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Radium-223 chloride is an alpha emitter radiopharmaceutical which recently has been used for treatment of bone metastases. Absorbed and equivalent doses of RaCl were studied using MCNPX Monte Carlo code in a phantom consisted of bone marrow, bone and soft tissue. Sm-EDTMP as a beta emitter was also simulated for comparison with RaCl. Results show that by injection of 100 µCi RaCl against 70 mCi Sm-EDTMP to a 70 kg adult man, equivalent dose of metastatic bone can be increased about six times without significant increase in delivered dose to healthy tissues. These results demonstrated acceptable agreement with experimental data. [ABSTRACT FROM AUTHOR]

Hydroxyapatite was applied as a carrier adsorbing Y ions for Y-HA colloid production. The radiopharmaceutical colloid was prepared by adding an acidic solution of YCl to HA suspension in saline solution. Effective parameters on labeling of Y-HA were evaluated. Adsorption and cation-exchange properties were studied using inductively coupled plasma elemental analysis and N adsorption-desorption isotherm method. Radionuclidic purity was over 99.9 %. Labeling yield and radiochemical purity were >99 %. Radiochemical purity was evaluated also in human albumin for 7 days at 37 °C. Biodistribution studies have shown complete retention of injected radioactivity at the administration site up to 72 h. [ABSTRACT FROM AUTHOR]

Neutron irradiation of a natural Sm target is performed to produce Sm. Ion-exchange chromatography is used to separate Sm from Eu radionuclides produced in the process. To prepare a target, SmO powder is dissolved in 0.2 ml of HNO in a quartz vial. Samarium is deposited onto the vial walls by passing nitrogen gas at 120°C. The prepared samarium target is encapsulated in aluminum foil and irradiated in a 5-MW reactor in 5 × 10 n cm s flux. The irradiated target is dissolved in 1 M HCl, and the produced radioisotopes are determined with an HPGe nuclear detector. Finally Sm is separated from Eu radionuclides with Sm recovery yield of more than 66% and purity better than 99.8%. [ABSTRACT FROM AUTHOR]

Purpose: We have developed an algorithm for real-time detection and complete correction of the patient motion effects during single photon emission computed tomography. The algorithm is based on a linear prediction filter (LPC).Materials and Methods: The new prediction of projection data algorithm (PPDA) detects most motions-such as those of the head, legs, and hands-using comparison of the predicted and measured frame data. When the data acquisition for a specific frame is completed, the accuracy of the acquired data is evaluated by the PPDA. If patient motion is detected, the scanning procedure is stopped. After the patient rests in his or her true position, data acquisition is repeated only for the corrupted frame and the scanning procedure is continued.Results: Various experimental data were used to validate the motion detection algorithm; on the whole, the proposed method was tested with approximately 100 test cases. The PPDA shows promising results.Conclusion: Using the PPDA enables us to prevent the scanner from collecting disturbed data during the scan and replaces them with motion-free data by real-time rescanning for the corrupted frames. As a result, the effects of patient motion is corrected in real time. [ABSTRACT FROM AUTHOR]