Thyroid Ablation: The Basics
Thyroid ablation refers to a range of non-surgical, minimally invasive techniques for thyroid nodule treatment. These techniques can be used instead of surgery to treat thyroid nodules and cysts. Some small thyroid cancers may also be eligible for these techniques. There are two main forms of thyroid ablation: chemical ablation and thermal ablation.
Chemical Ablation
- The most widely used thyroid chemical ablation technique is ethanol
- Ethanol ablation is particularly effective for thyroid cysts. Thyroid cysts are thyroid masses that predominantly contain fluid over solid tissue (whereas nodule contain more solid tissue than fluid although both components can be present)
- Simple removal of fluid from thyroid cysts using a thin needle in the office rarely cures the problem and the cyst usually comes back.
- In ethanol ablation, the fluid is first removed with a needle and the cyst is washed out with saline (sterile salt water). Pure ethanol is then infused into the cyst using the same needle and left within the cyst for 2-5 minutes before being withdrawn. Occasionally 1-2 mL of ethanol is left within the cyst to facilitate adequate ablation.
- Ethanol causes cell death and scarring which, in approximately 80% of cases, prevents the cyst from recurring.
- The image below shows a symptomatic right thyroid cyst. The video shows ethanol being instilled into the collapsed cyst after its internal fluid has been removed.
Thermal Ablation
- Thermal ablation techniques use heat (of varying forms) to cause cell death and scarring.
- Thermal ablation techniques include radiofrequency ablation, laser ablation, microwave ablation and high intensity focused ultrasound ablation.
- Radiofrequency ablation (RFA) is likely the most effective of the thermal ablation techniques
- RFA is performed as an outpatient under local anesthesia. A slender, specially designed, internally cooled electrode is introduced through the skin and guided (using ultrasound) into the target thyroid lesion. The energy is delivered to multiple areas within the nodule to obtain a homogeneous ablation. Dr Sinclair will explain the technique in greater detail when you meet with her.
- The ablation takes anywhere from 15-45 minutes depending on the size and consistency of the thyroid lesion.
- The nodule does not shrink immediately but will shrink over the subsequent 6-12 months following ablation.
- The videos below show nodules undergoing ablation.