What is the recommended imaging for an outpatient with a sore throat and a palpable swelling just above the thyroid gland on the left side?

Ultrasound is the First-Line Imaging for Sore Throat with Palpable Swelling Above the Thyroid

For a patient with sore throat and palpable swelling just above the thyroid on the left side, ultrasound of the neck should be the initial imaging study of choice. 1

Diagnostic Algorithm for Neck Swelling Above the Thyroid

Step 1: Initial Imaging

• Ultrasound of the neck is the preferred first-line imaging modality for several reasons:
  • Provides high-resolution imaging to determine if the swelling is related to the thyroid gland or adjacent structures 1, 2
  • Cost-effective and does not expose the patient to radiation 2
  • Can characterize whether the mass is solid, cystic, or complex 1
  • Allows for real-time evaluation and can guide fine needle aspiration if needed 2

Step 2: Further Imaging Based on Ultrasound Findings

• If ultrasound suggests thyroid nodule:

  • Evaluate for suspicious sonographic features that might indicate malignancy 1
  • Assess size and relationship to surrounding structures

• If ultrasound suggests non-thyroid pathology or is inconclusive:

  • Contrast-enhanced CT of the neck should be performed as the next step 1
  • CT provides superior spatial resolution and is particularly valuable if there's concern for:
    • Deep neck infection or abscess 1, 3
    • Extension beyond what can be visualized with ultrasound
    • Relationship to major vessels or airway structures 1

Clinical Considerations

Potential Diagnoses to Consider

1. Thyroid-related pathology:

   • Thyroid nodule or adenoma with possible hemorrhage 4
   • Localized thyroiditis (can present in a single lobe) 5
   • Thyroid abscess (rare but possible complication of throat infection) 3
   • Lymphoepithelial cyst of the thyroid 6

2. Non-thyroid pathology:

   • Cervical lymphadenopathy (reactive or malignant)
   • Branchial cleft cyst
   • Lymphovascular malformation

Important Caveats and Pitfalls

1. Do not assume the swelling is thyroid in origin without imaging confirmation. The location "just above the thyroid" could represent:

   • Superior extension of thyroid pathology
   • Lymph node adjacent to the thyroid
   • Parathyroid pathology
   • Other soft tissue mass

2. Avoid unnecessary radiation exposure by starting with ultrasound before proceeding to CT

3. Be cautious with iodinated contrast if thyroid disease is suspected and radioactive iodine therapy might be needed later 1

4. Do not delay imaging if there are concerning features such as:

   • Rapid growth
   • Voice changes
   • Dysphagia or dyspnea
   • Signs of infection (fever, erythema)

By following this evidence-based approach with ultrasound as the initial imaging modality, clinicians can efficiently diagnose the cause of neck swelling while minimizing radiation exposure and optimizing patient care.