Comparison of Extended Field of View and Dual Image Ultrasound Techniques for the Measurement of the Longitudinal Dimension of Enlarged Thyroid Glands

Abstract

Extended field of view (EFOV) ultrasound (US) provides images with a large anatomic field of view and is a technical modification of conventional US. In this study, we aimed to assess the role of EFOV US in the accurate measurement of the longitudinal dimension of hyperplastic thyroid glands which were too big to be documented in a single image. In addition, the accuracy and reliability of EFOV US were compared with those of dual image US. The actual longitudinal dimensions of 22 surgical specimens of thyroid glandular lobes excised by thyroidectomy were measured manually in the postoperative period. The longitudinal dimensions were also measured by two radiologists using EFOV US and dual image US after the surgical specimens were being placed in containers filled with gel. The accuracy and the reliability of EFOV US ( r = 0.997–0.999; reproducibility, 99.88%; repeatability, 99.88–99.92) were found to be higher than the dual imaging technique ( r = 0.970–0.986; reproducibility, 99.51%; repeatability, 99.56–99.59) in measuring the longitudinal dimension of enlarged thyroid glands. However, our results revealed that both US techniques can be considered in the evaluation of hyperplastic thyroid gland size. Dual image US should be regarded as the second choice for longitudinal dimension measurement of hyperplastic thyroid glands. Based on our findings, we propose the use of EFOV US for accurate and reliable measurements in patients with an enlarged thyroid gland. EFOV US has a crucial role in the diagnosis and follow-up of patients undergoing medical therapy for diffuse or nodular goiter.