A retrospective study of reducing unnecessary thyroid biopsy for American College of Radiology Thyroid Imaging Reporting and Data Systems 4 assessment through applying shear wave elastography

ABSTRACT Objective The purpose of the study is to quantitatively assess shear-wave elastography (SWE) value in American College of Radiology Thyroid Imaging Reporting and Data Systems (ACR TI-RADS) 4. Materials and methods One hundred and fifty-two ACR TI-RADS 4 thyroid nodules undergoing SWE were included in the study. The mean (EMean), minimum (EMin) and maximum (EMax) of SWE elasticity were measured. Results The areas under the receiver operating characteristic (ROC) curves for SWE EMean, EMin and EMax in detecting benign and malignant nodules were 0.95, 0.83 and 0.84, respectively. Cut-off value of EMean ≤ 23.30 kPa is able to downgrade the lesion category to ACR TI-RADS 3 and cut-off value of EMean ≥ 52.14 kPa is able to upgrade the lesion category to ACR TI-RADS 5. Conclusions The EMean of SWE will probably identify nodules that have a high potential for benignity in ACR TI-RADS 4. It may help identify and select benign nodules while reducing unnecessary biopsy of benign thyroid nodules.

A retrospective study of reducing unnecessary thyroid biopsy for American College of Radiology Thyroid Imaging Reporting and Data Systems 4 assessment through applying shear wave elastography.

Objective The purpose of the study is to quantitatively assess shear-wave elastography (SWE) value in American College of Radiology Thyroid Imaging Reporting and Data Systems (ACR TI-RADS) 4. Materials and methods One hundred and fifty-two ACR TI-RADS 4 thyroid nodules undergoing SWE were included in the study. The mean (EMean), minimum (EMin) and maximum (EMax) of SWE elasticity were measured. Results The areas under the receiver operating characteristic (ROC) curves for SWE EMean, EMin and EMax in detecting benign and malignant nodules were 0.95, 0.83 and 0.84, respectively. Cut-off value of EMean ≤ 23.30 kPa is able to downgrade the lesion category to ACR TI-RADS 3 and cut-off value of EMean ≥ 52.14 kPa is able to upgrade the lesion category to ACR TI-RADS 5. Conclusions The EMean of SWE will probably identify nodules that have a high potential for benignity in ACR TI-RADS 4. It may help identify and select benign nodules while reducing unnecessary biopsy of benign thyroid nodules.

[Net carbon exchange and its driving factors of Haloxylon ammodendron plantation in the oasis-desert ecotone of Minqin, China]. / 民勤绿洲-è’æ¼ è¿‡æ¸¡å¸¦æ¢­æ¢­äººå·¥æž—å‡€ç¢³äº¤æ¢åŠå ¶å½±å“å› å­.

Carbon fluxes in a Haloxylon ammodendron plantation in the oasis-desert ecotone of Minqin was measured using an eddy covariance system. To provide scientific data for carbon source/sink assessment, we quantitatively analyzed the characteristics of CO2 flux and its driving factors in the growing season from May to October, 2018. The results showed that the trend of daily net carbon exchange in the growing season followed a symmetrical "U" shape curve. As to seasonality, bimodal curve was obvious. The plantation ecosystem was a carbon sink every month. The total carbon sequestrated was 34.38 g C·m-2, with the peak of 12.31 g C·m-2 in September and the lowest value of 0.89 g C·m-2 in July. The net carbon exchange in this ecosystem increased during the daytime with the increasing photosynthetically active radiation, consistent with the Michaelis-Menten rectangular hyperbola change. When the vapor pressure deficit was greater than 2.5 kPa, the increasing trend tended to flat. Ecosystem respiration increased exponentially with temperature, with temperature sensitivity being 1.7. Net carbon exchange in either day or night was significantly correlated with soil temperature through the whole growing season.

Is ultrasound combined with computed tomography useful for distinguishing between primary thyroid lymphoma and Hashimoto's thyroiditis?

INTRODUCTION: The aim of the study is to investigate the usefulness of ultrasound combined with computed tomography (CT) for distinguishing between primary thyroid lymphoma (PTL) and Hashimoto's thyroiditis (HT). MATERIAL AND METHODS: The investigation was conducted retrospectively in 80 patients from January 2000 to July 2018. All patients underwent pathological tests to be classified into one of two groups: PTL group and HT group. The cut-off value of CT density was determined using receiver-operating characteristic (ROC) curve analysis. The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of diagnosis for thyroid by CT alone, ultrasound alone, and the combination of CT plus ultrasound were calculated. RESULTS: Of the 80 study patients, 27 patients were PTL and 53 patients were HT. Mean CT density had a sensitivity of 90.6% and a specificity of 88.9% at a cut-off value of 53.5 HU, with area under the curve (AUC) 0.88. Ultrasound combined with CT had the highest specificity, accuracy, and PPV compared with CT alone and ultrasound alone (p value < 0.05). CONCLUSIONS: Features such as extremely hypoechogenicity, enhanced posterior echo, cervical lymphadenopathy in ultrasound image, and linear high-density strand signs, and very low density in CT imaging have high sensitivity and specificity in thyroid lymphoma. Therefore, ultrasound combined with CT may be useful for distinguishing between PTL and HT.