Head to toe- neurology exam revision Flashcards
1
Q
Rombergs Sign, protinator drift and sterogenosis
A
- A positive rombergs sign is used to test for sensory ataxia (non-cerebellar cause of balance issue) causes include hypermobility joint, B12 defiency PD, vistibular neuritis and menieres
- A positive protinator drift indicates corticospinal tract lesion
- Patients will often not be able to identify stroke
2
Q
What are the upper limb myotomes
A
- C4 (Trap raise)
- C5 (Chicken wing)
- C6 elbow flexion
- C7 (Biceps extension)
- C8 (thumbs up)
- T1 (Squeeze little finger)
- Also test grip strength
3
Q
What are the causes of reduced power in upper limbs
A
- Upper motor neuron lesion causes pyramidal pattern of weakness that disproportionally affects upper limb extensors are weaker that flexors in upper limb
- Lower motor neuron lesions- cause a focal pattern of weakness with only the muscle directly innervated by the damaged neurone affected
4
Q
What are upper limb dermatomes
A
- C5- lateral aspect of the lower edge of the deltoid muscle
- C6- side of the thumb
- C7- middle finger
- C8 Little finger
- T1- Inside of humerus
5
Q
Patterns of sensory loss
A
- Mononeuropathies- result in a localised sensory disturbance in the area supplied by the damaged nerve
- Peripheral neuropathy- causes symetrical sensory deficit ina ‘glove and stocking’ distribution in the peripheral limbs. caused commonly by diabetes
- Radiculopathy- occurs due to nerve root damage (compression by a herniated intervertebral disc), resulting in sensory disturbances in the dermatomes
- Spinal cord damage- Results in sensory loss both at and below the level of involvement in a dermatomal pattern due to its impact on the sensory tracts running through the cord
- Thalamic lesions (e.g. stroke)- result in contralateral sensory loss
- Myopathies- often involve symmetrical proximal muscle weakness
6
Q
Causes of anosmia (Olfactory nerve)
A
- Mucous blockage of the nose
- Head trauma
- PD
- COVID 19
7
Q
Causes of decreased visual acuity (CN II Optic nerve)
A
- Optic neuritis
- Lesions high in the visual pathways
- Amblyopia
- Cataracts
- Macular degeneration
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8
Q
Abnormal Pupillary light reflex (CN II optic or CN III Oculomotor)
A
- Relative afferent pupillary defects which is B/L reduced constriction- can be caused by central retinal artery/vein occlusion, retinal detachment, optic neuritis, compression due to tumour/abcess
- Unilateral efferent defects- Compression of oculomotor nerve resulting in ipsilateral pupilary reflex (more dilated/non-responsive). consensual reaction would still occur as CN II would be fine.
9
Q
Visual Feild defect
A
- Monocular visual loss= central retinal artery occlusion, optic neuritis, optic atrophy
- Biltemporal hemianopia- optic chiasm lesion (pituitary tumour)
- Homonymous hemianopia- contralateral optic tract lesion (middle cerebral artery MCA occlusion)
- Homonymous inferior quadrantanopia= contralateral parietal upper optic radiation lesion (Parietal tumour or MCA occlusion)
- Homonymous Superior quadrantanopia= contralateral temporal (lower) optic radiation lesion (temporal tumour or MCA occlusion inferior branch)
- Homonymous hemianopia with macular sparing (Posterior cerebral artery occlusion)
10
Q
CN III, IV, VI nerve palsy (oculomotor, trochlear and abducens)
A
- Damage to any of the three nerves can lead to paralysis of the subsequent muscle
- CN III- eye gets pulled inferolaterally (down and to one side). can cause ptosis and mydriasis (dilation of pupil)
- CN IV palsy- results in vertical diplopia when looking down
- CN VI palsy- results in convergent squint
11
Q
Trigeminal nerve CN V
A
- Trigeminal neuralgia
12
Q
Facial Nerve (VII) palsy
A
- Facial nerve palsy presents with a unilateral weakness of facial muscles can be caused by upper and lower motor neuron lesions
- Lower motor neuron lesion presents with ipsilateral muscles of facial expression, due to loss of innervation to all muscles on the affected side. Commonly is caused by Bells Palsy
- Upper motor neuron lesion also presents with unilateral facial muscle weakness however the upper facial muscles are partially spared becuase of bilateral cortical representation (forehead is maintained) most commonly caused by stroke
13
Q
CN VIII conductive vs sensorineural hearing loss
A
- Conductive hearing loss occurs when sound is unable to effectively transfer at any point between the outer ear and middle ear. causes excessive wax, otitis media/externa, perforated tympanic membrane
- Sensorineural hearing loss- dysfunction of cochlea/ CN VIII- causes age, excessive noise exposure, viral infections, ototoxic agents
14
Q
CN IX
A
- Say Ahhhh- lesion will cause deviation away from lesion
15
Q
CN XI palsy
A
- Weakness in trapezius raise and head and neck turn
