Thyroid test in Seoul, from blood test to ultrasound

What a thyroid test in Seoul includes

Your thyroid gland, at the front of the neck, sets the pace of your metabolism. A thyroid test in Seoul at VEI Clinic is tailored to your question, whether that is checking symptoms, monitoring medication or following up a nodule found during a checkup. Dr. HyunSung Park chooses from the tests below and avoids ordering extras that will not change your care.

• TSH (thyroid-stimulating hormone): the most useful first test for most people
• Free T4, and free T3 in selected cases such as suspected overactive thyroid
• Thyroid antibodies: TPO and thyroglobulin antibodies for Hashimoto's thyroiditis; TSH receptor antibodies for Graves' disease
• Thyroglobulin, for follow-up after thyroid cancer treatment as directed by your specialist
• Thyroid ultrasound, to look at nodules, size and inflammation

Who should consider testing

Thyroid problems are common and often develop slowly, so symptoms are easy to blame on stress or long working hours. Testing is worth considering if you notice:

• Ongoing fatigue, weight change, feeling unusually cold or hot
• Palpitations, tremor, anxiety or poor sleep
• Hair thinning, dry skin, constipation or more frequent bowel movements
• Irregular periods, difficulty conceiving, pregnancy or the months after giving birth
• A lump or swelling in the neck, or a nodule reported on a previous scan
• A personal or family history of autoimmune or thyroid disease
• Medicines that affect the thyroid, such as amiodarone, lithium or certain cancer immunotherapies

How to prepare

Fasting is not needed for routine thyroid blood tests. If you take levothyroxine, we may ask you to take your dose after the blood draw on test day so the result is consistent. High-dose biotin, found in many hair, skin and nail supplements, can falsely change thyroid results on some lab methods, so stop it for two to three days beforehand unless a doctor has prescribed it. Bring a list of supplements, including iodine or kelp, and any previous thyroid results or ultrasound reports.

Results explained 1:1 in English

Routine blood results are usually ready within one to two business days, and antibody tests may take a little longer. Dr. Park explains what your numbers mean in context. A high TSH with low free T4 usually means an underactive thyroid; a low TSH with high free T4 or T3 suggests an overactive one. Mildly abnormal results are common and often simply need rechecking in a few weeks, as illness, recent iodine contrast and some medicines can shift them temporarily. Pregnancy has its own target ranges.

Treatment may include starting or adjusting levothyroxine for an underactive thyroid, or medication and specialist care for an overactive thyroid. Nodules are assessed by their ultrasound features; most are benign, but those with concerning features are referred to a partner hospital for a fine-needle biopsy, and a thyroid uptake scan is arranged there when needed.

Limits, and who should not start here

Thyroid tests are not useful when results would not change anything, for example repeated testing every few weeks without a reason. Borderline results do not always mean you need medication, and taking thyroid hormone without a clear diagnosis can harm your heart and bones. If you had iodine contrast for a CT scan recently and need an uptake scan, timing matters; we plan this with you.

Thyroid ultrasound is a common part of health checkups in Korea, and it finds many small nodules that would never cause harm. Experience in Korea has shown that widespread ultrasound screening of people without symptoms led to many small thyroid cancers being diagnosed and treated without clear benefit. For that reason, Dr. Park recommends ultrasound when there is a reason, such as a lump you can feel, neck symptoms, a risk factor or a previous finding to follow, and explains the trade-offs if you simply want a screening scan.

Thyroid testing is a non-urgent service. If you have chest pain, a very fast or irregular heartbeat with dizziness, severe shortness of breath, confusion, a high fever with agitation, or rapid neck swelling with difficulty breathing or swallowing, call 119 or go to an emergency room.