condition?
Raised intracranial pressure
The eye movement pathway begins with afferent fibres traveling via CN II (optic nerve), which arrive to the ________ _________ nucleus –> visual cortex –> prefrontal cortex –> midbrain EW/CN III nucleus –> Efferent fibres of CN III and V1
lateral geniculate
Which muscle of the eye is responsible for the “down & out” (inferolateral) movement of the eyeball?
Superior oblique muscle
Which four eye muscles connect to the common tendinous ring?
All 4 recti muscles
Damage to which cranial nerve will result in the eye appearing “down and out” and ptosis?
CN III (Oculomotor)
An irregularly shaped pupil represents what type of injury?
surgical
In a CN IV (trochlear) defect, the head will be tilted (towards/away from) the affected side
away from
If CN VI (Abducens) is working normally, the sclera around the lateral iris should _________ on lateral gaze.
disappear
Where is the most likely site of a defect presenting with monocular diplopia (double vision in one eye)?
intraocular defect
In the case of horizontal binocular diplopia (double vision in both eyes) where is the most likely site of the defect?
Lateral/medial rectus
Multidirectional nystagmus suggests dysfunction in which area?
the cerebellum
If there is a defect in CN (___), which innervates the pterygoid muscles, the jaw will deviate TOWARDS the affected side
V (Trigeminal)
Is the “jaw jerk” reflex a normal or an abnormal finding when testing CN V (trigeminal)?
An abnormal finding- jaw jerk should not be present
What is “Bell’s phenomenon?”
Bell’s phenomenon is a medical sign of Bell’s palsy that allows observers to notice an upward and outward movement of the eye, when an attempt is made to close the eyes.
Which cranial nerve supplies the parotid gland?
CN IX (Glossopharyngeal)
Which half of the face is affected in a stroke?
Only the lower half
In Weber’s test, a person with sensorineural hearing loss hears the sound better in their right ear. This reflects a defect on which side?
The patient’s left side. In Weber’s test, the tone is referred to the patient’s better ear in sensorineural hearing loss, with indicates impairment in the contralateral ear.
The innervation of which cranial nerve is from the medulla to C5?
CN XI (Spinal accessory)
When the left SCM muscle contracts, the head turns to the ________
right
Dysmetria (dysdiadochokinesis), nystagmus, and slurred speech are signs of a defect in which area of the brain?
the cerebellum
Problems with speech articulation are known as _____- and involve which four cranial nerves?
Dysarthria
CN’s 7, 9, 10, and 12
How is power affected in UMN lesions? Preferentially affects _________ in arms, and __________ in legs
Extensors, flexors
Wasting and fasciculations are signs of _____ lesions.
LMN
What is the pattern of wasting distribution in myopathies vs neuropathies?
Myopathies: proximal muscle wasting
Neuropathies: distal muscle wasting
Medical term for “wild flinging movements”
Ballism
Semi-purposeful abnormal movements
Athetosis
Sustained abnormal contraction of muscle
Dystonia
Brief jerks of the muscle
Myoclonus
Sustained clonus (> 6 jerking movements) is indicative of a/an ______ lesion
UMN
__________ rigidity is a classic sign of Parkinson’s disease, and is a sign of an _____________ disorder/
Cogwheel, extrapyramidal
What is the muscle, nerve, and nerve root involved in shoulder abduction?
Deltoid, axillary nerve, C5
Muscle, nerve and nerve root for testing elbow flexion (upper limb power)?
biceps, musculocutaneous, C5/C6
Muscle, nerve, nerve root for testing elbow extension (upper limb power)?
Triceps, radial, C7
Muscle, nerve, nerve root for wrist extension?
Extensor carpi radialis longus, posterior interosseous nerve, C6
Muscle, nerve, nerve root for hip flexion?
Iliopsoas, iliofemoral nerve, L1/L2
Muscle, nerve, nerve root for hip extension?
Gluteus max, sciatic, L5/S1
Muscle, nerve, nerve root for knee flexion?
Hamstrings, sciatic nerve, S1
Muscle, nerve, nerve root for knee extension?
Quadriceps, femoral nerve, L3/L4
Muscle, nerve, nerve root for dorsiflexion of the foot?
Tibialis anterior, deep peroneal nerve, L4/L5
Muscle, nerve, nerve root for plantar flexion of the foot?
Gastrocnemius/soleus, tibial nerve, S1/S2
Nerve root levels for upper limb reflexes: (Biceps, supinator, triceps)
C5: Biceps
C6: Supinator
C7: Triceps
Nerve root levels for lower limb reflexes: (knee jerk, ankle jerk)
Knee jerk: L3/L4
Ankle jerk: S1
What is the distribution of sensory impairment in peripheral neuropathy?
“glove and stocking” distribution- longer nerves are affected first
Impaired pain and temp sense on the right side, impaired light tough and vibration sense on the left side. Pyramidal weakness, increased tendon reflexes in left leg, and extensor plantar response on left side. Light touch causes exquisite pain. These are symptoms of _____________ syndrome.
Brown-sequard
Sensory impairment of thumb, first and second fingers and part of third finger, motor impairment of abductor pollicis brevis and opponens pollicis describes what type of peripheral nerve lesion?
Carpal tunnel syndrome
Nerve affected in carpal tunnel syndrome?
Median
Sensory impairment on dorsolateral aspect of hand, impaired extension of fingers and wrist describes which peripheral neuropathy?
Radial nerve palsy
Sensory impairment of medial aspect of ring & little fingers, impairment in small muscles of hand (hollowed out “LI4”)
Ulnar nerve palsy
A sensory impairment that mainly affects the foot and toe dorsiflexors (“Strawberry pickers”) involves which nerve?
Common peroneal
A patient with a loss of proprioception- more unsteady with eyes closed than with eyes open, is known as a positive __________ sign and is indicative of a defect in the ___________.
Romberg’s, cerebellum
“Steppage gait” is associated with what type of lesion? (UMN/LMN)
LMN lesion
