Fine needle aspiration

When a doctor or nurse inserts a needle into the body to remove cells or fluid, this is called an aspiration. An aspiration is performed with a thin, hollow needle.

After the puncture, the contents of the syringe (the aspirate) are sent to the laboratory. A laboratory technician examines them under a microscope to determine whether there are any abnormalities or disease.

Types of puncture

There are different types of puncture, but they have one thing in common. Whatever is removed from the body, it is done using a thin hollow needle. Well-known examples include:

• Taking blood.
• Drawing fluid from a swollen joint.
• Amniocentesis during pregnancy.
• Drawing cells from an inflammation.

Who performs the puncture?

A nurse or doctor performs the puncture. If the puncture must be performed in a difficult-to-reach or more dangerous area, such as the neck, it is carried out in the hospital's radiology department. The puncture then often takes place under ultrasound guidance or during a CT scan. This makes it possible to see whether the needle is in the right place. The puncture is therefore more accurate and comfortable.

How do you prepare for a puncture?

There is not much you can do to prepare for a puncture, but there are a few things to bear in mind:

• Temporarily stop taking anticoagulants, as these increase the risk of bleeding. Do this in consultation with your doctor.
• Do not eat or drink anything for 2 hours beforehand.
• If necessary, ask someone to accompany you to the hospital.

During the puncture

A puncture is not a major procedure. It is usually performed without anaesthesia, unless several needle insertions are needed in the same area.
After disinfecting the skin, the doctor inserts the needle in the correct place. To collect enough cells, the doctor may move the needle slightly up and down. Once enough material has been aspirated, the needle is removed. The puncture is then complete. The examination takes approximately 20 to 60 minutes in total.

After the puncture

You can usually go home immediately after the puncture. A puncture generally does not cause serious side effects. However, the puncture site may remain tender for a few days or a bruise may develop. There is no need to worry about this.

It takes approximately one week to receive the test results. During this time, the aspirate is examined. You receive the results of the laboratory test from the treating doctor or GP.

Difference between a puncture and a biopsy

A puncture and a needle biopsy are sometimes confused. The major difference is that a biopsy removes pieces of tissue from the body rather than only fluid or cells. The doctor uses a thicker hollow needle for this.

Removing tissue for examination during an operation is also considered a biopsy. This is done with a knife or forceps rather than a needle. A biopsy sample usually provides more information about a disease or abnormality than an aspirate.