Interobserver and Intraobserver Reliability in Sonoelastographic Assessment of Thyroid Nodules.

BACKGROUND: Thyroid ultrasonography is the first and perhaps most fundamental step for the radiological distinction of benign and malignant nodules. In this study, 2 radiologists reviewed the sonoelastographic and Doppler images of thyroid nodules and evaluated for the intraobserver and interobserver reliability. PURPOSE: We aimed to determine confusing nodule identifiers and sonographic features differently defined by observers. METHODS: A total of 157 nodules in 91 patients (male/female, 72:19) with ages ranging from 18 to 72 years old were included in the study. Ultrasonographic images and video clips of the nodules were obtained and presented to 2 reviewers unaware of the cytopathology results. Two observers defined the characteristics of the nodules based on previously determined criteria. Then, intraobserver and interobserver correlation coefficients were calculated for each subcategory. RESULTS: In the grayscale ultrasonographic examination, varying degrees from low to high interobserver correlation coefficients were obtained for different subcategories (between κ = 0.359 and κ = 0.821). In color Doppler examination, we obtained medium correlation coefficients ( κ = 0.493 and κ = 0.553). On the other hand, there was a high correlation coefficient in tissue compression elastography ( κ = 0.617 and κ = 0.638).According to our study results, elastographic pattern, shape of the nodule, presence of echogenic foci, and pathological lymph nodes are better predictors to determine the malignant potential of thyroid nodule with higher interobserver correlation. Therefore, these criteria may be used primarily for the evaluation of thyroid nodules. The intraobserver correlation coefficient was higher in the practitioner with longer experience, suggesting the importance of professional practice period on the decision-making process.

Assessment of Peripheral Nerves With Shear Wave Elastography in Type 1 Diabetic Adolescents Without Diabetic Peripheral Neuropathy.

OBJECTIVES: To investigate the utility of shear wave elastography (SWE) in detecting morphologic abnormalities of the median nerve and posterior tibial nerve in transverse and longitudinal axes in adolescents with type 1 diabetes mellitus (DM) without diabetic peripheral neuropathy (DPN). METHODS: The median nerves and posterior tibial nerves of 25 adolescents with diagnosis and follow-up of type 1 DM without DPN and 32 healthy volunteers were evaluated with SWE by 2 observers on the transverse and longitudinal axes. The cross-sectional area and thickness of the nerves and disease duration were noted, and probable associations of these parameters with SWE features were analyzed. Interobserver and intraobserver correlations were also examined. The statistical significance level was set at P < .05. RESULTS: Both the median nerve and posterior tibial nerve were smaller, thinner, and stiffer in the patient group for both observers on both axes. The disease duration weakly correlated with median nerve SWE features (r = 0.245-0391). The thickness and cross-sectional area had no correlations with SWE features. CONCLUSIONS: The median nerve and posterior tibial nerve in adolescents with type 1 DM without DPN have morphologic abnormalities that can be displayed by SWE regardless of the imaging axis. Shear wave elastography may have a potential role in subclinical DPN, but the reliability of the findings is not as high as desirable.

Quantitative Assessment of Thyroid, Submandibular, and Parotid Glands Elasticity With Shear-Wave Elastography in Children.

Tissue elasticity is becoming a more commonly used parameter in evaluation of parenchyma in inflammatory diseases. Considering the changes in the thyroid and salivary glands with adolescence, determination of mean elasticity ranges with a function of age is necessary to apply ultrasound elastography more widely in the pediatric population.The thyroid, submandibular, and parotid glands of 127 healthy volunteers (66 males, 61 females; mean age = 10.3 ± 3.9 years; range = 3-17 years) were evaluated with shear-wave elastography.The mean elasticity values for the thyroid, submandibular, and parotid glands were 14.6 ± 3.3, 11.8 ± 2.2, and 11.8 ± 2.6 kPa, respectively. There was a significant positive correlation between age and elasticity of the thyroid, submandibular, and parotid glands. There was a significant correlation between age and elasticity value of the thyroid gland adjusted for weight and height.This study provided the baseline quantitative elasticity measures of thyroid, submandibular, and parotid glands, which would be a reference for upcoming studies. In addition, an increase in elasticity value in thyroid gland as a function of age independent of change in weight and height was demonstrated.

In vivo assessment of placental elasticity in intrauterine growth restriction by shear-wave elastography.

PURPOSE: In this study, we evaluated the placental elasticity in vivo by shear-wave elastography in pregnant women under follow-up for intrauterine growth restriction (IUGR) and compared the elasticity values to normal pregnancies. MATERIAL AND METHODS: This prospective study included 42 pregnant women with a possible diagnosis of intrauterine growth restriction based on obstetrical grayscale and Doppler ultrasonography and 42 women with a normal pregnancy during the 2nd and 3rd trimester. During follow-up examinations, seven fetuses showed an increased growth and were delivered with a birth-weight above the 10 percentile. However, for statistical purposes we included these seven patients in the IUGR group due to prospective nature of the study. All patients initially underwent obstetrical grayscale and Doppler ultrasonography with measurement of resistivity and pulsatility indices from uterine arteries. Subsequently, elasticity values of the peripheral and central part of the placentas from fetal and maternal surfaces were measured by shear-wave elastography. Following delivery, Apgar scores at 1st and 5th minute, birth weight were collected. For statistical analysis, Mann-Whitney U test was used. ROC curves were plotted and cut-off values for elasticity values were analyzed. RESULTS: Median elasticity values of the central part of the placentas from maternal (28kPa vs 6kPa) and fetal sides (21.5kPa vs 5kPa) were significantly higher in IUGR pregnancies compared to the control group (p<0.001). Similarly, median elasticity values of peripheral part of placentas from maternal (22kPa vs 5.35kPa) and fetal sides (22.5kPa vs 5.3kPa) were significantly higher in IUGR pregnancies compared to the control group (p<0.001). CONCLUSION: Placental stiffness values are significantly higher in patients with IUGR. Shear-wave elastography can be used as a non-invasive, complementary method to gray-scale and Doppler ultrasound for diagnosing IUGR.