What role does ultrasound play in the evaluation of thyroid nodules in primary care?

Role of ultrasound in primary care for thyroid nodules:

• Ultrasound is a highly sensitive and specific tool for detecting thyroid nodules and assessing features suggestive of malignancy, such as nodule size, echogenicity, microcalcifications, borders, shape, internal vascularity, and lymphadenopathy, which aid risk stratification and decision-making about further investigations like fine-needle aspiration cytology (FNAC).
• However, routine thyroid or neck ultrasound is not recommended in primary care because it may delay diagnosis and specialist referral; instead, ultrasound should be reserved for cases where malignancy is suspected based on clinical features or when indicated by specialist advice.
• Primary care clinicians should arrange serum thyroid function tests (TFTs) initially to guide referral pathways and management.
• Ultrasound is recommended as the initial diagnostic test when investigating thyroid nodules for malignancy after referral, using an established grading system to guide FNAC decisions.
• Ultrasound guidance is advised when performing FNAC to improve diagnostic accuracy.
• In primary care, monitoring of small, asymptomatic, non-suspicious thyroid nodules (especially those <1 cm without risk factors) can be considered without immediate ultrasound, unless clinical changes occur.

In summary, ultrasound plays a critical role in the detailed evaluation and management of thyroid nodules but is primarily used after specialist referral rather than as a routine investigation in primary care.

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