1990 Volume 51 Issue 7 Pages 1370-1379
We analysed ultrasonographic findings of ninety lesions (55 carcinomas and 35 benign tumors) of 78 patientswith thyroid diseases with nodular lesions retrospectively.
Ultrasonic findings could be classified into three types; cyst-forming type, solid tumor type and only acoustic shadow type. The cyst-forming type was found in 3.6% of carcinomas while in 37.1% of benign tumors. The carcinomas of solid tumor type tended to appear as non-uniform internal echogenicity and irregular marginal sign, but benign tumors appearing as uniform internal echogenicity and regular marginal sign in ultrasonography. The non-uniform internal echogenicity depended on pin point and/or spot-like echo-rich shadow in all the carcinomas and the half of the benign tumors. Moreover, the echo-rich shadow was observed in all cases having calcification, in 80.5% of cases only having hyalinized connective tissues, or in 29.4% of cases without the former described features. Only acoustic shadow type was found in 18.2% of the carcinomas while in 5.7% of benign tumors.
In order to differentiate malignant tumors from benign ones by echography, the significance of detailed examination of its marginal sign and internal echogenicity should be emphasized, excluding lesions showing only acoustic shadow.
