Thyroid needle aspiration

What it is and when it is done

Thyroid fine needle aspiration is a minimally invasive diagnostic procedure, which is used when it is necessary to confirm or exclude the malignant nature of a thyroid nodule.

thyroid nodules - which are cell clusters detectable on palpation and / or through diagnostic techniques such as ultrasound and gland scintigraphy - are malignant in about 5% of cases. The risk is far greater if the nodule appears cold, therefore not functioning, ultrasonographically solid, with dimensions equal to or greater than 1 cm and / or with small calcifications or vessels inside.

The diffusion of the thyroid aspirate has made it possible to reduce the number of surgical removal operations of the gland and above all to limit them to well-selected cases, in which there is sufficient evidence about the malignancy of the thyroid nodules.

How is the needle aspiration performed?

Thyroid fine needle aspiration is a fairly simple and safe technique, which is used when a lump shows suspicious ultrasound and scintigraphic features.

It is performed on an outpatient basis, with the patient lying on his stomach and with the head extended backwards on a pillow. Normally no anesthesia is required, neither local (sometimes practiced) nor general; the examination can also be conducted during pregnancy and there are no particular contraindications.

On the other hand, the cytological reading of the aspirated material is more complex, which must be carried out by expert personnel (the diagnostic accuracy can thus exceed 90%).

After these preliminary operations, the doctor carefully disinfects the anterior region of the neck and, under ultrasound guidance, inserts a particularly thin needle inside the thyroid nodule. In this way it is possible to aspirate a minimum amount of cellular material, which is then swiped. and fixed on slides to be stained and analyzed under the microscope (cytological examination).

The puncture and aspiration procedure is rather quick, it involves a number of samples in different points for each node and the pain connected to it is mild and well bearable. Ultrasound guidance also minimizes the risk of complications from damage to vital neck structures, such as veins, arteries, and nerves (laryngeal nerve injury can cause hoarseness).

Possible Complications

In a small percentage of cases (less than 5%), after a thyroid aspiration small hematomas may form inside the thyroid, painful but destined to spontaneously reabsorb within a few days. Rarely, after the examination, the pain can exceed the simple discomfort and in this case can be effectively calmed with common over-the-counter analgesics and anti-inflammatories.

Prepare for the Exam

Fasting is not necessary before the thyroid aspiration; however, it is important to suspend any antiplatelet treatments (aspirin, ticlopidine, etc.) in accordance with the doctor's instructions.