AN INCREASE IN THE AMOUNT OF TISSUE AND CYTOLOGICAL MATERIAL WHEN PERFORMING VACUUM FINE NEEDLE ASPIRATION BIOPSY UNDER THE CONTROL OF ULTRASOUND NAVIGATION IN FOCAL THYROID PATHOLOGY

Thyroid diseases rank the second among endocrine pathology, at this, thyroid cancer is the most common among endocrine tumors. Ultrasound examination has contributed to more frequent detection of thyroid pathology and remains an effective method for the differential diagnosis of focal thyroid pathology, and the use of multiparametric ultrasound makes it possible to identify a malignant process at its early stage of development. Despite the introduction of multiparametric ultrasound, fine needle aspiration biopsy remains the "gold" standard in the differential diagnosis of benign and malignant changes in the thyroid gland. However, a large range of informative value, sensitivity and obtaining a false negative result when using this method promoted the search of solutions for modifying biopsy performing with an increase in the amount of cytological material and reducing the risks of complications. the purpose of the study is to determine the effectiveness of using v-FNAB compared to the FNAB performed with a LUER syringe. on the basis of diagnostic and minimally invasive technologies department at Clinical Hospital No. 1 of the town of Smolensk in the period from April to December 2021, 48 vacuum fine needle aspiration biopsies were performed without using modifications, and from January to April 2022, 51 vacuum fine needle aspiration biopsies were performed using a modified technique. All the results obtained were correlated with the results of 273 fine needle aspiration biopsies using a 20 ml 3LUER syringe performed in the period from 2019 to 2021. Sampling of cytological material when performing vacuum fine needle aspiration biopsy is much easier, since when using a vacuum, a negative pressure vacuum in the syringe is formed with the help of the apparatus and is maintained at a constant level. in addition, when performing a vacuum fine needle aspiration biopsy with a modified syringe, there was a decrease in the amount of cytological material lost, which in the original version was absorbed into the tissue membrane. This is especially important in hypervascular focal formations, as a result, the number of Bethesda 3 conclusions decreases from 16.6% to 5.9%. Thus, v-FNAB facilitates performing the manipulation due to no need to perform aspiration using a syringe piston, thereby reducing the number of uncontrolled needle movements during sampling the cytological material, which affects the diagnostic value of the examination. Due to the high level of negative pressure when performing v-FNAB, the amount of cytological material obtained increases, which also affects obtaining an informative conclusion. the ability to select the level of negative pressure in the syringe depending on the data of multiparametric ultrasound examination makes it possible to individualize the procedure.