Ultrasound Guided Fine Needle Aspiration
Fine needle aspiration is the most common method used for the diagnosis of a suspicious nodule. The procedure may also be referred to as needle biopsy which employs a hollow needle to remove small fragments of tissue for diagnosis. This procedure is performed under ultrasound guidance for accurate placement of the needle and identification of the suspicious tissue lesion.
Structure of the equipment
The equipment consists of a thin needle with a small bore, to aspirate the cells, and an ultrasound imaging device for visualization of the nodule and to guide the entire procedure.
The procedure is usually performed by a specially trained radiologist on an outpatient basis. The site for the insertion of the needle is cleansed with an antibacterial agent. In some cases a local anaesthetic may be administered around this region. A small amount of water soluble gel is applied on the skin over the gland and an ultrasound transducer is placed over it. The radiologist inserts the needle into the skin under the ultrasound guidance to identify the location of the nodule for the sample. After the collection of the sample, the needle is removed and pressure is applied over the site of insertion to stop the bleeding, if required a bandage may be used for dressing.
The benefits of the ultrasound guided FNA are as follows:
- Accurate placement of the needle for sample collection
- Less invasive
- Less painful
- Recovery time is short and patient can immediately resume their normal activities
The risks of the ultrasound guided FNA include:
- Bleeding at the site of insertion
- Infection at the site of biopsy
- Injury to the adjacent structures