From the Guidelines
The recommended non-invasive test for thyroiditis is Ultrasound and Doppler, as it allows for real-time visualization of the thyroid gland's structure, size, and blood flow patterns without using radiation or invasive procedures. Ultrasound with Doppler imaging is the preferred non-invasive diagnostic tool for thyroiditis, as it provides valuable information on thyroid morphology and can help differentiate between various types of thyroiditis 1. Key benefits of ultrasound and Doppler for thyroiditis diagnosis include:
- Visualizes thyroid enlargement and inflammation
- Detects nodules or cysts
- Assesses blood flow changes associated with thyroiditis
- Helps differentiate between various types of thyroiditis
- Guides further testing or treatment decisions While FNAC (Fine Needle Aspiration Cytology) is useful for diagnosing thyroid nodules, it is invasive and not typically the first-line test for thyroiditis, as noted in a study on thyroid cancer diagnosis 1. Ultrasound and Doppler imaging is safe, painless, and can be repeated as needed for monitoring thyroiditis progression or treatment response. It's often combined with blood tests measuring thyroid hormones and antibodies for a comprehensive thyroiditis evaluation. Doppler US can also distinguish between thyrotoxicosis caused by an overactive thyroid and destructive causes such as subacute or lymphocytic thyroiditis, by showing increased and decreased thyroid blood flow, respectively 1.
From the Research
Non-Invasive Tests for Thyroiditis
- Fine Needle Aspiration Cytology (FNAC) is a diagnostic method used to distinguish Hashimoto's thyroiditis from other thyroid disorders 2
- Ultrasound examination of the thyroid gland is widely used in the diagnosis of thyroid disease, including thyroiditis, and is easy, rapid, and readily interpreted 3
- Ultrasound can facilitate the diagnosis of De Quervain's non-suppurative sub-acute thyroiditis (TANS) and Hashimoto's chronic thyroiditis, although always in association with clinical and laboratory tests 3
- Color Doppler sonography can be useful in the differential diagnosis of unclear cases of thyroiditis, including De Quervain's subacute thyroiditis 4
- Color Doppler ultrasonography has a good diagnostic accuracy for subacute thyroiditis and can provide an important basis for clinical diagnosis and treatment 5
Characteristics of Thyroiditis on Ultrasound
- Irregular margin of the thyroid gland 6
- Fibrosis, necrosis, and lymphadenopathy may be present 6
- Decreased echogenic feature, heterogeneous pattern of echogenecity, and focal nodules may be observed 6
- Mild to moderate enlargement of the involved thyroid gland, local or diffuse inhomogeneous hypoechoic areas, irregular edges, and unclear boundaries may appear 5
- Rich blood flow signal around the hypoechoic area and less internal blood flow signal may be present 5
Diagnostic Value of Color Doppler Ultrasonography
- Color Doppler ultrasonography can be used to diagnose subacute thyroiditis with good diagnostic accuracy 5
- The method is simple, economical, and non-invasive, making it a valuable tool for clinical diagnosis and treatment 5
- Color Doppler sonography can help distinguish thyroiditis from other thyroid disorders, including De Quervain's subacute thyroiditis 4