[Sonographic determination of thyroid volume--comparison with surgical data]

Area of Science:

• Endocrinology
• Medical Imaging
• Surgical Pathology

Background:

• Thyroid goitres are common and require accurate volume assessment for treatment planning.
• Ultrasonography is a widely used imaging modality for thyroid evaluation.
• The ellipsoid model is a common method for estimating organ volumes from ultrasound measurements.

Purpose of the Study:

• To evaluate the accuracy of ultrasonography using the ellipsoid model for determining thyroid goitre volume, particularly in large goitres.
• To correlate preoperative ultrasound-derived thyroid volume with postoperative measurements.

Main Methods:

• A prospective study involving 100 patients undergoing thyroid resection.
• Preoperative thyroid volume was measured using ultrasonography by an experienced investigator.
• Volumes were correlated with the sum of surgically removed and postoperative ultrasound-measured thyroid volumes.

Main Results:

• Overall correlation coefficient (r) was 0.90, with a coefficient of variation (CV) of 0.29.
• Excluding retrosternal goitres and large cysts (>2 cm) improved accuracy: r=0.95, CV=0.21.
• Accuracy was not significantly influenced by thyroid volume (< or = 100 ml vs. > 100 ml).
• Deviations were noted in retrosternal goitres (19% +/- 62%), cystic degeneration (41% +/- 52%), and Graves' disease (23% +/- 29%).

Conclusions:

• Ultrasonography, by an experienced examiner, provides sufficiently accurate volume determination for large suprasternal goitres (>100 ml).
• The ellipsoid model is a reliable tool for thyroid volume assessment in various thyroid disorders.
• Careful consideration of specific conditions like retrosternal goitres and cystic changes is necessary for optimal accuracy.