Cercetări în patologia tiroidiană folosind tehnici neconvenționale de înaltă rezoluție cu fascicule laser / Research in thyroid pathology using unconventional high-resolution laser beam techniques

The research topic addresses a sensitive topic of thyroid pathology, namely the development of a histopathological diagnosis that is as accurate as possible for the benign and malignant encapsulated thyroid nodules. The increasing incidence and/or overdiagnosis of thyroid carcinomas both worldwide and in Romania requires finding a new method that complements the traditional optical microscopic examination to correctly diagnose thyroid malignancies, only by studying the distribution and structural changes of capsular collagen, using unconventional high resolution laser beam techniques: Confocal Laser Scanning Microscopy (C;SU;, Two-photon Excited Fluorescence (TPEF) Microscopy and Second Harmonic Generation (SHG) tvlicroscopy which has proven to be the most useful, which represents the purpose of the thesis. The obtained results arise from the interdisciplinary collaboration and the consistent application of a working standard in all the experiments from this thesis. From images with thyroid nodules capsule-and thyroid gland, the quantitative parameters were computed at pixel level and image level, which allowed the analysis of the collagen composition in the capsules. Statistically relevant results were obtained by comparing the structural changes and-the distribution of collagen fibers: a more “ordered” malignant capsule, with more well-directed and organized longer elongated collagen fibers, compared to the more wavy benign capsule. These results suggest, for the first time in literature, that some thyroid tumor nodules can be differentiated by simply studying their capsule, without the need for tumor cell morphology assessment, an indispensable element in the histopathological diagnosis of certain encapsulated nodular tumor lesions so far.