Characterization of benign and malignant tissues of the thyroid gland. An ultrasonic approach using RF waveform analysis and pattern recognition

Ultrasound imaging in diffuse thyroid disorders of children

The diagnosis of diffuse thyroid disorders in children is based mainly on hormone and antibody determinations and a cytologic sample taken by aspiration biopsy. The cytologic sample is not always obtainable in small children or when the thyroid gland is not enlarged. Thyroid antibodies lead to diagnosis only in a proportion of cases. Gamma imaging is not recommended in children because of the radiation risk. The aim of this study was to demonstrate that ultrasound imaging can detect diffuse thyroid disorders in children. Ultrasound images were abnormal in 92% of all subjects; they were abnormal in 97% of cases with thyroiditis and in most cases ultrasound was diagnostic. With antibody determinations, only 60% of the cases of thyroiditis could be diagnosed. Ultrasound imaging--a risk-free method--should be included in the diagnostic investigation of thyroid disorders.

Sonographic tissue characterisation in thyroid gland diagnosis. A correlation between sonography and histology

Punch biopsy was carried out in 32 cases in which thyroid gland changes were sonographically classified as being of homogeneously normal or of homogeneously low echogenicity. Mean follicle lumen size was morphometrically determined from the histological sections. This produced a significant, positive correlation between echogenicity and follicle size. The mean follicle lumen diameter in so-called echonormal structures was 67 microns (SD +/- 23 microns), and 25 microns (SD +/- 8 microns) in low-echogenic lesions. Thus normal echogenicity represented a normofollicular or macrofollicular structure, while a low echogenicity pattern indicated a microfollicular or solid tissue structure. The structure of thyroid carcinomas is not homogeneously normofollicular or macrofollicular; in exceptional cases they are such only focally. Therefore the significance of these findings lies in the exclusion of malignancy in the event of homogeneously normal echogenicity.