Software-Based Analysis of the Taller-Than-Wide Feature of High-Risk Thyroid Nodules.

ABSTRACT

BACKGROUND: Shape is one of the most important features in the diagnosis of malignant thyroid nodules. This characteristic has been described qualitatively, but only shapes that appear markedly different can be easily differentiated at first interpretation. This study sought to clarify whether software-based shape indexes are useful for the detection of thyroid cancers. METHODS: In the final analysis, 200 participants with 231 pathologically proven nodules participated in the study. Ultrasound features were assessed by clinicians. The tumor contour was auto-defined, and shape indexes were calculated using commercial software. RESULTS: Of the 231 nodules, 134 were benign and 97 were malignant. The presence of taller-than-wide (TTW) dimensions differed significantly between the benign and malignant thyroid tumors. Designation of TTW assessed by the software had a higher kappa value and proportional agreement than TTW assessed by clinicians. Disagreement between the clinician and software in designating nodules as TTW occurred for 28 nodules. The presence of other ultrasonic characteristics and small differences in the height and width measurements were causes for the incorrect interpretation of the TTW feature. CONCLUSION: The proposed software-based quantitative analysis of tumor shape seems to be promising as an important advance compared with conventional TTW features evaluated by operators because it allows for a more reliable and consistent distinction and is less influenced by other ultrasonic features.