For the first time in Lithuania morphometric measurements of thyroid cytological preparations were carried out using fine needle aspiration and an image analysis system. The work presents complex analysis of ultrasonic, cytomorphological, cytomorphometric and histological examination data, their interrelation and informativeness. The work results have showed spectrum of clinical, morphological, morphometric changes and frequency of nodular thyroid at various thyroid diseases. We determined significant changes of nodular thyroid, informativeness and diagnostic value of different examination methods for differentiation of thyroid diseases and diagnosis of thyroid cancer. Early diagnosis of thyroid tumors is being successfully carried out in Lithuania as well as ultrasonic test, radio isotopic scanning, cytomorphological and histological analysis of FNA aspirate. The aim of our study was to determine cytomorphological and cytomorphometric indications of the thyroid nodules using ultrasound and fine needle aspirate and to evaluate their complex value. 1. To evaluate ultrasonic characteristics of nodular thyroid examination. 2. To determine cytomorphological parameters of fine needle aspirate. 3. To establish cytomorphometric indications of nuclei in nodular thyroid epithelium cells and to determine their interrelations (area, perimeter, convex perimeter, min and max axes, shape factor, ovalness, roughness). 4. To determine morphometric changes of thyroid cytological categories. ... [to full text]