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This chapter overviews palliative treatment modalities for patients with bone metastases. In the introduction section, the origin of bone metastases and complication of metastatic patients have been discussed. Then, the main body explains treatment modalities including pain relievers, bisphosphonates, surgery, external beam radiotherapy, and targeted radionuclide therapy for pain palliation of patients with bone metastases.

Purpose: Radiopharmaceutical Therapy (RPT) is one of the effective methods for pain palliation of bone metastases. Bone marrow is a critical organ in bone structure whose absorbed dose should be kept below a certain threshold. The purpose of this study was to calculate and compare absorbed doses of bone-seeking radiopharmaceuticals used in the palliative treatment of bone metastases. Materials and Methods: In this study, the GATE Monte Carlo code was used to simulate a femur bone, which consists of bone marrow, endosteal layer, bone, and soft tissue phantom model. Absorbed doses of the 153Sm-EDTMP, 89SrCl2, 177Lu-EDTMP, 188Re-HEDP, and 223RaCl2 radiopharmaceuticals were calculated in the femur phantom compartments. Results: bone absorbed doses per disintegration from alpha particles of 223RaCl2 is approximately 24 times higher than absorbed doses from beta particles of 89SrCl2. Also, absorbed dose per disintegration from beta particles of 89SrCl2 in the bone is approximately 12, 6 and 1.5 times higher than 177Lu-EDTMP, 153Sm-EDTMP, and 188Re-HEDP, respectively. Moreover, the bone and bone marrow absorbed dose from beta particles of 153Sm-EDTMP is 1.9 times higher than 177Lu-EDTMP. Besides, absorbed dose per disintegration from beta particles of 188Re-HEDP in the bone marrow is approximately 40, 30, 7, and 4 times higher than 223RaCl2, 89SrCl2, 177Lu-EDTMP and 153Sm-EDTMP, respectively. Conclusion: Our results show that 223RaCl2 could be a more efficient radiopharmaceutical for radionuclide therapy of bone metastases. Also, 177Lu-EDTMP, due to low marrow toxicity and comparable bone absorbed dose with 153Sm-EDTMP, can be used for achieving bone pain palliation. Moreover, significantly high bone marrow absorbed dose of 188Re-HEDP should be considered for palliative therapy of metastatic bone patients.

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Introduction: Generally, the benefits of radiological examinations performed on individuals far outweigh their risks; however, this is not true when the radiographic system fails to work properly. Therefore, to avoid such errors, it is crucial to frequently perform Quality Control (QC) checks in an imaging facility. Material and Methods: A total of 11 highly-referred centers out of 62 radiology rooms located in Yazd province were included in this investigation, and QC tests comprising light/radiation field alignment, the accuracy of kilovoltage and exposure time, reproducibility of kilovoltage, exposure time, and output, and linearity of output against exposure time and milliamperage were performed for each equipment. The light and radiation field alignment test were carried out by a quantitative assessment of digital images of a collimator template (PTW-Freiburg, Germany). The measurements were made by a Barracuda package and a Multi-Purpose Detector (MPD). Results: In terms of the light/radiation field alignment check, unit A failed to satisfy the national regulations. Concerning the timer reproducibility, 64% of the units failed to meet the criteria. All of the devices passed the rest of the checks satisfactorily. Conclusion: This study uncovered that most of the radiology rooms in Yazd province are in an adequate situation based on the QC tests; however, more than half of the units do not satisfy the timer reproducibility criteria. Hence, more supervision needs to be directed at these systems by qualified radiation safety officers who are responsible for the protection of the population against ionization radiation.