脑部PET扫描

定义

A brain positron emission tomography (PET) scan is an imaging test of the brain. It uses a radioactive substance called a tracer to look for disease or injury in the brain.

A PET scan shows how the brain and its tissues are working. Other imaging tests, such as magnetic resonance imaging (核磁共振成像)及电脑断层扫描(CT) scans only reveal the structure of the brain and its surrounding tissues.

选择的名字

Brain positron emission tomography; PET scan - brain

如何执行测试

A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), usually on the inside of your elbow. Or, you breathe in the radioactive material as a gas.

The tracer travels through your blood and collects in organs and tissues. The tracer helps your health care provider to see certain areas or diseases more clearly.

You wait nearby as the tracer is absorbed by your body. 这通常需要1个小时.

Then, you lie on a narrow table, which slides into a large tunnel-形状d scanner. PET扫描仪检测来自示踪剂的信号. A computer changes the results into 3-D pictures. The images are displayed on a monitor for your provider to read.

You must lie still during the test so that the machine can produce clear images of your brain. You may be asked to read or name letters if your memory is being tested.

测试时间在30分钟到2小时之间.

如何准备考试

You may be asked not to eat anything for 4 to 6 hours before the scan. 你就可以喝水了.

如果:

• You are afraid of close spaces (have claustrophobia). You may be given a medicine to help you feel sleepy and less anxious.
• 你怀孕了，或者觉得自己可能怀孕了.
• You have any allergies to injected dye (contrast).
• 你服用了胰岛素治疗糖尿病. 你需要特别的准备.

Always tell your provider about the medicines you are taking, 包括那些非处方购买的. Sometimes, medicines interfere with the test results.

考试的感觉如何

You may feel a sharp sting when the needle containing the tracer is placed into your vein.

PET扫描不会引起疼痛. The table may be hard or cold, but you can request a blanket or pillow.

An intercom in the room allows you to speak to someone at any time.

There is no recovery time unless you were given a medicine to relax.

After the test, drink a lot of fluids to flush the tracer out of your body.

为什么要进行测试

PET扫描可以显示大小, 形状, 以及大脑的功能, so your doctor can make sure it is working as well as it should. 它最常用于其他测试, 比如核磁共振扫描或CT扫描, 没有提供足够的信息.

此测试可用于:

• 诊断癌症
• 为癫痫手术做准备
• Help diagnose 痴呆 if other tests and exams 没有提供足够的信息
• Tell the difference between 帕金森病 and other movement disorders

Several PET scans may be taken to determine how well you are responding to treatment for cancer or another illness.

正常的结果

There are no problems detected in the size, 形状, or function of the brain. There are no areas in which the tracer has abnormally collected.

异常结果意味着什么

异常结果可能是由于:

• 阿尔茨海默病 or 痴呆 由于其他健康状况
• 脑瘤 or spread of cancer from another body area to the brain
• 癫痫, and may identify where the seizures start in your brain
• 运动障碍(如 帕金森病)

风险

The amount of radiation used in a PET scan is low. It is about the same amount of radiation as in most CT scans. Also, the radiation does not last for long in your body.

Women who are pregnant or are breastfeeding should let their provider know before having this test. Infants and babies developing in the womb are more sensitive to the effects of radiation because their organs are still growing.

It is possible, though very unlikely, to have an allergic reaction to the radioactive substance. Some people have pain, redness, or swelling at the injection site.

注意事项

It is possible to have false results on a PET scan. Blood sugar or insulin levels may affect the test results in people with 糖尿病.

PET扫描可与CT扫描同时进行. 这种组合扫描称为PET/CT.

参考文献

Barras CD, Bhattacharya JJ. Current status of imaging of the brain and anatomical features. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. 格兰杰 & 艾利森诊断放射学. 7日艾德. Philadelphia, PA: Elsevier; 2021:chap 53.

Glaudemans AWJM, Israel O, Ben-Haim S, Slart RHJA. 血管PET/CT和SPECT/CT. 见:Sidawy AN, Perler BA编. Rutherford's Vascular Surgery and Endovascular Therapy. 10日艾德. Philadelphia, PA: Elsevier; 2023:chap 31.

Jankovic J, Mazziotta JC, Newman NJ, Pomeroy SL. Investigations in the diagnosis and management of neurological disease. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8日艾德. Philadelphia, PA: Elsevier; 2022:chap 34.