What are the key components of a comprehensive thyroid examination?

Comprehensive Thyroid Examination

A comprehensive thyroid examination should include thyroid function tests (TSH and free T4), ultrasound imaging, and thorough physical examination of the thyroid gland and surrounding structures to accurately assess thyroid health and detect potential abnormalities. 1

Physical Examination Components

Inspection

• Observe the neck for visible enlargement, asymmetry, or obvious nodules 1
• Look for signs of thyroid dysfunction such as exophthalmos (in hyperthyroidism) or puffy face (in hypothyroidism) 2
• Note any surgical scars from previous thyroid procedures 1

Palpation

• Palpate the thyroid gland with the patient's neck slightly extended 1
• Assess for size, consistency, tenderness, and presence of nodules 2
• Evaluate for symmetry between right and left lobes 1
• Check for any fixation to surrounding structures which may indicate malignancy 1
• Examine for cervical lymphadenopathy, particularly in the central neck compartment 3

Auscultation

• Listen for thyroid bruits, which may indicate hypervascular states like Graves' disease 4

Laboratory Assessment

Essential Tests

• Serum TSH measurement (primary screening test for thyroid dysfunction) 1
• Free T4 levels to differentiate between subclinical and overt thyroid dysfunction 1
• Multiple tests over 3-6 months to confirm abnormal findings 1

Additional Tests When Indicated

• Thyroid antibodies (anti-TPO, anti-thyroglobulin) to evaluate for autoimmune thyroid disease 4
• Calcitonin measurement when medullary thyroid cancer is suspected 3
• Comprehensive blood count and coagulation function before any invasive procedures 1

Imaging Studies

Ultrasound

• Ultrasound is the preferred initial imaging method for evaluating thyroid gland and cervical lymph nodes 1
• Assess for nodule characteristics including:
  • Size and number of nodules 1
  • Echogenicity (hypoechoic nodules raise suspicion) 3
  • Margins (irregular borders suggest malignancy) 3
  • Microcalcifications 1
  • Vascularity patterns 1

Advanced Imaging When Indicated

• Contrast-enhanced ultrasound (CEUS) to evaluate blood supply of thyroid nodules 1
• Neck and chest CT to define spatial relationships of large nodules to surrounding structures 1
• CT is particularly useful to assess if nodules extend beyond the sternum or invade the trachea 1

Fine Needle Aspiration (FNA)

• FNA should be performed for nodules >1 cm or <1 cm with suspicious features 3
• Ultrasound-guided FNA is more accurate than palpation-guided 3
• Cytology results should be categorized using the Bethesda System 3
• False-negative results can occur; clinical suspicion should override reassuring FNA results 1

Special Considerations

Screening Recommendations

• No routine screening for thyroid dysfunction in asymptomatic general population 1
• Consider screening in high-risk individuals:
  • Those with personal history of autoimmune disease 1
  • Family history of thyroid disorders 1
  • Previous head/neck radiation 1
  • Patients with genetic syndromes associated with thyroid disease (e.g., PTEN mutations) 1

Common Pitfalls to Avoid

• Relying solely on physical examination to diagnose hypothyroidism (sensitivity and specificity are limited) 2
• Misinterpreting laboratory results during pregnancy or severe illness 5
• Failing to consider medication effects on thyroid function tests (e.g., amiodarone, heparin) 5
• Not recognizing laboratory assay interferences that can cause confusing results 5

Documentation Requirements

• Document all findings systematically, including:
  • Size and characteristics of the thyroid gland 1
  • Presence, location, and features of any nodules 1
  • Results of all laboratory and imaging studies 1
  • Assessment of risk factors for thyroid disease 1

By following this comprehensive approach to thyroid examination, clinicians can effectively evaluate thyroid health and identify potential abnormalities that require further investigation or treatment.