Interobserver and Intraobserver Reliability in Sonoelastographic Assessment of Thyroid Nodules

Area of Science:

• Radiology
• Oncology
• Endocrinology

Background:

• Thyroid ultrasonography is crucial for differentiating benign from malignant thyroid nodules.
• Assessing interobserver and intraobserver reliability in thyroid nodule evaluation is essential for consistent diagnosis.

Purpose of the Study:

• To identify sonographic features that lead to observer discrepancies in thyroid nodule characterization.
• To evaluate the reliability of different ultrasonographic techniques in assessing thyroid nodules.

Main Methods:

• 157 thyroid nodules from 91 patients were reviewed by two radiologists using grayscale ultrasound, color Doppler, and sonoelastography.
• Observers assessed nodule characteristics based on predefined criteria, unaware of cytopathology results.
• Intraobserver and interobserver correlation coefficients were calculated for each imaging modality and feature.

Main Results:

• Interobserver agreement varied across grayscale ultrasound features (κ = 0.359–0.821).
• Color Doppler showed moderate agreement (κ = 0.493–0.553), while tissue compression elastography demonstrated high agreement (κ = 0.617–0.638).
• Elastographic pattern, nodule shape, echogenic foci, and lymph node status were reliable predictors of malignancy with high interobserver correlation.

Conclusions:

• Elastography, nodule shape, echogenic foci, and lymph node assessment are recommended for reliable thyroid nodule evaluation.
• Increased experience positively impacts intraobserver agreement, highlighting the importance of practice in diagnostic accuracy.