Three-dimensional Ultrasound Imaging And Malignant Risk Assessment Of Thyroid Nodules

Part 1 Malignant risk assessment based on three-dimensional ultrasound features of thyroid nodulesObjectiveTo evaluate thyroid nodules by the standard of Thyroid Imaging Reporting and Data Systems of American College of Radiology(ACR TI-RADS)and 2015 Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer of American Thyroid Association(ATA guidelines)based on three-dimensional ultrasound characteristics of thyroid nodule,and compare with two-dimensional ultrasound.Methods235 thyroid nodules in 159 patients were prospectively included before thyroidectomy at our center from February 2016 to January 2018.The demographic data and general ultrasonic features of the patients were collected.Two-dimensional ultrasound(2D-US)and Three-dimensional ultrasound(3D-US)were used respectively to evaluate echogenicity,composition,shape,margin,calcifications and extrathyroidal extension of the thyroid nodules.Finally,the nodules were classified by ATA guidelines and ACR TI-RADS grading standard respectively.ResultsAmong the 235 nodules,62 were benign and 173 were malignant.The malignant percentage of 3D-US with unclear boundary,irregular margin and extrathyroidal extension was higher than that of 2D-US(76.3%vs 74.6%;91,3%vs 86.7%;67.6%vs 39.9%),and the malignant percentage of punctate echo was low(43.9%vs 52.0%).Compared with 2D-US,3D-US increased the malignant percentage of high suspicion in ATA guidelines and ACR TI-RADS TR5(97.1%vs 98.2%;90.9%vs 91.7%),and reduced the malignant percentage of Intermediate suspicion in ATA guidelines and ACR TI-RADS TR4(45.5%vs 37.5%;72.7%vs 59.4%).ATA guidelines grading of thyroid nodules in 3D-US showed a slight increase in sensitivity(97.1%vs 98.2%)and a slight decrease in specificity(75.0%vs 72.9%).The sensitivity of ACR TI-RADS grading(86.1%vs 89.0%)and specificity(75.8%vs 79.0%)were slightly elevated.Conclusion3D-US is different from 2D-US in identifying some ultrasonic features of thyroid nodules,and can slightly improve the diagnostic efficiency of ACR TI-RADS classification and partial diagnostic efficiency index of ATA guidelines for thyroid nodules.Part 2 Prospective evaluation of extrathyroidal extension of differentiated thyroid cancer with OmniView of three-dimensional ultrasoundObjectiveThe aim of the present study was to evaluate extrathyroidal extension(ETE)in differentiated thyroid cancer(DTC)with OmniView of three-dimensional ultrasound(3D-OmniView),and compare the efficiency with 2D-US.MethodsThis study prospectively enrolled 180 suspicious malignant thyroid nodules in 132 consecutive preoperative patients at Peking Union Medical College Hospital from February to September 2016.Preoperative 2D-US showed that the distance between the margin of the 180 nodules and the capsule of the thyroid was less than 1 mm.ETE was evaluated with 2D-US and 3D-OmniView.According to the surgical pathology,5 thyroid nodules whose ultrasound images could not be matched with gross pathology,26 benign and 2 medullary thyroid nodules thyroid nodules were excluded.Finally,147 thyroid nodules with DTC in 115 patients were included.ResultsAmong the 147 nodules,144 were papillary carcinomas,3 were follicular carcinomas.The maximum diameter of the 85 thyroid nodules was<1.0 cm,62 thyroid nodules>1.0 cm.ETE was present in 66.7%(98/147)of nodules.The sensitivity and specificity of 2D-US and 3D-OmniView was 49.0%vs 77.6%and 87.8%vs 85.7%.For nodules ? 1 cm and nodules>1 cm,the sensitivity of 2D-US and 3D-OmniView was 36.2%vs 66.0%and 60.8%vs 88.2%.Conclusion3D-OmniView was better than 2D-US in diagnosing ETE of DTC,especially in the sensitivity of thyroid nodules smaller than 1 cm.Part 3 Evaluation of egtrathyroidal extension of differentiated thyroid cancer with TUI of three-dimensional ultrasoundObjectiveThe aim of the present study was to evaluate extrathyroid extension(ETE)in differentiated thyroid cancer(DTC)with Tomographic Ultrasound Imaging(TUI)of three-dimensional ultrasound(3D-US),and compare the efficiency with 2D-US.MethodsThis study prospectively enrolled 274 suspicious malignant thyroid nodules in 168 preoperative patients at Peking Union Medical College Hospital from February to January 2018.ETE was evaluated with 2D-US and 3D-TUI.20 thyroid nodules whose distance to the capsule of the thyroid was greater than 1 mm,15 thyroid nodules whose ultrasonic images could not be matched with gross pathology,62 benign and 2 medullary thyroid nodules thyroid nodules were excluded.Finally,173 thyroid nodules with DTC in 143 patients were included.ResultsAmong the 173 nodules,the maximum diameter of the 100 thyroid nodules was? 1.0 cm,73 thyroid nodules>1.0 cm.ETE was present in 66,5%(113/173)of nodules.The sensitivity and specificity of 2D-US and 3D-TUI was 50.4%vs 80.0%and 82.8%vs 77.6%,respectively.For nodules ? 1 cm and nodules>1 cm,the sensitivity of 2D-US and 3D-OmniView was 36.4%vs 69.1%and 63.3%vs 90.0%.Conclusion3D-TUI was better than 2D-US in diagnosing ETE of DTC,especially in thyroid nodules smaller than 1 cm.