general neuro Flashcards
(349 cards)
what lobe?
seizure
Hallucinations (auditory/gustatory/olfactory), Epigastric rising/Emotional, Automatisms (lip smacking/grabbing/plucking), Deja vu/Dysphasia post-ictal)
Temporal lobe (HEAD)
What lobe seizure?
Head/leg movements, posturing, post-ictal weakness, Jacksonian march
Frontal lobe (motor)
what lobe seizure?
paraesthesia
Parietal lobe (sensory)
what lobe seizure?
floaters/flashes
Occipital lobe (visual)
Brain scan where does encephalitis classically affect
temporal lobe
Hypsarrhythmia on EEG
Infantile spasms (west’s syndrome)
What birth defects are sodium valproate associated with
neural tube defects
hypospadias most common
epilepsy management pregnancy
aim for mono therapy
lamotrigine is often best choice
5mg folic acid prior to getting pregnant if possible
Normal lumbar puncture result
clear appearance
glucose 70% of plasma
protein 0.3 g/l
WCC 2 per mm^3 (neuts)
Bacterial meningitis LP result
Cloudy
Glucose low (< 1/2 plasma) bacteria using up the glucose
Protein high (> 1 g/l) bacteria releasing proteins
WCC 10 - 5,000 polymorphs/mm³ the immune system releases neutrophils in response to bacteria
Viral meningitis LP result
Clear/cloudy
Glucose 60-80% of plasma glucose* viruses don’t really use glucose
Protein normal/raised viruses may release a small amount of protein
WCC 15 - 1,000 lymphocytes/mm³ the immune system releases lymphocytes in response to viruses
Tuberculous LP result
Slight cloudy, fibrin web
glucose Low (< 1/2 plasma)
Protein high >1g/l
WCC 30-300 lymphocytes/mm3
The Ziehl-Neelsen stain is only 20% sensitive in the detection of tuberculous meningitis and therefore PCR is sometimes used (sensitivity = 75%)
Management of brain abscess?
surgery - craniotomy
IV antibiotics: IV 3rd-generation cephalosporin + metronidazole
intracranial pressure management: e.g. dexamethasone
EEG : 3Hz generalized, symmetrical
absence seizures
EEG centro-temporal spikes
Benign rolandic epilepsy
Contraindications to lumbar puncture
focal neurological signs
papilloedema
significant bulging of the fontanelle
disseminated intravascular coagulation
signs of cerebral herniation
For patients with meningococcal septicaemia a lumbar puncture is contraindicated - blood cultures and PCR for meningococcus should be obtained.
Degenerative cervical myelopathy
Presentation: myelopathy: pain (affecting the neck, upper or lower limbs) loss of fine motor function (dexterity, clumsy) loss of sensory function causing numbness, loss of autonomic function, hoffmans
Causes: Cervical spondylosis (osteophyte), disc herniation
Investigation: MRI
Management: decompressive surgery
Neoplastic spinal cord compression
Presentation: cancer patient, back pain, bilateral weakness, UMN signs. First symptom: back pain
Investigation: MRI of whole spine
Management: high dose dexamethasone and oncology assessment
Brown-sequard syndrome
- ipsilateral dorsal column signs
- ipsilateral corticospinal tract signs
- contralateral spinothalamic tract signs
Subacute combined degeneration of spinal cord
Presentation: bilateral dorsal column signs, may have bilateral corticospinal tract signs (affects posterior cord)
Cause: B12 deficiency
Prevention: Always replace vitamin B12 before folate - giving folate to a patient deficient in B12 can precipitate subacute combined degeneration of the cord
Friedrich’s ataxia
Presentation: teenage corticospinal, spinocerebellar, dorsal column and peripheral nerves
Information: autosomal recessive trinucleotide repeat disorder resulting in reduced level or function of the frataxin protein.
Investigation: genetic analysis
Management: supportive
Syringomyelia
Pathophysiology: development of a fluid-filled cyst (a syrinx) around the spinal canal.
Causes: Chiari malformation, tumour, trauma
Presentation: ‘central cord syndrome’ bilateral spinothalamic and/or bilateral corticospinal tract symptoms. The upper limbs are affected first whilst the lower limbs are spared until much later. As the fibres of the spinothalamic tract enter the spinal cord and immediately decussate, they pass close to the spinal canal, meaning they are often the first of these white matter fibres to be compressed and damaged. As the cervical cord is the most likely location of the lesion, there is classically said to be a “cape-like” loss of pain and temperature sensation.
Investigation: full spine MRI with contrast and brain MRI
Management: treat cause. If persistent : shunt
Lumbar spinal stenosis
Presentation: back pain, bilateral leg weakness or unilateral, positional element: better on walking up hill and sitting forward. Ddx claudication
Investigation: MRI
Management: Laminectomy
Ankylosing spondylitis
Presentation: young man, lower back pain and stiffness, worse in morning
Investigation: plain x ray of sacroiliac joints
Management: encourage regular exercise such as swimming, NSAIDs are the first-line treatment, physiotherapy