Thyroid CT number and its relationship to iodine concentration

Area of Science:

• Radiology
• Endocrinology
• Oncology

Background:

• Thyroid disease diagnosis relies on various imaging modalities.
• Computed tomography (CT) offers detailed anatomical visualization.
• Quantitative CT parameters may provide insights into thyroid tissue composition.

Purpose of the Study:

• To investigate the utility of computed tomography (CT) numbers in differentiating various thyroid pathologies.
• To correlate CT findings with tissue iodine concentration.

Main Methods:

• Sixty-seven patients with thyroid disease and 24 healthy controls underwent CT examination.
• Mean CT numbers (Hounsfield units) were calculated for different thyroid conditions.
• Correlation analysis was performed between CT numbers and tissue iodine concentration in a subset of patients.

Main Results:

• Normal thyroids exhibited significantly higher mean CT numbers (118.1 HU) compared to most diseased thyroids (p < 0.001).
• Graves disease (69.5 HU) and Hashimoto thyroiditis (61.4 HU) showed higher CT numbers than adenoma (41.7 HU), cysts (33.1 HU), and cancer (48.7 HU).
• A strong positive correlation (r = 0.889, p < 0.001) was found between thyroid CT numbers and iodine concentration.

Conclusions:

• CT numbers can help distinguish between normal thyroid tissue and various thyroid pathologies.
• CT-derived Hounsfield units may reflect tissue iodine content, offering a non-invasive assessment method.
• Further research is warranted to explore CT's role in routine thyroid disease management.