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Background: Thyroid gland is afflicted by various pathologies ranging from diffuse enlargement (goitre) to nodular lesions, thyroiditis, and malignancy. Presently high resolution ultrasound with color Doppler is the primary imaging modality of choice in morphological evaluation of thyroid gland. It is used to define the nature of the lesion, whether solid or cystic, to differentiate thyroid from extra thyroidal masses, to assess the size of nodule in patients who are under observation or therapy, to monitor patient who are at increased risk of thyroid malignancy especially those with radiation exposure or having a family history, to detect recurrence of thyroid malignancy after surgery and in interventional procedure like guiding in FNAC. Materials and methods: Study was carried out using standard 5-12 MHz frequency probe with grey scale and color Doppler spectrum to evaluate and analysis of different thyroid nodules and taking Ultrasound guided fine needle aspiration cytology and correlate histopathologically. Results: Majority of patients belonged to middle age group between 21-60 years with mean age of 38.2 years. Colloid goitre was most common presentation on ultrasound and it showed wide spectrum of appearance, majority being nodular with anechoic echotexture. Malignant lesions of thyroid were usually hypoechoic, though all hypoechoic lesions were not malignant. (Sensitivity of 75%, specificity of 81.48%, PPV of 37.5% and NPV 95.65%). The most sensitive sign for picking up malignancy on USG were Intralesional vascularity; absent halo sign and regional lymph node Siddharth Zala, C. Raychaudhuri. Evaluation of thyroid lesions with gray scale ultrasound/ color doppler imaging and fine needle aspiration cytology correlation. IAIM, 2019; 6(4): 86-91. Page 87 involvement (sensitivity of 100%) the most specific signs were invasion of adjacent tissue (specificity of 92.59%), Lymphadenopathy (85.18%) and hypoechotexture (81.48%). A combination of signs aid in prediction of malignancy and in guidance for site of FNAC. The most useful combination of sign proved to be Invasion to adjacent tissue, Lymphadenopathy, absent halo, hypoechogenicity, microcalcification and Intralesional vascularity on color flow imaging. Conclusion: The ultrasonographic findings in thyroiditis were usually hetroechogenicity and coarse calcification with diffuse vascularity on color flow imaging. The addition of color flow imaging to gray scale ultrasound had increased the overall sensitivity for diagnosis of thyroiditis (96.87%) and was also highly specific (89.70%)
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Abstract Introduction To evaluate diagnostic accuracy of high-resolution ultrasonography in differentiation of benign and malignant thyroid nodules in comparison to results of guided fine needle aspiration cytology based on the Bayes rule. Objective To assess the validity of ultrasonography results of thyroid nodules in comparison to guided fine needle aspiration cytology findings. Methods This study was done on randomly chosen 80 patients presented with palpable thyroid nodules, undergone real-time sonographic evaluation of thyroid nodules to characterize features, internal consistency, margins, echotexture, calcification, peripheral lucent halo and vascularity. Ultrasonography guided fine needle aspiration cytology studies of thyroid nodules were done. Results Palpable thyroid nodules were highly prevalent in fourth and fifth decades of life with female-male ratio, 4:1. Solid internal consistency was demonstrated by 75% malignant nodules. Hypoechogenicity and intra-nodular micro-calcifications were observed in 92% malignant nodules; 83% malignant nodules had intra-nodular vascularity and absence of peripheral halo. The pre-test prevalence of malignant nodules in the targeted population was 17.5%. As type I error, 2.5% false-positive cases and as type II error, 5.0% false-negative cases were detected. Values of sensitivity and specificity of the ultrasonography test were 71.43 and 96.97%, respectively. Conclusion Malignant thyroid nodules demonstrated ultrasonography characteristics of hypoechoic texture, intra-nodular micro-calcifications, solid consistency, internal vascularity and absence of peripheral halo. The ultrasonography test has 92.5% diagnostic accuracy to differentiate malignant from benign lesions in comparison to the gold standard fine needle aspiration cytology test.
Resumo Introdução Avaliar a precisão diagnóstica da ultrassonografia de alta resolução na diferenciação de nódulos tireoidianos benignos e malignos em comparação com os resultados da citologia de aspiração por agulha fina baseada na regra de Bayes. Objetivo Avaliar a validade dos resultados da USG de nódulos da tireoide em comparação com os resultados obtidos por citologia de aspiração por agulha fina. Método Este estudo foi feito em 80 pacientes selecionados aleatoriamente, que apresentavam nódulos palpáveis da tireoide, submetidos à avaliação ultrassonográfica em tempo real de nódulos da tireoide para estabelecer características, consistência interna, margens, ecotextura, calcificação, halo lucente periférico e vascularização. Foram feitos estudos por citologia de aspiração por agulha fina guiados pela USG dos nódulos de tireoide. Resultados Nódulos palpáveis da tireoide foram altamente prevalentes na quarta e quinta décadas de vida com uma razão sexo feminino-masculino de 4:1. A consistência interna sólida foi demonstrada em 75% de nódulos malignos. Hipoecogenicidade e microcalcificações intranodulares foram observadas em 92% de nódulos malignos; 83% dos nódulos malignos apresentaram vascularidade intranodular e ausência de halo periférico. A prevalência pré-teste de nódulos malignos na população alvo foi de 17,5%. Como erro tipo I, houve 2,5% de casos falso-positivos e como erro tipo II, foram detectados 5,0% de casos falso-negativos. Os valores de sensibilidade e especificidade do exame por USG foram de 71,43 e 96,97%, respectivamente. Conclusão Nódulos malignos da tireoide mostraram características de textura hipoecoica, microcalcificações intranodulares, consistência sólida, vascularidade interna e ausência de halo periférico na USG. O exame por USG tem 92,5% de precisão diagnóstica para diferenciar lesões malignas de benignas em comparação com o padrão ouro da citologia de aspiração por agulha fina.
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PURPOSE: Ultrasound is most effective study for evaluating thyroid nodules. In this review, we discuss that sonographic findings to differentiate benign from malignant nodules and suggest recommendations for indications of fine needle aspiration biopsy and thyroid nodule management. METHODS: Sonographic scans of 206 thyroid nodules in 164 patients were candidated for this study. We evaluated sonographic findings by shape, calcification, margin, and echogenicity, retrospectively. Sonographic findings that suggested malignancy included microcalcifications, a speculated margin, marked hypoechogenicity and a shape that was taller than wide. The final diagnosis of lesion as benign (n=180) or malignant (n=26) was confirmed by fine needle aspiration biopsy and follow-up (>6 months). We demonstrated the difference of the sensitivity, specificity, positive predictive value, negative predictive value and accuracy. RESULTS: Of 206 thyroid nodules, 26 were malignant. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy based on our sonographic classification method were 84.6%, 73.9%, 31.9%, 97.0% and 75.2%. CONCLUSION: Sonography can be helpful for making the differentiation between and malignant nodules. So, when well trained surgeon find thyroid nodules on sonography, we can make correct diagnosis of malignant nodules.
Subject(s)
Humans , Biopsy , Biopsy, Fine-Needle , Classification , Diagnosis , Follow-Up Studies , Methods , Retrospective Studies , Sensitivity and Specificity , Thyroid Gland , Thyroid Nodule , UltrasonographyABSTRACT
PURPOSE: To analyze the synthetically created sonographic features of thyroid nodules, we present here a new scoring system for the sonographic features that are suggestive of malignant thyroid nodules. We also evaluated the accuracy and clinical significance of this system. MATERIALS AND METHODS: In this study, we included 725 thyroid nodules of 405 patients that were pathologically proven by USG-guided percutaneous fine-needle aspiration biopsy (FNAB) or surgery. Two radiologists analyzed the sonographic features according to the internal content, margin, echogenecity, shape and calcification. We scored from 0 point to 2 point for each feature, and then we calculated the total scores and classified them as three groups according to the total score such as low risk (0-3), intermediate risk (4-6) or high risk (7-10). We demonstrated the difference of the frequency and the positive predictive value among the three groups by using the Chi-square test (p<0.005). RESULTS: For 725 nodules, 654 (90.2%) were benign and 71 (9.8%) were malignant. For 589 nodules classified as low risk, 10 (1.7%) were malignant. For 102 nodules classified as intermediate risk, 32 (31.4%) were malignant. For 34 nodules classified as high risk, 29 (85.8%) were malignant. There was a statistically significant difference in the frequency and positive predictive value of malignancy among the three groups (p<0.001). CONCLUSION: There was a statistically significant difference in the frequency and positive predictive value of malignancy among the three groups for the new scoring system presented in this study to analyze the synthetically sonographic features of thyroid nodules. So, we think that sonography can be helpful for making the differentiation between benign and malignant nodules. When we find thyroid nodules on sonography, we can reduce the unnecessary FNAB and we can diagnose malignant nodules at an earlier stage.