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Background/Aim. The major one among the procedures for evaluating changes in the thyroid nodules is fine needle aspiration biopsy (FNAB). Thyroid scintigraphy is commonly used in diagnostic algoritham of nodules. Less than 5% of examined nodules show to be malignant. Scintigraphically, nodules could be classified as functional and nonfunctional. It is estimated that the risk of malignacy in nonfunctional nodules ranges from 8% to 25% and more. Aspiration punction provides 100% specific and positive predictive value. The aim of the study was to establish the distribution of cytological findings in nonfunctioning thyroid nodules. Methods. The prospective study enrolled 112 patients, 104 women and 8 men, submitted to thyroid scintigraphy for known thyroid nodule disorder. Scintigraphy was performed about half an hour after iv administration of 74 MBq of sodium-pertehnetate. A pin hole collimator was used. Scintigrams were visually evaluated, and absence of radiopharmaceutic in a nodule was estimated as nonfunctional one. Such nodules were afterwards subjected to FNAB and material obtained was cytologically analyzed. Results. In our patients nonfunctioning nodules comprised tissue of colloid struma, thyroid cyst, regular thyroid tissue, follicular lesion, oxiphillic lesion, papillary carcinoma tissue and tissue of lymphocytic thyroiditis. The most frequent cytological finding were colloid cysts (52%). A total of 70% were female nodules. Five citological findings were histopathologically analyzed. Conclusion. Cytological finding of nonfunctional nodules determines of the decision on radical therapy, and our preliminary results imply the need of FNAB routine use in nuclear medicine practice.

Background. Static renal scintigraphy with 99mTc-DMSA is a sensitive method for evaluation of any reduction of cortical mass function. There is not enough reliable references in the literature on scintigraphic reports in terms of objectivity and standardization. The aim of this paper was to assess the differences in interpretation of routine renal scintigraphic findings by nuclear medicine specialists from various institutions (interobserver variability). Methods. Both interobserver variability and agreement in the interpretation were evaluated in two groups. Six observers from four different institutions (group A), and three observers from the same institution (group B) interpreted independently 60 static renal scintigraphy findings obtained by analogous imaging using x-ray films in four standard projections. Using at least two options, seven parameters of renal scintigraphy protocols were analyzed: size (1), uptake (2), outlines (3), scars (4), focal changes (5), relative function (6), and conclusions (7). Results. The interpretations of scintigraphic findings were in accordance in items 1 to 7 within the group A: 62, 42.5, 45, 9, 47, 52, and 34 percent respectively, and within the group B: 72, 55, 59, 22, 62, 60, and 41 percent, respectively. The conformity was more significant in the findings observed in group B as opposed to group A, which was statistically highly significant, especially for the category of scars (p

Objective Tc-99m-p-aminohippuric acid (PAH) is a new radiopharmaceutical rapidly secreted by the kidneys in a manner consistent with tubular secretion. A comparative study of renal scintigraphy and clearance with Tc-99m-PAH, diethylene triamine pentaacetic acid (DTPA) and mercaptoacetyltriglycine (MAG(3)) was performed. Methods (TC)-T-99m-PAH was prepared from a lyophilized kit by addition of sodium pertechnetate in the presence of DTPA. Ten healthy individuals were injected with 110 MBq of Tc-99m-PAH. A dynamic study was repeated with Tc-99m-DTPA and Tc-99m-MAG(3) several days later, after a 1-day interval. Clearance measurements were performed in five individuals. Results The mean values of time-to-peak activity (T-max) and the time from peak to 50% of peak activity (T-1/2) for Tc-99m-PAH (3.6 +/- 0.9 and 6.9 +/- 2.7 min, respectively) and Tc-99m-MAG, (3.5 +/- 0.8 and 6.8 +/- 2.1 respectively) were significantly lower in comparison with those of Tc-99m-DTPA (4.9 +/- 1.7 and 11.7 +/- 1.9 min, respectively). The mean value of Tc-99m-PAH clearance (186.9 +/- 12.2 ml/min) was significantly lower in comparison with MAG(3) clearance (303.9 +/- 19.5 ml/min) and significantly higher than DTPA clearance (85.0 +/- 24.1 ml/min). Conclusion Our preliminary results indicate the potential usefulness of Tc-99m-PAH for routine renal scintigraphy. Owing to its fast kinetics, excretion and high-quality images, it could be a suitable for Tc-99m-DTPA. Tc-99m-PAH clearance values, however, were significantly lower than those of MAG(3), and could not be used for the estimation of renal plasma flow. Nucl Med Commun 30:76-81 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams and Wilkins.

In contemporary nuclear medicine, alpha, pure beta or beta-gamma emitters are used for targeted therapy. Use of pure and combined alpha/beta emitters in oncology, endocrinology, rheumatology and, a short while ago, interventional cardiology, has refined as an important alternative to more common therapeutic regimens. Two radioisotopes of rhenium, rhenium-186 and rhenium-188, are of particular interest. PRODUCTION OF RHENIUM-186 AND RHENIUM-188: Rhenium-186 is routinely produced in nuclear reactors by direct neutron activation of metallic rhenium enriched with 185Re via 185Re(n,) 186Re nuclear reaction. For production of 188Re the target is 186W. 188W is produced by double neutron capture which gives 188Re due to beta decay. Separation of 188Re is performed in generators by column chromatography, extraction or by gel technology. The best results are obtained using chromatographic 188W/188Re generator in which 188W is adsorbed on aluminium. Rhenium-188 is eluted in saline solution.There are several fields of applications of radiopharmaceuticals labeled with 186,188Re. For bone pain palliation the most often used are 186Re-HEDP and 188Re-DMSA. For synovectomy, 186Re-sulphide in kit form is already commercially available. Endovascular radiation therapy is performed by using 188Re-perrhenate or 188Re-MAG3. Labeling of peptides and antibodies with 188Re is also reported. Application of rhenium radiosotopes depends on their specific activity. Rhenium-186,188 of low specific activity can be used only for labeling of particles or diphosphonates. However, labeling of peptides or antibodies can be performed only by using 188Re of high specific activity.188Re is expected to have wide applications after development of a chromatographic 188W/188Re generator. One of the advantages of rhenium is tis chemical similarity with technetium. So technetium analogues labeled with 186,188Re can be developed for several specific applications.

99Tc m -p-aminohippuric acid ( 99 Tc m -PAH) is a new renal radiopharmaceutical prepared from a lyophilized kit by the addition of sodium pertechnetate (Na 99 Tc m O 4 ). Each vial contains PAH, the calcium trisodium salt of diethylenetriamine pentaacetic acid (CaNa 3 DTPA) and stannous chloride (SnCl 2 .2H 2 O) in an inert atmosphere. It is a stable radiopharmaceutical with high radiochemical purity (> 95%). Its protein binding is very similar to that of 131 I-OIH, but it is hydrophilic in character. Animal studies using 99 Tc m -PAH have indicated that it provides renal images of satisfactory qualit y with no external background. Despite its almost identical radiochemical purity and HPLC analysis results to 99 Tc m -DTPA, 99 Tc m -PAH is rapidly secreted by the kidneys in a manner consistent with tubular secretion, as confirmed by rat probenecid studies, whereas 99 Tc m -DTPA is excreted by glomerular filtration. The pharmacokinetic parameters of 99 Tc m -PAH (t 1/2(α) ) = 2.5 min, t 1/2(β) = 41.7 min, Cl = 5.22 ml.min -1 , K et = 5.1 × 10 -4 min -1 ) differ from those of 99 Tc m -DTPA. Evaluation of 99 Tc m -PAH in two human volunteers confirmed its good renal characteristics: rapid disappearance from the vascular system, high uptake in kidneys followed by its very fast elimination, and low residual activity 20 min after its intravenous administration.

The aim of this paper was to compare the value of bone scintigraphy and radiography in the early diagnosis of post-fracture reflex sympathetic dystrophy (RSD). Thirty-seven adult patients with post-fracture RSD (28 in the first and nine in the second clinical stage of RSD), as well as seven patients with fracture but without RSD (control group), were investigated by radiography and bone scintigraphy. All of them were immobilized (duration of immobilization: 4–22 weeks). In 21 persons three phase bone scintigraphy was performed. The best distinction between the control group and the RSD patients was achieved by delayed bone scintigrams. The sensitivity (97%), positive predictive value (97%) and accuracy (95%) of delayed bone scintigraphy were very high compared to the values for radiography, which were 73%, 90% and 70% respectively. Bone scintigraphy also displayed higher specificity (86%) and negative predictive value (86%) than radiography (57% and 29% respectively). In the first clinical stage the difference between the accuracy of bone scintigraphy (97%) and radiography (63%) was greater than for the whole group. In the second stage of RSD the accuracy of bone scintigraphy (86%) and radiography (81%) was similar. Three-phase bone scintigraphy is not necessary for the diagnosis of post-fracture RSD: it is sufficient to perform delayed bone scintigraphy. It is concluded that bone scintigraphy is to be preferred to radiography for the early diagnosis of post-fracture RSD in the first clinical stage. In the second stage the diagnostic capabilities of bone scintigraphy and radiography are more comparable.