What is the management of thyroglossal cysts?

Management of Thyroglossal Cyst

The Sistrunk procedure is the gold standard surgical treatment for thyroglossal duct cysts, involving complete excision of the cyst, the central portion of the hyoid bone, and a core of tissue extending superiorly to the foramen cecum at the base of the tongue. 1, 2

Preoperative Evaluation

Before surgical intervention, confirm the diagnosis and assess thyroid function:

• Thyroid function tests are mandatory to ensure the patient has a normally functioning thyroid gland elsewhere, as the cyst may rarely contain the only functioning thyroid tissue 3
• Ultrasonography of the neck to characterize the lesion and confirm presence of a normal thyroid gland 3
• Fine needle aspiration cytology (FNAC) can be performed, though diagnosis is often clinical 3
• CT or MRI should be reserved for larger cysts or when malignancy is suspected 3

Surgical Technique: The Sistrunk Procedure

The complete Sistrunk operation includes three critical components that must all be removed to minimize recurrence 1, 2:

1. The thyroglossal cyst itself with complete excision of all cyst walls
2. The central portion (minimum 10mm) of the hyoid bone body - this is non-negotiable as the thyroglossal duct passes through or immediately adjacent to the hyoid 1, 4
3. A core of suprahyoid tissue extending from the hyoid superiorly through the base of tongue musculature to the foramen cecum 1, 2

Technical Considerations

• The procedure is performed under general anesthesia 1
• A transverse cervical incision is made over the cyst 2
• Meticulous dissection must trace the tract superiorly, as incomplete removal is the primary cause of recurrence 5
• The specimen should include all three components in continuity 2

Modified vs. Classic Sistrunk Approach

A "conservative" Sistrunk approach (removing cyst, central hyoid bone, and suprahyoid tissue only when macroscopic duct epithelium is visible) has demonstrated excellent results with recurrence rates as low as 0.6% in primary cases 5. However, the classic approach with routine suprahyoid dissection to the foramen cecum remains the safest option, reducing recurrence from approximately 50% with simple cystectomy to 3-5% 2.

Simple cystectomy alone is inadequate and should never be performed, as it results in unacceptably high recurrence rates 4, 5.

Special Situations

Previously Infected Cysts

• History of prior infection significantly increases recurrence risk (p=0.048) 5
• These cases require meticulous technique with complete tract removal 5

Recurrent Cases

• Recurrent thyroglossal cysts require repeat Sistrunk procedure 4
• Scarring from previous surgery increases technical difficulty but the same principles apply 3

Thyroglossal Fistula

• Fistulas result from infected cysts or previous inadequate surgery 3
• Treatment is identical to cysts: complete Sistrunk procedure 3

Absent Normal Thyroid

• If ultrasonography demonstrates absent normal thyroid tissue, the cyst may contain ectopic thyroid 3
• Thyroid replacement therapy must be initiated postoperatively in these rare cases 3

Postoperative Management

• Average hospital stay is 3 days 1
• Blood transfusion is rarely needed 1
• All specimens must undergo histopathological examination to rule out malignancy 3
• Long-term follow-up is recommended to detect rare recurrences 1, 3

Outcomes and Complications

When performed correctly, the Sistrunk procedure has excellent outcomes:

• Recurrence rates of 0-3% in experienced hands 1, 4, 3
• Minimal morbidity 1
• No mortality 1

Complications are rare and include:

• Pharyngo-cutaneous fistula (managed conservatively) 3
• Wound dehiscence (managed conservatively) 3

Critical Pitfall to Avoid

The single most important predictor of recurrence is the type of resection performed (p=0.02 in multivariable analysis) 5. Simple excision of the cyst without hyoid bone resection and suprahyoid dissection is the primary cause of treatment failure and must never be performed 4, 5, 2.