Neurology -6.02 Spina Bifida And Epilepsy

Front 1

Define: Seizure

Back 1

An uncontrolled discharge of nerve cells which may spread to other nearby cells or throughout the entire brain

Front 2

How long does a seizure last

Back 2

usually only a few minutes at most

Front 3

Define: Epilepsy

Back 3

A disorder of the brain that results in recurrent unprovoked seizures that has occurred >2 times on >1 occasion

Front 4

True of False

Epilepsy's prevalence is not dependent on geographical, racial and social, thus third world and first world incidences are approximately equal

Back 4

False

There is a higher incidence rate in developing countries because they are at higher risk of diseases which can lead to permanent brain damage

Front 5

List some risk factors for epilepsy

Back 5

Stroke
Head injury
Infection
Brain tumour
Birth trauma
Malformations of the brain
CNS infection

Front 6

What are the classifications of epilepsy?

Back 6

1. Generalised seizure
2. Partial (focal) seizure
3. Simple seizure
4. Complex seizure

Front 7

What is the difference between simple and complex seizures?

Back 7

Simple: without lost of consciousness
Complex: with loss of awareness of the attack

Front 8

What is the term for focal EED changes which spreads to generate activity on both hemispheres called?

Back 8

Partial seizure with secondary generalisation

Front 9

List some triggers for seizures

Back 9

1. Sleep deprivation
2. Alcohol
3. Recreational drug use
4. Physical/mental exhaustion
5. Flickering lights
6. Infections and metabolic disturbances
7. Low blood glucose

Front 10

Describe what happens to a patient in a tonic clonic (grand mal) seizure

Back 10

1. Aura
2. Rigidity + unconsciousness
3. Respiration arrested
4. Clonic jerks (some may have flaccid coma instead)
5. Conscious but confused for >30mins with loss of memory

Front 11

Describe what happens to a patient in an absence seizure (petit mal)

Back 11

There is loss of awareness (resembling a complex partial seizure)

Duration is short: 20-30secs, however more frequent

Not associated with post ictal confusion and no loss of posture

Front 12

If a patient has a history of epilepsy and has a brief loss of muscle tone (heavy fall) what seizure did the patient experience?

Back 12

Atonic Seizure

Front 13

If a patient has collapsed in what seems to be an atonic seizure without having a history of epilepsy, would you still consider what the patient experienced to be an atonic seizure?

Back 13

No

Only occurs in the context of epilepsy syndromes and should not be considered in Ddx of collapse without epileptic Hx.

Front 14

What is the conscious state of a person experiencing an atonic seizure?

Back 14

May/may not experience loss of conciousness

Front 15

What is the expected conscious state of person experiencing a simple partial seizure?

Back 15

Conscious

Front 16

Is a simple partial a focal or generalised seizure? And where would it affect?

Back 16

Focal seizure
Can affect: motor, sensory, ANS and psychic

Front 17

Describe the features of a complex partial seziure

Back 17

1. de ja-vu: alteration of memory, hallucination of smell, taste, etc
2. Altered consciousness but does not fall
3. Stares blankly
4. Automatism e.g. lip smacking
5. Duration: few minutes
6. After: muddled & drowsy

Front 18

What are the indications for brain imaging?

Back 18

1. Epilepsy starting >20 years
2. Seizures have focal clinical features
3. EEG shows focal seizure source
4. Control of seizure is difficult or deteriorates

Front 19

True of false:

EGG findings can support a diagnosis of epilepsy and often contribute to the correct classification

Back 19

True

EEGs are central to current classification of epilepsy syndrome

Front 20

What are the drugs used to treat epilepsy?

Back 20

1. Carbamazepine
2. Phenytoin
3. Benzodiasepine
4. Barbiturates (dangerous)
5. Sodium valproate

Front 21

What is the action of Carbamazepine?

Back 21

Inhibits Na channels of axons of both inhibitory and excitatory neurones = global depression (Limits frequency of nerve implies conduction)

Also able to inhibit the release of glutamate via partially agonising adenosine receptors

Front 22

What is the action of phenytoin?

Back 22

Global depression through inhibition of Na channels along the axon

Front 23

What is the action of Benzodiazepine (Diazepam)

Back 23

Increase frequency of GABAa receptor channel opening

Front 24

What is the action of barbiturates?

Back 24

Same as benzodiazepine...

Front 25

What is the action of sodium valproate?

Back 25

Inhibits GABA metabolism in the synaptic cleft

Front 26

What is one problem with the drug treatment of epilepsy?

Back 26

Narrow therapeutic range

Front 27

True or false

You don't need to monitor drug levels in epilepsy treatment because they titrate unpredictably due to saturation of liver metabolising enzymes

Back 27

False

You can monitor serum drug levels for Carbamazepine, Phenytoin and Sodium valproate.

However, it is true that you can't monitor all.

And Phenytoin does titrate unpredictably.

Front 28

What is the significance of TDM (therapeutic drug monitoring) for epileptic drugs during pregnancy?

Back 28

Metabolism of phenytoin and carbamazepine increases

Front 29

What is the first line drug for epilepsy due to a partial seizure?

Back 29

Carbamazepine

Front 30

What is the first line drug for primary GTCS (generalised tonic clonic seizures)

Back 30

Sodium Valproate

Front 31

What is the 1st line drug treatment for epilepsy with absence seizure?

Back 31

Ethosuximide

Front 32

What is the 1st line drug treatment for epilepsy with myoclonic seizure?

Back 32

Sodium Valporate

Front 33

What is the 1st line drug treatment for epilepsy with secondary GTCS?

Back 33

Carbamazpine

Front 34

What are the features which would help you diagnose syncope?

Back 34

Precipitating factors
Light-headed
Limp fall
Brief
Rapid recovery
No incontinence or tongue bite
Normal EEG

Front 35

Name another drug used to treat epilepsy, besides from Carbamazepine that is able to block axonal conduction of nerve impulses

Back 35

Phenobaritone

Front 36

What is the usefulness of EEG on a single seizure patient when you want to diagnose epilepsy?

Back 36

Good specificity but poor sensitivity in diagnosis of epilepsy

Front 37

What is the value of EEG for a patient with a single seizure in determine the risk of recurrence?

Back 37

No value

Front 38

What is the value of EEG for a patient with a single seizure when giving advice for treatment?

Back 38

No value

Front 39

What is the usefulness of an MRI in determining the risk of recurrence after a single seizure?

Back 39

Useful as finding a focal pathology in an MRI increases the risk of seizure recurrence

Front 40

In a single seizure with focal patterns, how useful is the MRI?

Back 40

Important as it can be use to locate focal pathologies

Front 41

What is the usefulness of EEG when used on a patient with recurrent seizures?

Back 41

Interictal EEGs are useful as it can show epileptiform abnormalities which can diagnosis epilepsy and along with clinical features EEGs help to classify the epilepsy

Front 42

Describe the epidemiology of Spina Bifida

Back 42

Occulta = 10% of the population
Meningocele = 1/50,000
Myelomeningocele =1/2,000

Front 43

Define Spina Bifida

Back 43

Neural tube defect
Failure of the VC to fuse
SC may protrude

Front 44

List the Rx factors of neural tube defects in general

Back 44

1. Diabetes
2. Folic acid deficiency
3. Antiepileptic drugs
4. Iodine deficiency
5. Rubella
6. Radiation
7. Anticancer drugs

Front 45

List the general features of spinal defects

Back 45

Various degrees of
Limb weakness
Sensory loss
Urinary disorders
Hydrocephalus

Front 46

List specific features related to patients with meningomyelocele

Back 46

70-90% of children are born with hydrocephalus
90% will develop urinary problems
1/3 have complete paralysis and loss of sensation below the defect level
1/3 have preservation of distal segments below defect level
1/3 have an incomplete lesion

Front 47

How would you defect spina bifida in a pregnant mother?

Back 47

increase levels of serum alpha-fetoprotein

suggestive of neural tube defect and will need further investigation

Front 48

How accurate is the test for spina bifida?

Back 48

The test isn't specific for spina bifida, but it suggests neural tube defect

Front 49

What errors can confound the results of serum alpha-fetoprotein?

Back 49

1. error in the date of conception
2. >1 baby
3. other birth defects

Front 50

What on-going imaging studies would you do for the child after birth and as the child grow up?

Back 50

1. Plain radiographs -clinical evaluation for scoliosis, dysplasia and hip dislocation
2. Ultrasound and radiographs -assess areas of pain b/c of high Rx of pathologic fractures
3. Computer tomography scan -

Front 51

List the general features of spinal defects

Back 51

Various degrees of
Limb weakness
Sensory loss
Urinary disorders
Hydrocephalus

Front 52

List specific features related to patients with meningomyelocele

Back 52

70-90% of children are born with hydrocephalus
90% will develop urinary problems
1/3 have complete paralysis and loss of sensation below the defect level
1/3 have preservation of distal segments below defect level
1/3 have an incomplete lesion

Front 53

How would you defect spina bifida in a pregnant mother?

Back 53

increase levels of serum alpha-fetoprotein

suggestive of neural tube defect and will need further investigation

Front 54

How accurate is the test for spina bifida?

Back 54

The test isn't specific for spina bifida, but it suggests neural tube defect

Front 55

What errors can confound the results of serum alpha-fetoprotein?

Back 55

1. error in the date of conception
2. >1 baby
3. other birth defects

Front 56

What on-going imaging studies would you do for the child after birth and as the child grow up?

Back 56

1. Plain radiographs -clinical evaluation for scoliosis, dysplasia and hip dislocation
2. Ultrasound and radiographs -assess areas of pain b/c of high Rx of pathologic fractures
3. Computer tomography scan - evaluate recurrence of hydrocephalus or changes in ventricles
4. MRI -information about the SC and malformations

Front 57

At what gestational week would a problem have to occur in order to result in SB occult occur?

Back 57

5-12 weeks

problem with somite/mesoderm

Front 58

At what gestation week would a problem have to occur in order to result in SB meningocele cystica?

Back 58

5-12

problem with somite/mesoderm

Front 59

AT what gestational week would a problem have to occur in order to result in SB myeloeminigocele cystica?

Back 59

2-4 weeks

problem with neural tube closure i.e. migration of somites

Front 60

What are the treatments/managements for SB myeloeminigocele cystica?

Back 60

1. Surgical management of cyst
2. Treat hydrocephalus via ventriculoperitoneal shut

Front 61

How would you recommend prevention of neural tube defect?

Back 61

Adequate folate intake (supplements) before and during early pregnancy.