How do I correctly order a thyroid‑focused neck ultrasound (including indication, CPT code, patient preparation, and report requirements) for an adult patient with a palpable thyroid nodule and abnormal thyroid function tests?

How to Order a Thyroid-Focused Neck Ultrasound

For an adult patient with a palpable thyroid nodule and abnormal thyroid function tests, order a thyroid ultrasound with the indication "palpable thyroid nodule with abnormal TSH" after first obtaining TSH levels, as ultrasound is the preferred first-line imaging modality for thyroid structural evaluation. 1

Step 1: Check TSH Before Ordering Imaging

• Always measure TSH first before any thyroid imaging, as the TSH result determines the appropriate imaging pathway 1
• For normal or elevated TSH (euthyroid or hypothyroid), proceed directly to thyroid ultrasound 1
• For suppressed/low TSH (thyrotoxic), order ultrasound first to evaluate morphology, then follow with radioiodine uptake scan to determine the cause of thyrotoxicosis 1

Step 2: Order Specifications

Indication to Write:

• "Palpable thyroid nodule with abnormal thyroid function tests - evaluate for nodule characteristics and malignancy risk" 2
• If TSH is suppressed: Add "evaluate for hyperfunctioning nodule" 1
• If compressive symptoms present (dysphagia, dyspnea, dysphonia): Add "evaluate for substernal extension" 1

CPT Code:

• CPT 76536 - Ultrasound, soft tissues of head and neck (e.g., thyroid, parathyroid, parotid), real time with image documentation 2

Patient Preparation:

• No special preparation required - thyroid ultrasound does not require fasting, contrast, or medication adjustments 3, 4
• Patient should wear clothing that allows easy neck access 3

Step 3: Required Report Elements

The ultrasound report must include:

• Thyroid gland dimensions (right and left lobes, isthmus) 1, 3
• Nodule characterization using ACR TI-RADS classification (benign, minimally suspicious, moderately suspicious, highly suspicious) 5
• Specific nodule features: size, composition (solid/cystic), echogenicity, margins, calcifications, vascularity 5
• Cervical lymph node evaluation for suspicious features (microcalcification, cystic change, hyperecho, abnormal blood flow, rounded shape) 2
• Recommendation for fine-needle aspiration if nodules meet size/suspicion criteria 4, 6

Step 4: Post-Ultrasound Algorithm

If TSH is Normal or Elevated:

• TI-RADS 4 or 5 nodules ≥1 cm require ultrasound-guided FNA 7, 6
• Smaller nodules may require FNA based on high-risk features 6

If TSH is Suppressed:

• Order radioiodine uptake scan after ultrasound to differentiate toxic adenoma, toxic multinodular goiter, Graves' disease, or thyroiditis 1
• Hot nodules rarely require biopsy; cold nodules follow the same FNA criteria as euthyroid patients 1, 4

Critical Pitfalls to Avoid

• Never skip TSH measurement before ordering imaging - this leads to inappropriate test selection and wasted resources 1
• Do not order radioiodine uptake scan in euthyroid patients - it has low diagnostic value for determining malignancy and is not recommended 1
• Do not proceed directly to uptake scan in hyperthyroid patients without ultrasound first, as you may miss coexisting malignant nodules requiring biopsy 1
• Ensure the ultrasound is performed by specialists with thyroid sonography expertise and interpreted by experienced radiologists 4
• Do not order routine thyroid screening ultrasound without clinical indication (palpable nodule, abnormal function tests, high-risk history) 4, 6