Neurology Flashcards
(345 cards)
Diastematomyelia
Spinal malformation where the spinal cord is split by bony/fibrous structure, resulting in symptoms of a tethered cord (limb weakness, back pain, scoliosis).
Often associated with vertebral anomalies
Dandy-Walker malformation
Brain malformation with hypoplasia of the cerebellum (esp vermis), with often marked enlargement of the posterior fossa. Present usually in the first year of life with hydrocephalus, “sun downing”, irritability and sleepiness
Meningocele
Meninges herniate through a defect in the posterior vertebral arches, usually normal spinal cord (but may be associated with syntax or riastematomyelia)
Myelomeningocele
Both the meninges and the spinal cord herniate through the spine, often resulting in weakness of the lower extremes and bladder/bowel dysfunction
Causes of Horner syndrome
Primary neuron lesion
Brainstem stroke/tumour
Trauma to the brachial plexus
Tumour/infection of lung apex
Postganglionic neuron lesion
Dissecting carotid aneurysm
Carotid artery ischeamia
Migraine
Middle cranial fossa neoplasm
Basis of triplet repeat studies?
Some genes have inherently unstable triplet repeat regions, with the number of repeats varying in mitosis and meiosis, if the number of repeats reaches a critical level it becomes methylated and therefore inactivated, resulting in phenotypic abnormalitis
Examples of triplet repeat expansion disorders?
Fragile X syndrome
Myotonic dystrophy
Huntington disease
Spinocerebellar ataxias
(caused by expansion in the number of 3-bp repeats)
High risk of latex allergy associated with which condition?
Spina bifida - allergy to latex products due to repeated exposures (e.g. frequent surgery e.g. abdo/genitourinary, IDCs, VP shunts)
Patients are sensitised through direct mucosal exposure to products from multiple surgeries early in life
Extensor plantar responses with absent lower limb deep tendon reflexes?
Friedrich’s ataxia
- also can have cerebellar signs
Methotrexate-related leukoencephalopathy
Presents as non-specific neurological dysfunction - seizures, encephalopathy, word finding difficulties, ataxia, weakness, blurred vision
Risk factors include high cumulative dose, IT methotrexate and prolonged methotrexate clearing times
MRI brain findings with methotrexate-related leukoencephalopathy
White matter changes (particularly in the centrum semiovale) which are usually reversible
Causes of posterior reversible encephalopathy syndrome (PRES)?
Medications - cyclosporin, tacrolimus, interferon, erythropoietin
Hypertension
Features of Panayiotopoulos syndrome
Usually nocturnal and prolonged seizures (more than 5 minutes, 50% last more than 30 minutes), with ictal vomiting the most characteristic sign.
Variant of benign childhood epilepsy with occipital spikes
Charcot-Marie-Tooth: effects on tone and reflexes?
Tone normal, reflexes absent
Unilateral equinovarus and diurnal variation in gait are classical presenting features of which disease?
Segawa disease (dopa-responsive dystonia)
Classically present with unilateral equinovarus, and diurnal variation (typically toe walking which worsens throughout the day)
Gait abnormalities in autism?
Toe walking, with normal neurological examination
Prolonged febrile seizures should raise concern for?
Dravet syndrome/SCN1A channelopathy
What are the typical seizures associated with Dravet syndrome?
Hemiclonic seizures and vaccine proximal seizures
EEG changes in Dravet syndrome in children >12 months?
Normal EEG in first 12 months usually
Antiepileptics most useful in Dravet?
Sodium valproate, topiramate, stiripentol
- caution with phenytoin (may exacerbate seizures)
Frequency of positive genetic testing in Dravet syndrome?
80%
EEG: large amplitude spikes or sharp waves maximal over centrotemporal region
Benign epilepsy with centrotemporal spikes (benign rolandic epilepsy)
EEG: frequent triphasic wave pattern
Hepatic encephalopathy
EEG: low voltage pattern evolving to seizure activity
Stage 2 HIE