Neuro 1 Flashcards
What are the indications for a head CT in an adult?
CT within 1 hour of risk factor being identified:
- GCS <13 initially
- GCS <15 2 hrs after injury
- suspected open or depressed skull fracture
- sign of basal skull fracture
- post traumatic seizure
- focal neurology
- vomited more than once since head injury
CT within 8 hours of injury if:
- currently on warfarin
- LOC/amnesia + one of:
- age >65
- history of bleeding or clotting disorder
- dangerous mechanism
- more than 30 mins retrograde amnesia prior event
If the following are affected what's the syndrome? Medial lemniscus Red nucleus Oculomotor nerve fibres Oculomotor nerve
Paramedian midbrain syndrome (Benedikt syndrome)
If the following are affected what’s the syndrome?
- ipsilateral oculomotor nerve palsy with a drooping eyelid and fixed wide pupil pointed down and out. This leads to diplopia (oculomotor nerve fibers)
- difficulty with contralateral lower facial muscles and hypoglossal nerve functions (corticobulbar tract)
- contralateral hemiparesis and typical upper motor neuron findings. It is contralateral because it occurs before the decussation in the medulla. (corticospinal fibers)
- contralateral parkinsonism because its dopaminergic projections to the basal ganglia innervate the ipsilateral hemisphere motor field, leading to a movement disorder of the contralateral body (substantia nigra)
Medial midbrain syndrome (Weber syndrome), occlusion of the paramedian branches of the posterior cerebral artery
If the following are affected what’s the syndrome?
- Contralateral loss of pain and temperature from the trunk and extremities (Lateral spinothalamic tract)
- (1) Ipsilateral paralysis of the upper and lower face (lower motor neuron lesion).
- (2) Ipsilateral loss of lacrimation and reduced salivation.
- (3) Ipsilateral loss of taste from the anterior two-thirds of the tongue.
- (4) Loss of corneal reflex (efferent limb). (Facial nucleus & facial Nerve (CN.VII))
- Ipsilateral loss of pain and temperature sensation from the face (facial hemianesthesia) (Spinal trigeminal nucleus and tract)
- Nystagmus, nausea, vomiting, and vertigo (Vestibular Nuclei and intraaxial nerve fibers)
- Hearing loss - ipsilateral central deafness (Cochlear nuclei and intraaxial nerve fibers)
- Ipsilateral limb and gait ataxia (Middle & inferior cerebellar peduncle)
- Ipsilateral Horner’s syndrome (ptosis, miosis, & anhydrosis) (Descending sympathetic tract)
Lateral pontine syndrome (AICA)
If the following are affected what’s the syndrome?
- Contralateral spastic hemiparesis (Corticospinal tract)
- Contralateral DCML pathway loss (tactile, vibration, and stereognosis) (Medial lemniscus)
- Strabismus (ipsilateral lateral rectus muscle paralysis - the affected eye looks down and towards the nose). Abducens nerve lesion localizes the lesion to inferior pons.
Medial pontine syndrome (medial basilar infarct)
If the following are affected what’s the syndrome?
- Dysphagia, hoarseness, absent gag reflex (efferent limb - CN.X)
- Dizziness, nausea, and vomiting (Vestibular nuclei)
Nystagmus (Vestibular nuclei)
- Ipsilateral cerebellar signs including ataxia, dysmetria (past pointing), dysdiadochokinesia (Cerebellar peduncle)
- Contralateral deficits in pain and temperature sensation from body (limbs and torso) (Lateral spinothalamic tract)
- Uncontrollable hiccups
- Ipsilateral deficits in pain and temperature sensation from face (Spinal trigeminal nucleus & tract)
- Loss of taste on one side of the tongue
- Decreased sweating (Descending sympathetic fibers)
- Changes in heart rate and blood pressure
Lateral medullary syndrome (PICA syndrome, Wallenberg syndrome)
If the following are affected what’s the syndrome?
- a deviation of the tongue to the side of the infarct on attempted protrusion, caused by ipsilateral muscle weakness of hypoglossal nerve fibers
- limb weakness (or hemiplegia, depending on severity), on the contralateral side of the infarct (medullary pyramid and hence to the corticospinal fibers of the pyramidal tract)
- a loss of discriminative touch, conscious proprioception, and vibration sense on the contralateral side of the infarct (medial leminiscus)
Medial medullary syndrome
Which hemisphere are Broca’s and Wernicke’s are found?
Dominant hemisphere
What are the causes of peripheral polyneuropathy?
Toxic (Chemorx, amiodorone, alcohol)
Inflammatory (GBS, CIDP, paraprotein, MFMN)
Infective (diptheria, leprosy, lyme)
Inherited (CMT)
Metabolic (DM, B12, uraemic)
Paraneoplastic
What is CIDP?
Chronic inflammatory demyelinating polyneuropathy
What is MFMN?
Multifocal motor neuropathy
What’s the condition?
Progression of symptoms over days to 4 weeks, legs weaker than arms and symmetrical, mild sensory symptoms or signs, bilateral weakness of facial muscles, more common in males
Guillain Barre Syndrome
What investigations would help confirm GBS?
LP: elevated CSF, fewer than 10 cells
EMG/NCV: conduction block, increased distal latency
What’s normally affected in MG?
Extra ocular muscles (65%) Bulbar muscles (10%) Limb muscles (leg 10%) Respiratory muscles (1%)
What are the small fiber sensations?
Pain
Temperature
What are the large fiber sensations?
Proprioception
Vibration
Light touch
What can cause a single episode of vertigo?
Vestibular neuritis Systemic illness TIA Otitis media Syphilis
If you were describing a CT scan would you use density or intensity?
Density
What are common UMN conditions?
Stroke
MS (demyelinaton)
Head injury
Cerebral palsy
What are common LMN conditions?
Entrapment neuropathies
Guillain-Barré
Diabetes
Alcohol
Which nerves can be affected by a cerebellopontine angle tumour?
V, VI, VII, VIII
Differentials for ptosis
– III nerve palsy
– Horner’s syndrome/ internal carotid artery dissection
– myasthenia gravis
What are the key features of parkinson’s disease?
Tremor
Rigidity
Bradykinesia
What things are done as part of the cerebellar exam?
• Ipsilateral • Heel-toe walking • Nystagmus • Speech e.g. Britsh Constituton • Finger-nose test • Dysdiadochokinesis the abnormality, not the test name • (Heel-shin test) • (Broad-based gait)
Abnormal speech can be due to what?
Dysphasia
Dysarthria (cerebellum, CNIX, X, XII)
What are the features of Brown-Sequard?
Motor loss ipsilateral
Pin-prick loss contralateral
What are the features of a syringomyelia?
Differential sensory loss- spares dorsal columns
UL LMN signs
LL UMN signs
Which tuning fork would you use to test vibration?
128 Hz
What tasks would someone with proprioception loss find particularly hard?
Washing face
Taking off a jumper
What are the cognitive domains?
Memory Language Executive function/behaviour Perception/attention Praxis Attention
A lesion in which region would cause dysphasia, impaired speech context with fluency and normal comprehension?
Arcuate fasciculus
Memory for facts is known as?
Semantic memory
Memory for events is known as?
Episodic memory
What are the categories of declarative memory?
Episodic
Semantic
What are the categories of non-declarative memory?
Procedural (e.g riding a bike)
Conditioning
What structure is important for integrating new memories?
Hippocampus
Which conditions can affect memory?
Alzheimer’s disease
Korsakoff’s syndrome (B1 deficiency, alcohol abuse, post bariatric surgery)
Limbic encephalitis
Transient amnesic syndromes
What would you see post mortem in Alzehimer’s disease?
- Extracellular amyloid plaques
- Intraneuronal neurofibrillary tangles
What can cause limbic encephalitis?
- Infections (HSV)
- paraneoplastic
- Nonparaneoplastic (VGKC) ab
What are the features of transient global amnesia?
- onset age 45-75
- 4-12 hours amnesia
- self limiting
- commonly presents to A&E
What’s being described?
Impaired speech comprehension with preserved speech fluency
Wernicke’s aphasia
What are the features of frontotemporal dementia?
- aka Pick’s disease
- younger onset than Alzheimers
- behaviour deterioration
- frontal lobe atrophy
- lack of insight
What are the features of posterior cortical atrophy?
- visuospatial and visuoperceptual capabilities decreased
- visual problems (difficulty reading, blurred vision, light sensitivity)
- issues with depth perception
- trouble navigating through space
- apraxia
- alexia (impaired reading)
- visual agnosia (object recognition disorder)
- anxiety
- depression
Where is the ‘what stream’ and what does damage in this area cause?
Temporal lobe, leads to the symptoms related to general vision and object recognition deficits
Where is the ‘where/how stream’ and what does damage in this area cause?
Damage to the dorsal, or “where/how” stream, located in the parietal lobe, leads to PCA symptoms related to impaired movements in response to visual stimuli, such as navigation and apraxia.
What’s prosopagnosia?
Inability to recognize faces.
Acquired prosopagnosia results from occipito-temporal lobe damage and is most often found in adults.
What is praxis?
Plan and execute a movement. Test by getting them to copy hand movements
What spinal cord level does the arachnoid layer end?
S2
What is damaged in a subdural haematoma?
superior cerebral (bridging) veins
What causes subarachnoid haemorrhages?
70% saccular ‘berry’ aneurysms
10% Arteriovenous malformations
20% not defined
What forms the coccygeal ligament?
The caudal termination of the dural sac invests the filum terminale to
form the coccygeal ligament.
What is the filum terminale interna made of?
Pia
What is the filum terminale externa made of?
Dura and pia
What’s the condition?
Proptosis, chemosis (swelling of the conjunctiva) and
painful ophthalmoplegia
Cavernous sinus thrombosis
In a right handed person what are the functions of the left hemisphere?
- Analytical and logical thinking
- Language (except emotional prosody)
- Expression of emotion
In a right handed person what are the functions of the right hemisphere?
- Spatial abilities
- Comprehension of complicated patterns drawings
- Perceiving emotion
Which area of the brain is important for decision making and self control?
Ventro medial Prefrontal cortex
Lesions of S1 result in impairment of what?
– Two-point discrimination – Localization of touch – Position sense – Stereognosis – Graphesthesia
Lesions in the right parietal cortex in a right handed person causes what?
– Disturbances in integration of personal and extrapersonal space
– Hemispatial neglect
– Constructional apraxia
– Dressing apraxia
Lesions in the left parietal cortex in a right handed person causes what?
– Disorders of language – Gerstmann Syndrome (AG) • Right-Left Disorientation • Acalculia • Agraphia • Finger agnosia
What’s the function of the insular lobe?
•Receives visceral, taste, and pain sensory information
What causes macular sparing?
- Dual vascular supply -branches of both the middle and posterior cerebral arteries
- Extensive cortical representation of the central visual field
What are the risk factors for lipohyalinosis?
- Age
- HTN / chol
- DM
- Smoking
What are the possible signs of a lacunar stroke?
- Pure Motor
- Pure Sensory
- Sensorimotor
- Ataxic hemiparesis
What are the features of cerebellar syndrome?
Dysdiadochokinesia Ataxia Nystagmus Intention tremor Slurred, staccato speech Hypotonia/heel-shin test Past pointing
What’s the term for a dilated pupil?
Mydriasis
What’s a medical third nerve palsy?
pupil is spared so just lid closure and down and out pupil
What are the causes of a third nerve palsy?
- diabetes
- MS
- cavernous sinus thrombosis
- amyloid
- posterior communicating artery aneurysm (usually painful)
- tumour
- Webers syndrome: ipsilateral third nerve palsy with contralateral hemiplegia = midbrain stroke
How would someone with a 4th nerve palsy present?
Diplopia - particularly marked in reading abnormal head posture - head tilted towards the normal side, face rotated towards the normal side, and the chin is depressed.
The affected eye is higher than its fellow.
What’s the name of the squint that is caused by a lateral rectus palsy?
Convergent squint/ medial strabismus/ esotropia
When is double vision at its worst with a paralytic lateral rectus muscle?
when looking toward the paretic lateral rectus muscle
Where is the trigeminal ganglion?
occupies a cavity (Meckel’s cave) in the dura mater, covering the trigeminal impression near the apex of the petrous part of the temporal bone
What’s the function of the lateral corticospinal tracts?
Main tract for voluntary motor (upper extremity motor pathways are more central)
Which tracts carry sensory information?
Dorsal columns
- light touch
- vibration
- proprioception
Lateral spinothalamic
- pain
- temperature
Ventral spinothalamic tract
- crude touch
- pressure
What can cause Brown-Sequard syndrome?
- most commonly trauma (penetrating or blunt)
- neoplasia
- MS
- degenerative (herniation of discs or cervical spondylosis)
- cysts
- vascular (spinal subdural/epidural and haematomyelia)
- ischaemia
- infection (meningitis, empyema, herpes zoster, herpes simples, TB, syphilis)
What’s the condition?
Paraplegia, loss of sensation below the lesion, urinary retention, faecal incontinence
Complete transverse sensorimotor myelopathy
What’s the condition?
Sensory and motor peripheral neuropathy involving isolated damage to at least 2 separate nerve areas. Painful and asymmetrical
Mononeuropathy multiplex
Which arteries does the 3rd nerve pass between?
PCA and superior cerebellar artery
How do the vertebral arteries enter the cranium?
Through the foramen magnum
What is hydrocephalus?
abnormal accumulation of cerebrospinal fluid (CSF) within the ventricles and/or subarachnoid space of the brain.
What are the causes of hydrocephalus?
- Overproduction of CSF
- Ventricular Obstruction
- Obstructed arachnoid granules
- Venous thrombosis
Which drugs can cause peripheral neuropathy?
- metronidazole
- isoniazid
- vincristine
- amiodarone
- nitrofurantoin
How do you manage migraines?
It should be noted that as a general rule 5-HT receptor agonists are used in the acute treatment of migraine whilst 5-HT receptor antagonists are used in prophylaxis. NICE produced guidelines in 2012 on the management of headache, including migraines.
Acute treatment
- first-line: offer combination therapy with an oral triptan and an NSAID, or an oral triptan and paracetamol
- for young people aged 12-17 years consider a nasal triptan in preference to an oral triptan
- if the above measures are not effective or not tolerated offer a non-oral preparation of metoclopramide* or prochlorperazine and consider adding a non-oral NSAID or triptan
Prophylaxis
- prophylaxis should be given if patients are experiencing 2 or more attacks per month. Modern treatment is effective in about 60% of patients.
- NICE advise either topiramate or propranolol ‘according to the person’s preference, comorbidities and risk of adverse events’. Propranolol should be used in preference to topiramate in women of child bearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives
- if these measures fail NICE recommend ‘a course of up to 10 sessions of acupuncture over 5-8 weeks’ or gabapentin
- NICE recommend: ‘Advise people with migraine that riboflavin (400 mg once a day) may be effective in reducing migraine frequency and intensity for some people’
- for women with predictable menstrual migraine treatment NICE recommend either frovatriptan (2.5 mg twice a day) or zolmitriptan (2.5 mg twice or three times a day) as a type of ‘mini-prophylaxis’
- pizotifen is no longer recommend. Adverse effects such as weight gain & drowsiness are common
*caution should be exercised with young patients as acute dystonic reactions may develop
What area is affected in Wernicke and Korsakoff syndrome?
Medial thalamus and mammillary bodies of the hypothalamus
What area is affected in Hemiballism?
Subthalamic nucleus of the basal ganglia
What area is affected in Huntington chorea?
Striatum (caudate nucleus) of the basal ganglia
What area is affected in Parkinson’s disease?
Substantia nigra pars compacta of the basal ganglia
What area is affected in Kluver-Bucy syndrome?
Amygdala
What are the features of Kluver Bucy syndrome?
hypersexuality, hyperorality, hyperphagia, visual agnosia
Which tracts and clinical manifestations are seen in Subacute combined degeneration of the spinal cord (vitamin B12 & E deficiency)?
- Lateral corticospinal tracts (Bilateral spastic paresis)
- Dorsal columns (Bilateral loss of proprioception and vibration sensation)
- Spinocerebellar tracts (Bilateral limb ataxia)
What are the features of a cluster headache?
- Pain typical occurs once or twice a day, each episode lasting 15 mins - 2 hours with clusters typically lasting 4-12 weeks
- Intense pain around one eye (recurrent attacks ‘always’ affect same side)
- Patient is restless during an attack
- Accompanied by redness, lacrimation, lid swelling
- More common in men and smokers
What are the features of a migraine?
- Recurrent, severe headache which is usually unilateral and throbbing in nature
- May be be associated with aura, nausea and photosensitivity
- Aggravated by, or causes avoidance of, routine activities of daily living. Patients often describe ‘going to bed’.
- In women may be associated with menstruation
What are the features of a tension headache?
- Recurrent, non-disabling, bilateral headache, often described as a ‘tight-band’
- Not aggravated by routine activities of daily living
What are the features of medication over use headache?
- Present for 15 days or more per month
- Developed or worsened whilst taking regular symptomatic medication
- Patients using opioids and triptans are at most risk
- May be psychiatric co-morbidity
What are the differentials for acute, one-off headache?
- meningitis
- encephalitis
- subarachnoid haemorrhage
- head injury
- sinusitis
- glaucoma (acute closed-angle)
- tropical illness e.g. Malaria
When are triptans contraindicated?
patients with a history of, or significant risk factors for, ischaemic heart disease or cerebrovascular disease
What is the first-line treatment for myoclonic seizures?
Sodium valproate
What are the 6 components of language?
- production (speech)
- comprehension
- repetition
- writing
- reading
- naming
What’s the ABCD2 score? When is it used?
Risk stratification of TIA
A: Age
>= 60 years, 1 point
B: Blood pressure
BP >= 140/90 mmHg, 1 point
C: Clinical features
Unilateral weakness, 2 points
Speech disturbance without weakness, 1 point
D1: Duration of symptoms
>= 60 minutes, 2 points
10-60 minutes, 1 point
<10 minutes, 0 point
D2: Diabetes
Diabetic
1 point
What’s a vegetative state?
- rousable
- severe bilateral hemisphere damage
- no awareness of themselves or environment
- eyes can open/close spontaneously
- can get spontaneous movements of face, trunk and limbs
- no communication
- less than 6 months
What are the features of brain death?
- require ventilation
- no reflexes
Minimally conscious state
patients with MCS have partial preservation of conscious awareness
