Neuro Flashcards
Motor pathway description?
Primary motor cortex -> UMN moves to medulla here 90% lateral corticospinal tract decussate and 10% dont anterior corticospinal tract -> Move down until they reach the correct spinal level at which they synapse with the LMN which innervates the relevant muscles
Corticospinal tracts aka pyramidal tract
What is UMN leisons, what about LMN - motor?
UMN:
Brain
Brainstem
Injury to white matter of spinal cord up to level of synapse
LMN:
Injury to grey matter at the level of the synapse (anterior horn) + injury to axons leaving the spinal cord
Why do you get the sx you do in UMN leisons?
There is no UMN control of the LMN hence this response is NOT controlled
What are UMN and LMN sx?
What are some possible differentials for Hemiplegia?
Vascular:
- Stroke
- TIA (signs would last less than 24h and no evidence of infarction upon brain imaging)
SOL
Demyelinating conditions eg MS
- Signs and sx disseminated in time + space (can be motor, sensory and cerebellar)
What ix would you like to do further support stroke dx?
- CN exam - may notice eyebrow sparing facial nerve palsy
- Assess CV RFs - checking for signs of AF, carotid bruits and check for any heart murmurs
How can strokes be classified?
Due to pathophysiology:
- Ischaemic
- Haemorrhagic (15%)
Bamford classification - location:
- Total anterior circulation stroke - highest mortality
- Partial anterior circulation stroke
- Posterior circulation stroke
- Lacunar stroke
Describe the sensory pathway:
Involves Dorsal column (touch, vibration and proprioception) and Anterolateral spinothalamic (pain and temprature) tract
What are the possible causes of Peripheral Neuropathy?
Predominatlty sensory:
ABCDE
Alcohol and diabetes = most common
Vit B12 deficiency
Chronic renal failure + Ca (paraneoplastic)
Drugs eg isonisaid or vincristine
Every vasculitidies (eg SLE) + Everything else (eg paraneoplastic)
Predominantly motor:
- Charcot Marie Tooth - both sensory and motor however more likely motor -> young, high arched foot and champage bottle lower limbs mutation in PNP22 gene
- GBS - if acute
- Chronic inflammatory demyelinateing polyneuropathy - if more chronic
How can you ix peripheral neuropahty?
Bedside:
- Blood glucose
- Urine dip - check for glucose
Bloods:
- DM - fasting glucose, HbA1c
- Alcoholc - FBC, LFTs, clotting
- Chronic renal failure - U+E
- Vitamin deficiency - B12 and Folate
- Vasculitidies - ESR and autoantibody screens
Imaging:
- Consider XR and CT imaging to check for paraneoplastic features
Special tests:
- Nerve conduction studies
- Gene - PMP22 in CMT
What are some possible dx for MS and why?
What are the possible signs of MS?
Describe what is INO?
Leison is in the eye that cannot adduct (go in) due to pathology in medial longitudinal fasiculus
What are the different types of MS?
Mx of MS?
What are the other types of Parkinsonianism?
Mx of Parkinsons?
What are some possible causes of proximal myopathy?
What to do next when you have a pt and you suspect proximal myopathy?
What are the further ix to do in proximal myopathy pt?
What are the causes of Cushings?
What are the signs and sx of cushings syndrome?
What are some possible causes of Ptosis?
Elevation of eyelid involves - levator palpebrae superioris (3rd nerve) + superior tarsal muscle (sympathetic control)
What should you do next in a pt w/ unilateral ptosis?
Myotonic dystrophy presentation
What extra tests are needed for myasthenia gravis + present that pt?
Present findings in a CMT disease?
