PHM142 Fall 2012 Instructor: Dr. Jeffrey Henderson. Pediatric Epilepsy. Ashley Masse Arif Mohamed Rosalie Nguyen Yusuf Majumder. What is Epilepsy?. Epilepsy is a neurological disorder change in normal brain function. Epilepsy is not generally an inherited disease.
Epilepsy is a neurological disorder change in normal brain function.
Epilepsy is not generally an inherited disease.
Typically characterized by seizures.
About 0.6% of the Canadian population has Epilepsy.
There are two major types of epilepsy
Idiopathic Epilepsy- no known cause
Secondary/Somatic Epilepsy- the cause is attributed to a specific event (such as genetic conditions, hitting ones head, or stroke).
Epilepsy is further classified by the type of seizure the person experiences.
Types include: generalized tonic-clonic, absence, myoclonic, and partial.
About 50% of children “grow out” of the disorder and experience a complete disappearance of seizures.
Some of those who continue to have seizures into adulthood often notice a decrease in intensity and frequency.
* Slow component:
* Rapid component:
- Additional rapid and sharp depolarizations.
-The extracellular potassium level is increased, and thus it is more difficult for potassium to leave the cell.
-The net current will be inward leading to depolarization that will occur to the extent that calcium currents will “be triggered”, so more neurotransmitter released.
- Activation of NMDA receptors by glutamate.
- Inactivation of the inward current.
- Activation of the potassium outward current.
- Increase in chloride current into the cell.
Changes in diet
Surgery: for refractory (intractable) epilepsy
Corpus callosotomy: sectioning of the corpus callosum to prevent and block spread of epileptic discharges interhemispherically
Can be partial or complete
Ketogenic diet: high fat, low carbohydrate diet
Used to treat difficult-to-control, intractable epilespy
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Epilepsy Canada. (2012). Living with Epilepsy, Facts, Epidemiology, & Diagnosis and Treatment. In Epilepsy Canada. Retrieved November 25, 2012, from www.epilepsy.ca.
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Badawy, R. A. B., Harvey, A. S., & Macdonell, R. A. L. (2009). Cortical hyperexcitability and epileptogenesis: Understanding the mechanisms of epilepsy - part 2. Journal of Clinical Neuroscience, 16(4), 485-500. Retrieved from www.scopus.com
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Blume W. T. (2003). Diagnosis and management of epilepsy. CMAJ, 168: 441-448
Canadian Pharmacists Association. (2012). , Seizures and Epilepsy, Therapeutic Choices. (pp 292-301) Webcom, Toronto, ON.
Deivasumathy Muthugovindan, and Adam L. Hartman. (2010). Pediatric Epilepsy Syndromes. The Neurologist, 16: 223-237.
David R. Fish, Shelagh J. Smith, Luis F. Quesney, Frederick Andermann, Theodore Rasmussen ( 2005). Surgical Treatment of Children with Medically Intractable Frontal or Temporal Lobe Epilepsy: Results and Highlights of 40 Years' Experience. Epilepsia, 34: 244-247.
There are different types of epilepsy common in different stages of childhood.
Epilepsy can be described as “abnormal hypersynchronous electrical activity” due to an imbalance between excitation and inhibition.
Paroxysmal depolarising shift leads to sustained and repetitive or burst firing. During seizures, 1) It is more difficult for potassium to move outwards 2) Calcium accumulates, so more neurotransmitter is released 3) Activation of NMDA by glutamate. Terminated with chloride entering, potassium leaving or inactivation of inward current.
GABA is a neurotransmitter that regulates inhibition, therefore a reduction in GABA leads to less control.
Pediatric epilepsy can be treated with Na+ channel blockers (carbamazepine, phenytoin), GABA receptor agonist (phenobarbital), Ca++ channel blockers (ethosuximide) to prevent frequent firing of neurons.
Intractable pediatric epilepsy may be treated with corpus callosotomy or with ketogenic diet.