Sonographic Features of Thyroid Nodule For Predicting Risk of Malignancy

Bhatarai M*, Bhatarai MD*, Basnet S**, Karki BB**, Bajracharya MR**


INTRODUCTION: Thyroid nodules present a challenge in their diagnosis, evaluation and management. Ultrasonography (USG) and Fine Needle aspiration Cytology (FNAC) are initial steps of evaluation of mass whether the nodule is benign or malignant. Although individual USG features may be of limited value, when multiple signs of thyroid malignancy appear in combination it is possible to make an accurate prediction. USG of thyroid nodule can be a useful tool to predict the malignancy of thyroid gland.

METHOD: This study was aimed to evaluate the validity of USG findings in predicting risk of malignancy in thyroid nodules. USG of including color flow Doppler was performed in 54 cases with clinically palpable thyroid nodule/s in the department of Radiology and Imaging, NAMS (National Academy Of Medical Science), Bir Hospital from July 2007 to June 2008.USG guided fine needle aspiration for cytological examination was followed by USG.

RESULT: USG diagnosed 49(90.7%) cases as benign and 5(9.3%) cases as malignant. The sensitivity, specificity, Positive predictive Values (PPV) and Negative predictive Values ( NPV) of microcalcification in nodule is 80%, 100%, 100% and 90% respectively. Similarly ill-defined margin and regional lymph node had sensitivity (100%), specificity (85.71%), PPV (41.6%), NPV (100%) and sensitivity (80%), specificity (92.1%), PPV (57%), NPV (97.2%).All values are statistically significant.Central vascularity also had sensitivity 100% and significant p value 0.001. The validity of nonechogenicity and solitary nodule was statistically less significant.

CONCLUSION: Sonographic findings of thyroid nodule like presence of micro calcification, ill-defined margin, internal central vascularity and presence of regional lymphadenopathy can be used to predict malignancy of thyroid nodules.

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