A eficácia da cintilografía de tireóide na avaliação de nódulos

Abstract

INTRODUCTION: The thyroid is an endocrine gland that plays a very important role in the development of the organism. This "H" or "U" shaped gland is located in the median plane of the neck. The thyroid nodules are one of the forms of presentation of the diseases that affect this gland, their appearance is quite frequent. Radiopharmaceuticals are marked substances that, after being injected to the patient, aim to map the structure, tissue or organ and allow visualizing the functioning or detecting abnormalities such as pathologies. Technetium-99m has been used worldwide for presenting a series of advantages, such as a short half-life (six hours), short retention in the gland, no emission of beta radiation, produces images with good quality in scintillation chambers, besides having a low cost and is readily available. OBJECTIVE: To evaluate the importance of thyroid scintigraphy for the study of nodules, and as specific objectives to appreciate the scintigraphy performed with technetium-99m in comparison to other radioisotopes and evaluation methods. Characterize the main nodules that are related to the gland and describe the methods used to perform the scintigraphy. METHODOLOGY: The study was carried out through an integrative literature review. The consultations were carried out in the following databases: SCIELO (Scientific Eletronic Library Oline), PUBMED, PERIODICOS (Portal.periódicos.Capes), Google Scholar and specialized academic journals with publications between 2002 and 2020. After going through the inclusion criteria and exclusion. 18 articles were found, of which 9 were read in full and later discussed. RESULTS: Technetium-99m was considered as the best option for scintigraphy and thyroid uptake studies, as it has positive characteristics such as: simplicity and reproducibility of application methodologies, low dosimetry, more availability and low cost. It stands out for emitting Gamma radiation and having a very short half-life. The ability to associate with various tissue markers makes it the most important radioisotope in scintigraphy exams. CONCLUSION: With the diagnostic imaging exams currently available, the appearance of nodules in the thyroid is much more common than imagined, but its uncertain clinical evolution calls for a more in-depth assessment to rule out complications. The simplicity and reproducibility of technetium-99m scintigraphy and the additional advantages of low dosimetry, availability and low cost make it the best option for scintigraphy and thyroid uptake studies.