Neuro - exam findings Flashcards
(22 cards)
Tremor in PD
More pronounced with mental effort (count backwards from 20)
Asymmetrical (ie this supports PD not parkinsonism)
Tone/Rigidity - types
Lead pipe rigidity - increased tone throughout passive movement
Spasticity (UMN) - increased tone at onset, decreases suddenly throughout
(Cogwheeling is combo tremor & rigidity) - at wrists & ankles
Synkinesis - voluntary movement in other arm increases rigidity
Parkinsons exam - notable tests to move onto
- Bradykinesia (by opening/closing hand & in foot tapping)
- Gait
- Glabellar tap not reliable
- Gaze palsies
- Assess for seborrhoea/seborrhic dermatitis
- Micrographia
- Postural BP
- Cognitive (minimental)
Posture in PD
Stooped
Due to rigidity causing slightly more flexion than extension
Gait in PD
- Stooped, shuffling
- Narrow base
- Difficulty initiating & turning
- Reduced arm swing
- Note accentuated hand tremor
Tremor - essential v PD
Essential: symmetrical, worse w/ voluntary movement, not head
Parkinsonism: not head (can be tongue, jaw etc) + postural component
If write - PD tremor subsides (micrographia), ET tremor & writing enlarges
UMN sx
- UL drift
- Facial weakness
- Babinski reflex (down)
- (Hemiparesis)
- Wrist extensor weakness
Not mm wasting (although from disuse can have some atrophy)
All mms weaker but particularly UL ext & LL flex (& abductors of both)
UMN level
- Leg involved: L1 or higher
- Arm involved: C3 or higher
- Face affected: Pons or higher
- Diplopia: Midbrain or higher
Lesion interruped above anterior horn cell (SC is continuation of brain)
Describing limb paralysis
UMN fx (as SC is brain)
- Monoplegia: 1 limb (eg motor cortex or internal capsule lesion)
- Hemiplegia: 1 side (pathways from contralat motor cortex)
- Paraplegia: both legs
- Quadraplegia: all limbs (usu SC trauma, rarely brainstem lesion)
VF - defect & aetiology
BITEMPORAL HEMIANOPIA
Optic Chiasm lesion
eg. Vasc tumour.
Pituatary tumour, Craniopharyngioma, Suprasella meningioma
Damages both temporal halves of retinas as they decussate
VF - defect & aetiology
CENTRAL SCOTOMA
Optic nerve head to chiasmal lesion
Can be unilateral/bilateral
- Demyelination of optic nerve (MS can be uni/bi)
- Toxins (methyl EtOH - bilat), nutritional
- Vasc lesions (unilat) & Gliomas of optic nerve (unilat)
VF - defect & aetiology
HOMONYMOUS HEMIANOPIA
Optic tract lesion (same visual field R/L) to occipital cortex (ie after chiasm)
Ipsilateral to nasal visual field loss - as hits temp retina & doesnt cross
Maybe macular sparing if posterior cortical ischaemia (as macular cortex has additional vasc supply from MCA, ACA). If in tract, no macular sparing.
eg. Vasc (CVA), tumour etc
VF - defect & aetiology
LOWER QUADRANT HEMIANOPIA
Lesion in parietal lobe (as optic tract splits passing through here)
eg. Vasc/Tumour
VF - defect & aetiology
UPPER QUADRANT HEMIANOPIA
Lesion in temporal lobe (as optic tract splits passing through here)
eg. Vasc/Tumour
VF - defect & aetiology
TUNNEL VISION
Concentric diminution
- Glaucoma
- Retinal abN (chorioretinitis, retinitis pigmentosa)
- Papilloedema
- Acute ischaemia (inc migraine)
VF - defect & aetiology
UNILATERAL VISUAL LOSS
- Lesion of optic nerve
(optic neuritis, ICA occlusion) - Unilateral eye dis
(CRAO/CRVO, retinal detachment, vitreous haemorrhage)
Dx & aetiology/mechanism
CN 3 (oculomotor nerve) PALSY
- Ptosis (usu complete) - Levator palpebrae inactivated
- Mydriasis - dec tone of pupillary constrictor mm
- Divergent strabismus - unopposed superior oblique & lateral rectus mms (“down & out”)
Aetiology:
- Central: vasc lesions in brainstem, tumours (demyelination rare)
- Peripheral: compressive lesions (aneurysm at PCA), tumour, orbital lesion, ischaemia/infarction (inc migraine, DM, arteritis), meningitis
Eye movements & CN
3 (lesion in 3 means eye is down & out) except: SOD’s LAW (4 → 6)
- Superior oblique (4) which move both eyes DOWN & in - SOD
- Lateral Rectus (6) which move both eyes OUT horizontally - LOR
- Nb oblique mvmnt opposite eg superior moves dwn, inferior move up.*
- With LR movement is same, SR is up & out, IR is down and out*
- Abduction is away from nose, Adduction is to nose*
INO - MoA (where is lesion & how)
Medial longitudinal fasiculis (CN6 LR to CN3 MR)
When you converge eyes, should coordinate (as both MR)
But if go to look in direction of lesion -
If INO lesion - then ipsilat eye stays midline - doesn’t move medial (CN3)
Other side moves but nystagmus
Who? MS if young (highly myelinated), CVA if old (differentiate w/ timeframe)
Vision - fields to brain pathways
Vision crosses to other side of lens in eye (temporal v nasal retina)
Then down that optic nerve (pre-chiasmal) - lesion here = unilateral
Nasal retina crosses at optic chiasm (post chiasmal lesions = bilateral)
Means joins with the other eye - same side of vision to go to LGN then occipital
CN4 lesion (rare so theoretical)
& how to check this
CN4 - superior oblique (down & into nose)
On affected side - when looking laterally - ok.
When looking in - eye gets pulled upwards by inferior oblique
Head tilt test - pt walk around w/ head tilted away from lesion (to opposite shoulder) - allows binocular vision
Usu idiopathic or traumatic (lesions cerebral peduncle)
CN6 lesion - fx & aetiology
CONVERGENT STRABISMUS (failure of lateral mvmnt) + DIPLOPIA
Maximal on looking to affected side
Can be uni / bilateral
Unilateral: idiopathic, trauma.
Central (vasc or tumour) or Peripheral (raised ICP, DM)
Bilateral: Trauma, Wernickes, Mononeuritis multiplex, Raised ICP
