뇌전증(epilepsy), 발작(Seizure)

# Seizure (Epileptic seizure 뇌전증 발작) : 대뇌 겉질의 신경세포들이 갑작스럽고 무질서하게 과흥분함으로써 나타나는 신체증상. 뇌세포에서 통제되지 않은 전기 신호가 생김으로써 환자의 행동, 운동, 생각, 느끼는 방식에 일시적으로 영향을 주는 것.

 

# Epilepsy (뇌전증) : 단일한 뇌전증 발작을 유발할 수 있는 원인 인자, 즉 전해질 불균형, 산-염기 이상, 요독증, 알코올 금단현상, 심한 수면박탈상태 등 발작을 초래할 수 있는 신체적 이상이 없음에도 불구하고, 뇌전증 발작이 반복적으로(24시간 이상의 간격을 두고 2회 이상) 발생하여 만성화된 질환군을 의미한다. 또는, 뇌전증 발작이 1회만 발생하였다고 하더라도 뇌 영상검사(뇌 MRI 등)에서 뇌전증을 일으킬 수 있는 병리적 변화가 존재하면 뇌전증으로 분류

 

# Seizure Types : 뇌에 발생한 이상 전기 신호가 일부분이냐, 전체적이냐에 따라 seizure 양상이 달라짐.

 

1. Focal Onset Seizures

Focal onset (formerly known as partial seizures) means the seizure starts in just one small region of the brain. It may spread to other areas of the brain.

These seizures can often be subtle or unusual and may go unnoticed or be mistaken for anything from being intoxicated to daydreaming. About 60% of people with epilepsy have focal onset seizures – which are also simply known as focal seizures.

Focal onset seizures can be further divided into two groups relating to a person’s awareness during a seizure:

• Focal aware: the person is fully aware of what’s happening around them but may not be able to talk or respond (formerly known as simple partial seizures). They are usually brief, and are often called a warning or ‘aura’ (that a more significant seizure may develop) but are actually part of the seizure.
• Focal impaired awareness: awareness is affected (formerly known as a complex partial seizure) and the person may appear confused, vague or disorientated.

A focal seizure may progress to a bilateral tonic-clonic seizure meaning that it starts in one area of the brain and then spreads to both sides causing muscle stiffening and jerking.

 

2. Generalised Onset Seizures

Generalised onset means the seizure affects both hemispheres (sides) of the brain from the onset. Because of this, a person may lose consciousness at the start of the seizure. Generalised onset seizures almost always affect awareness in some way, so the terms ‘aware’ or ‘impaired awareness’ aren’t used. However, they can be classified further by movement:

• Generalised motor seizure: may involve stiffening (tonic) and jerking (clonic), known as tonic-clonic (previously known as grand mal) or other movements
• Generalised non-motor seizure: These seizures involve brief changes in awareness, staring, and some may have automatic or repeated movements like lip-smacking.

Types of Generalised Onset Seizures

There are many types of seizures in this classification. They include:

• Absence – a sudden lapse in awareness and responsiveness that look like brief staring spells or daydreaming
• Tonic-Clonic – the body stiffens (the tonic phase) and then the limbs begin to jerk rhythmically (the clonic phase)

• Myoclonic – sudden single jerks of a muscle or a group of muscles that may last no more than a second or two

• Tonic – Can occur when a person is asleep or awake and involves a brief stiffening of the body, arms or legs. The person will suddenly fall if standing or sitting.
• Atonic – brief seizures that cause a sudden loss muscle tone and the person often falls to the ground or will have a sudden head nod if sitting.
• Clonic – although uncommon they cause jerking in various parts of the body

 

# 나이에 따른 뇌전증 주요 원인

 

# Treatment : 뇌전증 양상에 따라 치료약 선택, Seizure가 나타나지 않는 적정 용량까지 증량 혹은 다른 뇌전증약(AED : Antiepileptic drug) 추가

 

# Reference

-대한뇌전증학회, 뇌전증의 약물치료지침

-Epilepsy Action Australia, Seizure Classification Factsheet