RESUMO
Background: in this study, human absorbed dose of a newly introduced bone imaging agent, 68Ga-[4-[[[bis[phosphonomethyl]]carbamoyl]methyl]-7,10-bis [carboxymethyl]-1,4,7,10-tetraazacyclododec-1-yl] acetic acid [68Ga-BPAMD], was estimated based on the rats data
Materials and Methods: 68Ga was obtained from the 68Ge/68Ga generator and it's radionuclidic and radiochemical purities were investigated. 68Ga-BPAMD complex was prepared at optimal conditions and the radiochemical purity was studied using instant thin layer chromatography [ITLC] method. The final preparation was injected to the normal rats and the biodistribution of the complex was followed up to 120 min post injection. The accumulated activity for animal organs was calculated. Finally, the human absorbed dose of the complexes was estimated by RADAR Method
Results: 68Ga-BPAMD complex was prepared in high radiochemical purity [>99%, ITLC] at optimal conditions. The biodistribution of the complex demonstrated that the main remained radioactivity would considerably accumulate into the bones. The results showed the highest amounts of absorbed dose on the bone surface [0.253 mGy/MBq] and in the bone marrow [0.250 mGy/MBq], while the other organs would receive an insignificant absorbed dose after injection of the 68Ga-BPAMD complex
Conclusion: the comparison of dosimetric results for 68Ga-BPAMD with other complexes shows this complex is a safer agent for bone scanning. This property as well as other characteristics such as the high resolution images of the positron emission tomography [PET] scanning and the availability of 68Ga in the form of 68Ge/68Ga generator, make this complex as a suitable agent for PET bone imaging
RESUMO
Considering the influence of geographical, genetic and ethnic factors on the prevalence of thyroid pathological lesions, this study was performed to assess the prevalence of pathological lesions in thyroid autopsic samples obtained from adult cadavers of Isfahan Forensic Medical Center. In this study, 202 thyroid glands from cadavers with no evidence of thyroid diseases, removed during autopsies at Isfahan Forensic Medicine Center, were analyzed. After gross studies, thyroid glands were fixed in 5% formalin for 72 hrs, and then 3-6 sections were obtained from each gland. Tissue sections were microscopically studied by two pathologists for histopathological lesions. Among 202 thyroid glands [removed from 159 males and 43 females], 131[64.85%] were histopathologically normal, and goiter [nodular, and diffuse], Hashimoto's thyroiditis, lymphocytic thyroiditis, follicular adenoma and papillary carcinoma were observed in 41 [20.3%], 10 [4.95%], 12 [5.94%], 2 [1.49%] and 12 [5.94%] of the thyroid glands, respectively. Twenty-six glands [12.23%] had nodules sized = 1cm, which included 7 cases of occult papillary carcinoma [papillary micro carcinoma] and the prevalence was significantly different by sex [P<0.05]. Clinically-normal thyroid glands may contain major pathological lesions when they are microscopically studied. Considering the high prevalence of thyroid malignancy and occult carcinoma in Isfahan County compared to other parts of the world, more attention should be paid even to the minor findings during clinical examination of thyroid gland