Ultrasound-Guided Fine Needle Aspiration (FNA) 

Patient Information

Radiology Ultrasound Service

• Author ID:   CY
• Leaflet ref: Rad 020
• Version:     5
• Leaflet title:  Ultrasound-Guided Fine Needle Aspiration (FNA)
• Last review:  May 2024
• Expiry date:  May 2026

What is a fine needle aspiration?

A fine needle aspiration (FNA) is a procedure performed by a practitioner who inserts a fine needle through the skin into a region of the body to obtain a small sample of cells. It is usually performed as an outpatient procedure and is generally safe with a very low complication rate.

An ultrasound-guided fine needle aspiration involves using ultrasound imaging to guide the needle into the area that is being targeted.

Why do I need this test?

Your doctor will have discussed this with you or written to you about the need for a fine needle aspiration or biopsy.

Fine needle aspiration is usually performed when there is an area of abnormal tissue within the body and your clinician requires a sample of this tissue to determine what this abnormal tissue represents.

The sample of cells is sent to a pathology laboratory where it is analysed under a microscope, usually by a Pathology Doctor. This gives the clinician looking after you information regarding any underlying disease process and will help them decide further management. The fine needle aspiration technique is quick and relatively straightforward and aims to avoid bigger and more complex biopsy procedures.

What will happen on the day of your test?

When your test is due to start, a member of staff will show you into the ultrasound room where you will meet the practitioner performing the fine needle aspiration.

The practitioner will explain the procedure, how it will be performed, and the risks involved. Please inform the practitioner performing the procedure if you are on any medication that thins the blood such as warfarin, aspirin and clopidogrel. If you have any questions or concerns, please ask the practitioner.

How is the procedure performed?

The procedure is performed in the ultrasound room, sedation is not routinely given. An ultrasound scan is performed, the skin is cleaned, and the fine needle aspiration is performed under ultrasound guidance.

A fine needle is inserted through the skin to retrieve some cells.

This entire procedure is usually completed in less than 30 minutes, though the time the needle is in the skin is much shorter than this.

What are the risks?

The procedure is tolerated well by most people, though you may experience discomfort for a short time

• Bleeding and bruising at the site of biopsy
• Injury to nearby structures
• Infection

In a minority of cases the fine needle aspiration sample is looked at under a microscope and there are not enough cells to make a definite diagnosis. Where the cell sample is inadequate you may be advised to undergo a repeat fine needle aspiration at a later date.

How do I prepare for the procedure?

There is no special preparation for this test. Please eat and drink normally before your appointment.

Does it hurt?

Most people tolerate fine needle aspiration well and you should only feel minor discomfort during the procedure. Some people may have some discomfort at the site of the biopsy for the first 24 to 48 hours after the procedure, but this is usually relieved by simple painkillers such as paracetamol.

What happens after the procedure?

Recovery time is brief, and patients can soon resume their usual activities. You may eat and drink normally after the procedure.

If you experience severe pain or signs of bleeding such as swelling where the procedure was performed, you should seek medical advice immediately. You can telephone the Ultrasound Department within normal working hours. If outside normal working hours consider attending your local Emergency Department if you think you may be experiencing a serious complication such as bleeding.

What if I have other questions?

If you have any questions which are not answered within this leaflet, please contact the X-ray Department, where your call can be directed to a Sonographer or Radiographer who will be pleased to help you

If you have any doubts, or worries, please just ask. The Ultrasound staff want to make you feel as relaxed as possible. This makes the scan easier for you and means that we get better pictures to aid your diagnosis.

We sometimes have junior medical staff and trainees in our department who may be present at the time of your examination. If you are uncomfortable with this arrangement, please inform the Ultrasound staff at the time of your appointment. This will not affect your care or treatment in any way.

If you cannot attend your appointment, please contact the Ultrasound Department at the hospital where you have been given an appointment so that we can offer your appointment to somebody else.

We will be glad to offer you an alternative appointment and will try our best to accommodate you at a date and time suitable to you.

Please allow plenty of time to park your car.

Contact Details

Royal Albert Edward Infirmary

Wigan Lane Wigan

WN1 2NN

Telephone 01942 8222409

Monday to Friday, 8:30am to 5:00pm

Leigh Infirmary The Avenue Leigh

WN7 1HS

Telephone 01942 264217

Thomas Linacre Centre

Parsons Walk Wigan

WN1 1RU

Telephone 01942 774608