User:P J McGill/Racine Stages

Introduction

In epileptic patients, electrical signals reach a threshold causing a spread of firing neurons in the human brain. While an EEG is able to determine the presence of a seizure, the overall result on the body is hard to determine. In 1972, Ronald J. Racine developed a method to split the severity of seizures into stages: Mouth and facial movement,Head nodding,Forelimb clonus,Rearing with forelimb clonus,Rearing and falling with forelimb clonus. Racine stages can be used to determine at what stages the patient is experiencing a seizure. Mappings for patients can be made by sending electrical signals at different strengths to measure the body's reaction. Once the epileptic patient experiences a seizure, the patient becomes more susceptible to having seizures. Racine stages were developed using an animal model to outline the five stages.

Development

A seizure is described as large amounts of synchronized action potentials that cause the body to preform uncontrollable muscle movements. . This synchronized action potential must surpass a threshold that reverberates throughout the body. For Epileptic patients, seizure occur constantly and continue to grow in intensity. A highly tested epileptic patient,HM, showed small signed of seizures while growing up. Before the age of fifteen HM's only sign of a seizure was a lull in the conversation. Some described him as absent minded for a few seconds. His first traumatic seizure happened while he was fifteen. While in the family car, HM experienced a seizure that caused his entire body to convulse.) Prior to Racine's research into epilepsy, a model for the severity of a seizure was not known. In 1972, Ronald J. Racine sought to develop model that quantified the severity of a seizure. Using animal testing (rat model), Racine was able to stimulate specific parts of the brain using slight electrical impulses. He specifically targeted the Hippocampus and the amygdala. Once excited, the rats would demonstrate signs of a seizure. Racine was able to categorize the bodies reaction to the stimulus into five different categories. These stages of increasing severity can serve as a way to quantify a seizure.

Classical Stages

As the intensity of the seizure increases, the sevarity efferent actions increase.

Racine Stages

• Mouth and facial movement
• Head nodding
• Forelimb clonus
• Rearing with forelimb clonus
• Rearing and falling with forelimb clonus (generalized motor convulsions)

As the level of stimulus increases the resulting involuntary movement goes down the level of stages. Levels further down the Racine stages also contain symptoms of previous stages. For example, a person who is demonstrating the actions of a stage 4 seizure will also demonstrate head nodding (indicative of a level two seizure).

This video demonstrates a range in the severity of seizures which all fall into the five classical stages when a stimulus that causes seizures is added to the rat model.

Clinical Uses

Currently, Racine stages are still being used today in rat models. While this model serves as the standard for a method to quantify the severity of a seizure, additional stages have been added to model the more sever cases. In 1978,Pinel and Rovne developed a model that added to the traditional 5 stages. While these stages are based on the classic five stages, the increase in severity called for 5 additional stages. Pinel & Rovne additional stages

• multiple stage five seizures
• Jumpung
• Running
• Jumping and running
• two different seizures with a partial seizure in-between

Stages 6-10 also include the addition of symptoms seen in stages 1-5. Research into the cure for epilepsy is still ongoing. In most cases treatment from medication or surgery can help limit the prevalence of seizures. However, these treatment methods do not always cure the patient.. The use of the ricine stages can help further research into new solutions.