The diagnostic value of the ultrasound gray scale ratio for different sizes of thyroid nodules

Abstract

At present, hypoechogenicity, as one of the clinically relevant features associated with suspicion of malignant thyroid disease, is affected by the variability of modules and the experience of sonographers, thus leading to unsatisfying results. We propose the ultrasound gray scale ratio (UGSR) to obtain an objective, numerical estimate of the echogenicity degree in different‐sized thyroid nodules, and we then evaluate its diagnostic efficacy in differentiating benign and malignant thyroid lesions. In total, 553 ultrasound images of thyroid nodules from one kind of ultrasonographic scanner were analyzed, among which 281 were papillary thyroid carcinomas (PTCs) and 272 were nodular goiters (NGs). The UGSR of the PTCs, NGs, and surrounding normal thyroid tissue was measured by image analysis software. The best cut‐off value for distinguishing various sizes of PTCs and NGs was determined by receiver operating characteristic (ROC) curve analysis. As the UGSR increased, the sensitivity of the diagnosing PTCs decreased, and the specificity increased. When the maximum Jordan index was 0.611, the best cut‐off value was 0.692, and the corresponding sensitivity and specificity of diagnosing PTCs were 87.9% and 73.2%, respectively. For the analysis of subgroups of different tumor sizes, as the size of thyroid nodules increased from 0.3 to 2 cm, the sensitivity of the diagnosis of PTCs decreased from 97.5% to 58.8%, and the specificity increased from 72.4% to 90.9%. These results strongly suggest that the UGSR is an appropriate objective, numerical method for estimating the echogenicity degree and has various diagnostic efficacies in different‐sized thyroid nodules. Thus, the UGSR can be used as an additional ultrasound parameter in the diagnosis of different‐sized PTCs and NGs.

A Control Study on the Value of the Ultrasound Grayscale Ratio for the Differential Diagnosis of Thyroid Micropapillary Carcinoma and Micronodular Goiter in Two Medical Centers

“…( 7 ) and Chen et al. ( 8 ), the present study has the following three advantages. First, the study included two medical centers, as well as different ultrasound scanners, operators, and cases between the two medical centers, which increases the clinical value of the results.…”

“…Compared with the studies of Giorgio et al (7) and Chen et al (8), the present study has the following three advantages. First, the study included two medical centers, as well as different ultrasound scanners, operators, and cases between the two The present study had several limitations.…”

“…The limitation in the data from our previous studies ( 5 , 6 ) and those from the study by Chen et al. ( 8 ) is that they were obtained in a single medical center, and the data reported by Chen et al. were obtained using two different scanners from the same ultrasound machine manufacturer.…”

“…In 2019, Chen et al. ( 8 ) divided papillary carcinomas and nodular goiters into three groups according to size as follows: 0.3–1.0, 1.0–1.5, and 1.5–2.0 cm. The results showed that the AUC, optimal UGSR threshold, sensitivity, and specificity vary with the size of the tumor.…”

“…Therefore, the echo intensity of the nodule can be indirectly quantified by measuring the ultrasound gray-scale ratio (UGSR) of the nodule to the surrounding thyroid tissues, which is more objective than the naked eye assessment of levels 3–5. Including our previous studies, only four reports of the quantification of thyroid nodules using UGSR have been published to date ( 5 – 8 ). These reports all suggest that the UGSR of malignant nodules is lower than that of solid benign nodules but higher than that of cystic benign nodules.…”