Table 2.
Likelihood, severity, measures of prevention and treatment of complications of RFA for BTNs
| Complications (likelihood*, severity†) | Clinical features/prognosis | Preventive measures | Treatment |
|---|---|---|---|
| Voice change/hoarseness (0.5–4.7%/2) Dysphonia (1/3) | Occurring during or immediately after ablation/recovering spontaneously within 3 months, except for two who were lost to follow-up[19,39] | Good knowledge of neck anatomy Through the “trans-isthmic” approach and the “moving- shot” technique Undertreating the part near the danger triangle US-guided monitoring of the electrode tip Communication with patients during the procedure[44] | No need treatment for most patient Steroids, if necessary (i.e., prednisone)[22] |
| Brachial plexus nerve injury (1/2) | Numbness and decreased sensation in the fourth and fifth fingers/gradual recovery[8,19] | Good knowledge of neck anatomy; enough US-guidance invention practice Monitoring the electrode tip[19] | |
| Horner syndrome (1/3) | Ocular discomfort and redness of conjunctiva, ptosis, miosis, and anhidrosis of the face/improved slightly, continued to persist[39] | Careful preoperative evaluation Monitoring the active needle tips[39] | Without further treatment |
| Nodule rupture (2/2) | Abrupt neck swelling and pain at the RFA site after the procedure/the breakdown of the anterior thyroid capsule and the communication between intra- and extra-thyroidal lesions at the RF site (US or CT)/recovery well without sequelae[16] | Warning patients the symptoms about nodule rupture | Conservative therapy firstly Antibiotics and/or analgesics Incision and drainage Surgery[16] |
| Needle track seeding (1/3) | No reduction or increased volume of the thyroid nodule following RFA, a newly hypoechoic mass surrounded track of the site of RFA (US)[25,37] | Small needle size At least two separate biopsies Regular follow-up | Surgery |
| Hypothyroidism (1/2–3) | Asymptomatic[19] | Thyroid function test, giving more notice for patients with elevated serum thyroid antibodies | Levothyroxine replacement therapy |
| Transient thyrotoxicosis (1/2) | Asymptomatic/transient, recovery spontaneously | ||
| Pseudocystic transformation (colliquation) (1/1) | Pain and sudden swelling[27] | Corticosteroids (i.e., oral methylprednisolone)[27] | |
| Pain/a sensation of heat (up to 100%/1) | Mild to moderate pain and a sense of heat in the neck or at the ablated site, radiating to the head, gonial angle, ear, shoulder, jaw, or teeth/self-limited[23,31,45] | Local anesthesia[10,15,18] Reducing RF power or transient or stopping ablation during the procedure Sedatives is not recommended[44] | No treatment in most cases and Oral analgesics if necessary (i.e., acetaminophen, paracetamol)[10,17,31] |
| Hematoma (0.9–17.0%/1) | Asymptomatic in general/expanding hypo/anechoic signal surrounding the thyroid lobe or intrathyroid in US/disappearing spontaneously within 1 month[19,33,46] | Medical history about hemorrhaging risk and diseases affecting coagulation (i.e., end-aged liver and renal diseases) pre-RFA; Stop taking drugs associated with a bleeding tendency pre-RFA; Small needle size; Shift needle-electrode insertion and heat administration[27,44] | Manual compression at the site of puncture No need special treatment for most hematoma |
| Vomiting (1/1) | Occurring after ablation | Antiemetics | |
| Diffuse granular hemorrhage (1/2) | Severe pain and anterior neck swelling during the procedure/no sequelae | Oral analgesics for 3 days[17] | |
| Skin burn (1/1–2) | Skin color change, mild pain, and discomfort at the puncture site/resolution without management in five cases[8,19,38] | Trans-isthmic approach Monitoring the active needle tips Application of an ice bag | Application of an ice bag Seek help of plastic surgeon, if necessary[38] |
| Fever (0.27–6.00%/1) | Mild to moderate fever up to 38.5°C after the ablation/recovering spontaneously within 3 days | No additional therapy | |
| Edema/swelling (1/1) | Swelling with pressure symptoms due to increase in nodule and parathyroid tissue/self-limited[19,27] | Steroids (i.e., betamethasone)[10] or oral anti-inflammatory treatment if necessary[35] | |
| Cough (1/1) | Last 10–40 seconds during the procedure[19,39] | Keep appropriate distance between the electrode needle and the trachea | No additional treatment |
| Vasovagal reaction (0.34–2.50%/2) | Bradycardia, hypotension, vomiting, and defecation, sweating, difficulty breathing during the procedure>[19,39] | Pain prevention | Elevation of the patient’s legs and stopping the ablation Calming the patient down |
| Hypertension (2/2) | Increases in blood pressure during the procedure | Monitor blood pressure during the procedure[39] | |
| Muscle twitching (1/1) | Transient[39] | No additional treatment | |
| Muscle twitching (1/1) | Transient[39] | No additional treatment |
*Likelihood is presented in percentage if epidemiologic data exists in literature; if without epidemiologic data, it is presented in numerical scale as follows, 1: Extremely rare (<5 reported cases); 2: rare (≥5 or ≤10 reported cases); † Severity was assessed, 1: Negligible morbidity; 2: Moderate morbidity; 3: Severe morbidity; US: Ultrasound; BTNs: Benign thyroid nodules; RFA: Radiofrequency ablation; CT: Computed tomography.