Can Thyroid Ultrasonography Predict Substernal Extension or Tracheal Compression in Goiters?

Area of Science:

• Radiology
• Endocrinology
• Surgical Planning

Background:

• Thyroid nodules often require imaging to assess for substernal extension and tracheal compression.
• Computed tomography (CT) is commonly used but involves radiation exposure.

Purpose of the Study:

• To evaluate if ultrasonography (US)-defined thyroid volume can predict substernal extension or tracheal narrowing.
• To establish US volume thresholds for identifying patients at risk.

Main Methods:

• Retrospective analysis of 120 patients with thyroid nodules who underwent both US and CT.
• US thyroid volume was measured and correlated with CT findings of substernal extension and tracheal narrowing.
• Receiver operating characteristic (ROC) curve analysis was used to determine predictive thresholds.

Main Results:

• A US total thyroid gland volume ≥37.5 cm³ demonstrated 83% sensitivity and 79% specificity for substernal extension (AUC=0.84).
• A threshold of ≥37.8 cm³ predicted tracheal narrowing with 89% sensitivity and 87% specificity (AUC=0.90).
• Patients with substernal extension had significantly larger mean thyroid volumes (92.4 cm³ vs 37.6 cm³).

Conclusions:

• US-defined thyroid volume is a reliable predictor of substernal extension and tracheal narrowing.
• US volume measurements can identify patients who may benefit from preoperative CT for surgical and anesthetic planning.
• This approach may help optimize imaging strategies and reduce unnecessary radiation exposure.