脑电图描记器

定义

An electroencephalogram (脑电图描记器) is a test to measure the electrical activity of the brain.

选择的名字

Electroencephalogram; Brain wave test; Epilepsy - 脑电图描记器; Seizure - 脑电图描记器

如何执行测试

The test is done by an electroencephalogram (脑电图描记器) technologist in your health care provider's office or at a hospital or laboratory.

测试方法如下:

• You lie on your back on a bed or in a reclining chair.
• Flat metal disks called electrodes are placed on many spots on your scalp. The disks are held in place with a sticky paste. The electrodes are connected by wires to a recording machine. The machine changes the electrical signals into patterns that can be seen on a monitor or drawn on paper. 这些图案看起来像波浪线.
• You need to lie still during the test with your eyes closed. This is because movement can change the results. You may be asked to do certain things during the test, such as breathe fast 和 deeply for several minutes or look at a bright flashing light.
• You may be asked to sleep during the test.

If your provider needs to monitor your brain activity for a longer period, 需要进行动态脑电图检查. In addition to the electrodes, you will wear or carry a special recorder for up to 3 days. You will be able to go about your normal routine as the 脑电图描记器 is being recorded. Or, your provider may ask you to stay overnight in a special 脑电图描记器 monitoring unit where your brain activity will be monitored continuously. Video recording may be done at the same time to see what you are doing during the various electrical signals.

如何准备考试

考试前一晚洗头. DO NOT use conditioner, oils, sprays, or gel on your hair. If you have a hair weave, ask your health care provider for special instructions.

Your provider may want you to stop taking certain medicines before the test. DO NOT change or stop taking any medicines without first talking to your provider. 带上你的药品清单.

Avoid all food 和 drinks containing caffeine for 8 hours before the test.

考试期间你可能需要睡觉. If so, you may be asked to reduce your sleep time the night before. If you are asked to sleep as little as possible before the test, 不要吃或喝任何咖啡因, 能量饮料, or other products that help you stay awake.

Follow any other specific instructions you are given.

考试的感觉如何

The electrodes may feel sticky 和 strange on your scalp, but should not cause any other discomfort. You should not feel any discomfort during the test.

为什么要进行测试

Brain cells communicate with each other by producing tiny electrical signals, called impulses. 脑电图测量这种活动. It can be used to diagnose or monitor the following health conditions:

• 癫痫发作 和 癫痫
• Abnormal changes in body chemistry that affect the brain
• 脑部疾病，如 阿尔茨海默病 或者某些感染
• 混乱
• Fainting spells or periods of memory loss that cannot be explained otherwise
• 头部受伤
• 感染
• 肿瘤

脑电图描记器还用于:

• 评估睡眠问题(睡眠障碍)
• 在脑部手术中监测大脑

An 脑电图描记器 may be done to show that the brain has no activity, in the case of someone who is in a deep coma. It can be helpful when trying to decide if a person is brain dead.

脑电图描记器 cannot be used to measure intelligence.

正常的结果

Brain electrical activity has a certain number of waves per second (frequencies) that are normal for different levels of alertness. For example, brain waves are faster when you are awake 和 slower in certain stages of sleep.

There are also normal patterns to these waves.

Note: A normal 脑电图描记器 does not mean that a seizure did not occur.

异常结果意味着什么

Abnormal results on an 脑电图描记器 test may be due to:

• 异常出血(出血)
• An abnormal structure in the brain (such as a 脑瘤)
• Tissue death due to a blockage in blood flow (cerebral infarction)
• 吸毒或酗酒
• 头部受伤
• 偏头痛(在某些情况下)
• 发作性疾病(如癫痫)
• 睡眠障碍(如 猝睡症)
• 脑肿胀(水肿)
• 大脑感染
• 肾脏或肝脏疾病

风险

脑电图检查是非常安全的. 闪烁的灯光或急促的呼吸(换气过度) required during the test may trigger seizures in those with seizure disorders. The provider performing the 脑电图描记器 is trained to take care of you if this happens.

参考文献

德卢卡GC，格里格斯RC. Approach to the patient with neurologic disease. 参见:Goldman L, Schafer AI主编. Goldman-Cecil医学. 26日艾德. Philadelphia, PA: Elsevier; 2020:chap 368.

哈恩CD，爱默生RG. Electroencephalography 和 evoked potentials. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley 和 Daroff's Neurology in Clinical Practice. 8日艾德. Philadelphia, PA: Elsevier; 2022:chap 35.