Minimally Invasive Thyroid Interventions

Dr. Hussain discusses how he started doing thyroid embolizations. It was born out of a need to replace thyroid RFA, since the thyroid RFA generator was not yet approved in his health system. At Duke, Dr. Sag collaborated with endocrinologists and endocrine surgeons to address a need to treat non-surgical candidates with bulk symptoms. These symptoms can include supine dyspnea, dysphagia, and aspiration risk. Together, they developed an institutional protocol for post-procedural management. Dr. Sag emphasizes that everything an IR needs to perform a goiter embolization is probably already available to them.

Next, the doctors describe how they implemented thyroid embolization in their respective practices. Dr. Sag approached his institution’s weekly tumor board of endocrine specialists to introduce the concept. When talking to non-surgical patients, he offers thyroid embolization as a palliation alternative to tracheostomy and percutaneous gastrostomy as airway protection for patients with aspiration risks. Dr. Hussain describes patients with TR-3 and TR-4 nodules who require repeat FNA. Embolization can be a valuable option for them, since it is a quick outpatient procedure with minimal side effects. Additionally, he communicates to patients that IRs have experience with applying transcatheter embolizations in different spaces in the body and sets the expectation that shrinkage will be a gradual process. Both doctors emphasize the importance of informed consent in a relatively new palliative procedure. In terms of the research landscape for thyroid embolization, Dr. Hussain says that publishing a large retrospective multicenter study would revolutionize the procedure, since it could show efficacy and safety. Dr. Sag believes that RFA and embolization are complementary technologies that can be used in different scenarios.

In terms of goiter location, the easiest ones to access, either by radial or femoral access, are those supplied by an inferior thyroid artery (ITA) coming off the subclavian. For this reason, Dr. Sag mainly embolizes retrosternal ITA-dominant goiters that cause bulk symptoms. The cervical-dominant goiters that are supplied by the superior thyroid arteries involve making a choice about whether to do carotid catheterization or treat with thyroid RFA instead. Another factor to consider is the financial aspect– thyroid embolization is more easily reimbursed by Medicare than RFA is.

Dr. Hussain shares his treatment algorithm, which includes getting a CTA after each consultation, to map out variable anatomy and select hypertrophied vessels. Deep cannulation is key to preventing reflux and non-target embolization. Additionally, he does a two week follow up for post-procedural symptoms and a 2 month imaging appointment. Dr. Sag describes a joint clinic with endocrine surgeons. Every patient gets a visit from each service on the same day, and the doctors are able to convene and make joint decisions based on patient and goiter factors. He recommends getting a cone beam CTA to rule out anastamoses to aerodigestive structures and the cervical spinal cord. In his embolization, he uses 300-500 micron Embospheres and leaves at least one quadrant untreated to spare some thyroid and parathyroid glands. He also administers decadron and a medrol dose pack. Lab follow-up happens at day 7, when most thyroid hormone peaks occur. If patients are still experiencing symptoms after two months, Dr. Sag will consider repeating the embolization.