Autoimmune thyroid disease: arterial spin-labeling perfusion MR imaging

Area of Science:

• Radiology
• Endocrinology
• Medical Imaging

Background:

• Autoimmune thyroid diseases, such as Graves disease (GD) and Hashimoto thyroiditis (HT), are common endocrine disorders.
• Assessing thyroid gland activity and blood flow is crucial for diagnosis and management.
• Traditional methods for evaluating thyroid function may not fully capture dynamic perfusion changes.

Purpose of the Study:

• To quantitatively assess thyroid perfusion in patients with GD and HT using arterial spin-labeling (ASL) magnetic resonance (MR).
• To compare thyroid perfusion between patients with autoimmune thyroid diseases and healthy controls.
• To investigate the association between thyroid perfusion and endocrine laboratory markers.

Main Methods:

• ASL MR perfusion imaging of the thyroid gland was performed on 10 patients with GD, 10 with HT, and 10 healthy controls using a 1.5-T MR unit.
• Thyroid perfusion maps were calculated using extended Bloch equations.
• Statistical analysis included ANOVA with post hoc tests and univariate regression to compare groups and assess associations with laboratory parameters.

Main Results:

• Mean thyroid perfusion was significantly higher in patients with GD (1596 mL/min/100 g) and HT (825 mL/min/100 g) compared to healthy controls (491 mL/min/100 g).
• Significant differences in perfusion were observed between GD and HT patients (P < .0001).
• In GD patients, perfusion correlated with free thyroid hormones and anti-TSH receptor antibodies.

Conclusions:

• Quantitative ASL perfusion imaging effectively differentiates thyroid perfusion in GD and HT from healthy controls.
• This MR technique provides valuable insights into the pathophysiology of autoimmune thyroid disorders.
• Absolute quantification of thyroid perfusion may assist in clinical assessment and monitoring treatment efficacy, particularly in GD.