The Accuracy of High Resolution Ultrasonography in the Diangnosis of Thyroid Carcinoma in Solitary Thyroid Nodule

Abstract

The Accuracy of High Resolution Ultrasonography in the Diangnosis of Thyroid Carcinoma in Solitary Thyroid Nodule

Linda                 Chandrachamnong          MD*

Praween          Kanchanapitak                 MD**

*Department of Radiology, BMA Medical College and Vajira Hospital

**Department of Pathology, Faculty of Medicine, Srinakharinwirot University.

Objective: To study the accuracy of high resolution ultrasonogtaphy in the diagnosis of thyroid carcionoma in solitary thyroid nodule.

Study design: Diagnostic test.

Setting: Department of Radiology, BMA Medical College and Vajira Hospital.

Subjects: One hundred and fifteen patients with solitary thyroid nodule confirmed by high resolution ultrasonography treated at Bangkok Metropolitan Administration Medical College And Vajira Hospital from January 1998 to December 2001.

Methods: All patients were investigated by high resolution ultrasonography before surgery. Ultrasonographic diagnoses using echo pattern of thyroid nodules were compared with pathology.

Main outcome measures: Prevalence, sensitivity, specificity accuracy, positive predictive value, negative predictive value, posttest likelihood if test negative and likelihood ratio.

Results: The prevalence of malignancy in solitary thyroid module was 24/115 or 20.9%. All of the patients with malignancy were female. Sensitivity. Specificity accuracy, positive predictive value and negative predictive value were 79.2%, 52.7%, 58.3%, 30.6% and 90.6% respectively. Posttest likelihood if test negative was  9.4% and likelihood ratio was 1.7/1.

Conclusion: Using echo pattern by high resolution sonography in solitary thyroid nodule does not have high specificity and accuracy enough for diagnosis of thyroid carcinoma.

Key words: thyroid, solitary nodule, carcinoma, ultrasonography

Vajira Med J 2002 ; 46 : 105 - 113