Extraosseous accumulation of TECHNETIUM-99M-METHYL diphosphonate (99MTc-MDP) on bone scan is not common. This phenomenon is often attributed to abnormality of calcium metabolism and has been reported in a variety of conditions including metabolic diseases and malignancies. A five years old boy is presented here, who was admitted to the pediatric emergency suffering from fatigue, respiratory symptoms, weight loss, intermittent fevers, anorexia, nausea and vomiting, edema of legs and abdominal distension for one month. The initial laboratory analysis revealed hypercalcemia. The patient was referred for whole body bone scan with suspicion of malignancy and bone metastasis. The bone scan revealed highly increased radiotracer uptake in both lungs in the perfusion and blood pool phases. Delayed images also showed increased activity in lungs and gastric wall. The skeleton was not seen clearly. Bone marrow aspiration was done and established the diagnosis of ALL. The patient deceased due to respiratory failure 20 days later.Diffuse lung uptake in this patient was consistent with respiratory failure and poor prognosis. It is reported that bone scan may be useful for assessment of the extent of metastatic calcification and may establish suitable management to prevent organ failure.

Introduction: This article as the first clinical prospective study was conducted to use of Tc-IgG as compared with autologous Tc-RBC in gated blood pool ventriculography. Moreover, two objectives were followed: (a) assess the feasibility of this radiotracer in routine practice; (b) appraise its in vivo steadiness over time by measurement of organs activity ratios and the image quality.Methods: the study population included 12 patients who referred for evaluation of liver hemangioma or infection process. Six patients underwent gated planar blood pool (GPBP) acquisition using Tc-RBC and remaining 6 cases underwent GPBP with Tc-IgG. Additionally, to evaluate the activity ratios in different organs, ROIs were manually drawn over the LV, RV, right lung, left lung, aorta, liver and spleen on the static anterior datasets in 20 minute (early) and also delayed (180 minutes) post injection of Tc-RBC and Tc-IgG.Ratios of activity between the early and delayed images were compared for each ROI.Results: The mean time of acquisition following injection of each radiotracer (RBC; 75.83±11.75 minute Vs IgG; 80.00±7.09 minute) was not different [p value>0.05]. Observer 1 and 2 were classified good quality for both radiotracers in all participants. The mean ejection fraction (EF) of patients with Tc-RBC and Tc-IgG wan not significantly different (59.00±7.64 % vs.58.33±16.03 %) [P value>0.05]. The ratio of LV to crescent background in GBP was not statistically difference between two agents (RBC; 2.55±0.99 Vs IgG; 2.11±0.78) The mean activity of LV and RV to backgrounds ratios in patients with Tc-IgG was more (although nonsignificant) relative to cases radiolabeled with in vitro Tc-RBC on early and delayed views (P>0.05). In addition, the relevant constancy of biodistribution of both radiotracers over time was also compared in the organs activities between the early and delayed studies.Conclusion: This data showed that the use of Tc-IgG in cardiac blood pool studies might led to comparable images as Tc-RBC. Therefore, 99MTc-IgG, readily accessible and needing a single injection, might be an attractive alternative to Tc-RBC for the estimation of LV function, especially in subjects with poor vein quality or busy departments.

Quercetin as a natural product scavenges superoxide anion radicals and hydroxyl radicals with potent antioxidant activity, these properties are mainly due to polyphenolic and several hydroxyl groups of quercetin.In this study, we have prepared and evaluated TECHNETIUM-99M (99MTc) -labeled quercetin as a potential radical scavenging radiotracer. A 99MTc-quercetin complex was prepared using quercetin, SnCl2 and Na99MTcO4 in a buffered solution over 30 minutes. The participation coefficient was measured in octanol and queues solutions. The stability was determined in phosphate buffered saline and serum. The biodistribution in normal mice was evaluated at 0.5, 2, 6 and 24 h post-injection. The radiochemical purity (>99%) was determined by thin layer chromatography (TLC) in normal saline solution as the mobile phase. It has a log P of 0.204. It was mainly cleared by the kidneys and showed negligible brain uptake at four time points measured post-injection. The pharmacological properties of quercetin, mainly its free radical scavenging, may potentially cat as a radiopharmaceutical agent for radical-targeted imaging of tissue with high levels of reactive oxygen species.