Percutaneous ethanol injection (PEI) is a minimally invasive, office-based procedure that permanently eliminates benign thyroid cysts — without surgery, without general anesthesia, and with a success rate exceeding 90%.
Ethanol ablation, formally called percutaneous ethanol injection (PEI), is a non-surgical technique in which pure ethanol (alcohol) is injected directly into a thyroid cyst under ultrasound guidance. The ethanol destroys the cyst lining, causing it to collapse and scar shut permanently. Dr. Guttler has performed ethanol ablation for over two decades and considers it the treatment of choice for recurrent benign thyroid cysts — far preferable to repeated aspirations or surgery.
Patient Story
Carol, 61
Carol had a large thyroid cyst that had been aspirated four times over three years. Each time it refilled within weeks, causing pressure in her neck and difficulty swallowing. Her surgeon recommended thyroidectomy. Before proceeding, she sought a second opinion from Dr. Guttler. He performed ethanol ablation in the office under local anesthesia. The procedure took 20 minutes. At her six-week follow-up ultrasound, the cyst had collapsed completely. Now two years later, it has not returned. 'I can't believe I almost had surgery for something that was fixed in 20 minutes,' Carol said.
PEI involves inserting a fine needle into the thyroid cyst under real-time ultrasound guidance, aspirating the cyst fluid, and then injecting a small volume of 99% ethanol into the cyst cavity. The ethanol causes chemical sclerosis — it destroys the epithelial cells lining the cyst wall, preventing fluid reaccumulation. The ethanol is then re-aspirated or left in place depending on cyst size and technique.
PEI is ideal for patients with benign, predominantly cystic thyroid nodules (more than 50% fluid content) that are symptomatic or recurrent after simple aspiration. It is particularly effective for pure cysts and complex cysts with a large fluid component. Solid nodules are better treated with radiofrequency ablation (RFA). All candidates require prior FNA biopsy confirming benign cytology.
The procedure is performed in the office under local anesthesia. Using ultrasound guidance, the cyst is aspirated completely, and then 25–50% of the aspirated volume is replaced with ethanol. The patient may feel mild warmth or pressure during injection. The ethanol is left in place for 2–5 minutes, then re-aspirated. Most procedures take 15–30 minutes. Patients go home immediately afterward.
Studies consistently show that PEI achieves permanent cyst resolution in 85–95% of cases after one or two sessions. Volume reduction of 80–100% is typical. Recurrence rates are far lower than with simple aspiration alone (which has a recurrence rate of 50–80%). Complications are rare and include transient pain, mild fever, and very rarely, voice changes if ethanol leaks near the recurrent laryngeal nerve.
Surgery for a benign thyroid cyst carries risks of general anesthesia, permanent hypothyroidism, recurrent laryngeal nerve injury, and hypoparathyroidism. PEI eliminates these risks entirely. It is performed in the office, costs a fraction of surgery, and preserves all normal thyroid tissue. For recurrent benign cysts, PEI should always be considered before recommending thyroidectomy.
Dr. Guttler trained in ethanol ablation techniques in Europe and has been one of its leading advocates in the United States. He has performed hundreds of PEI procedures and has published and lectured on the technique. He offers ethanol ablation consultations for patients with recurrent thyroid cysts who wish to avoid surgery.
Ethanol Ablation for Thyroid Cysts
Recurrent thyroid cysts can be permanently eliminated with a simple office procedure. Dr. Guttler explains percutaneous ethanol injection — how it works and who benefits.
Thyroid Nodules: What You Need to Know
Most thyroid nodules are benign, but some require evaluation. Dr. Guttler explains ultrasound, biopsy, and when to consider ablation instead of surgery.
Lecture 4: Goiter & Benign Thyroid Nodules
Most thyroid nodules are benign. Dr. Guttler explains what causes goiters and nodules, how they are evaluated, and when treatment is needed.