Fine-needle Aspiration - Procedure

Procedure

The skin above the area to be biopsied is swabbed with an antiseptic solution and draped with sterile surgical towels. The skin, underlying fat, and muscle may be numbed with a local anesthetic, although this is often not necessary with superficial masses. After locating the mass for biopsy, using x-rays or palpation, a special needle of very fine diameter is passed into the mass. The needle may be inserted and withdrawn several times. There are many reasons for this:

• One needle may be used as a guide, with the other needles placed along it to achieve a more precise position.
• Sometimes, several passes may be needed to obtain enough cells for the intricate tests which the cytopathologists perform.

After the needles are placed into the mass, cells are withdrawn by aspiration with a syringe and spread on a glass slide. The patient's vital signs are taken again, and the patient is removed to an observation area for about 3 to 5 hours.