Osteopenia and Osteoporosis Screening Detection: Calcaneal Quantitative Ultrasound with and without Calibration Factor Comparison to Gold Standard Dual X-ray Absorptiometry.

BACKGROUND: osteoporosis is a worldwide major health problem that normally diagnosed in advanced stages. So, an early detection at preclinical stage is now an interesting issue. A key factor to early diagnosis the disease is the used of noninvasive bone densitometry. Dual energy x-ray absorptiometry (DXA) is the gold standard techniques for the proposed. However, the high cost, non-widely available and exposed to ionizing radiation are still a drawback of the machine. Therefore, a cheaper, smaller and non-ionizing device such quantitative ultrasound (QUS) is now a favor alternative method, but the possibility of used QUS measurement instead of DXA is still limited due to their uncertainties. So, the aim of our study was to calibrated the QUS with the DXA to allowing the possible to establish a calibration factor (CF) to improve the measured value closer to the standard method. METHODOLOGY: 135 healthy men and women aged 30-88 years were recruited for lumbar spine/femoral neck DXA and calcaneal QUS scanning. The Pearson's correlation between T- and Z-score from the two systems were studied. Moreover, the sensitivity, specificity and percentage of diagnosed accuracy for both with and without CF were calculated. RESULTS: The significant correlation between the two systems showed a positive trajectory in highly correlation (r = 0.784-0.899). Analyses showed a higher sensitivity, specificity and reduced the misdiagnosed rates when applied the CF in QUS values. CONCLUSIONS: QUS results showed a significantly correlated with DXA results for both lumbar spine and femoral neck sites with some percentage differences. These differences can be reduced by applied an individual specific machine CF to improve a QUS results. As identification of high risk of osteopenia and osteoporosis to reduce the demand of DXA propose, using a QUS alternative method can be a reliable that provide a cheaper and lack of ionizing radiation.

Effect of iodinated contrast media on peripheral blood mononuclear cells in terms of cell viability, cell cycle and oxidative stress in an in vitro system.

Iodine contrast agents are essential for diagnostic purposes in radiology and have significant medical benefits. However, they pose a risk of causing allergic reactions or adverse cellular effects. In this study, we examine the in vitro effects of iodine contrast agents (Iopamiro 370, Ultravist 370, Visipaque 320, and Optiray 350) on cellular functions of human peripheral blood mononuclear. The findings reveal that a concentration of 50 mgI/ml of iodine contrast agents causes a 50% reduction in cell viability, but lower concentrations of 2.5, 5.0, and 10.0 mgI/ml do not affect the cell cycle. Furthermore, the contrast agents decrease oxidative stress levels in cells. In conclusion, this study demonstrates that iodine contrast agents can be used safely in appropriate concentrations for diagnostic purposes without affecting the cell cycle and preventing oxidative stress on normal cells. The insights gained from this study could aid in the development of diagnostic contrast agents in the future of medicine.

Determination of scattered radiation dose for radiological staff during portable chest examinations of COVID-19 patients.

The COVID-19 pandemic has resulted in a large increase in the number of patients admitted to hospitals. Radiological technologists (RTs) are often required to perform portable chest X-ray radiography on these patients. Normally, when performing a portable X-ray, radiation protection equipment is critical as it reduces the scatter radiation dose to hospital workers. However, during the pandemic, the use of a lead shield caused a heavy weight burden on workers who were responsible for a large number of patients. This study aimed to investigate scatter radiation doses received at various distances, directions, and positions. Radiation measurements were performed using the PBU-60 whole body phantom to determine scatter radiation doses at 100-200 cm and eight different angles around the phantom. The tests were conducted with and without lead shielding. Additionally, the doses were compared using the paired t test (p < 0.005) to determine suitable positions for workers who did not wear lead protection that adhered to radiation safety requirements. Scatter radiation doses of all 40 tests showed a highest and lowest value of 1285.5 nGy at 100 cm in the anteroposterior (AP) semi upright position and 134.7 nGy at 200 cm in the prone position, respectively. Correlation analysis between the dosimeter measurement and calculated inverse square law showed good correlation, with an R2 value of 0.99. Without lead shielding, RTs must stay at a distance greater than 200 cm from patients for both vertical and horizontal beams to minimize scatter exposure. This would allow for an alternative way of performing portable chest radiography for COVID-19 patients without requiring lead shielding.

Radiation Protection Device Composite of Epoxy Resin and Iodine Contrast Media for Low-Dose Radiation Protection in Diagnostic Radiology.

Radiation protection in radiology is important because radiation may cause harm to the human body. The equipment for radiation protection is essential to ensure safe operations. Currently, there is widespread research on lead-free radiation shielding material. The aim of this research was to study lead-free material containing epoxy and iodine contrast media that was easy to form, low in cost, and environmentally friendly. The results showed that 2-cm material thickness with a concentration of 20% iodine had the greatest properties of radiation attenuate in the peak potential applied at technique 60-120 kVp, but the structure and strength of the shielding materials were decreased in accordance with increasing concentrations of iodine contrast media. It can be concluded that the lead-free epoxy radiation-shielding materials are able to absorb radiation at energy levels of 60-120 kVp. However, with improvement on homogeneity in the future, it could be used as a refractory shielding material in the radiology department.

A phamtom study: In vivo rectal dosimetry of high dose rate brachytherapy in cervical cancer.

The purpose of this study was to perform in-vivo dosimetry using a diode rectal dosimeter in phantom and compare the dose delivered to the rectum between the dose measured by the diode dosimeter and the dose calculated by the treatment planning system in cervical cancer. The PTW T9112 diode detector calibrations were performed to find the correction factor. Then the calibrated diode detector was used to measure the radiation dose received in the rectum area in the in-house pelvic phantom. An Iridium-192 source was loaded into the phantom with 7 Gy, the measurements were 3 times per treatment plan, with 15 total plans studied. The average cumulative charge (nC) of each plan was converted to the absorbed dose (mGy) for comparison with the treatment planning system. Finally, to test the hypothesis that an absorbed dose from the detector and the treatment planning system were not significantly different, dependent t-test statistical analysis was applied with p-value <0.05. For distance and direction correction factors, we found that the factors were approximately 1 at 5 cm and 180°. The percentage differences of radiation dose between the diode dosimeter and the treatment planning system were between -3.3 and 4.1%. Statistical analysis revealed that the doses from the detector and the treatment planning system were not statistically significant different. The comparison showed that the percent difference between diode dosimeter and treatment planning system was acceptable to perform the in vivo dosimetry in brachytherapy. Therefore, the diode detector may be a suitable candidate for a treatment verification system in cervical cancer brachytherapy to prevent the dose delivery errors that directly affect the prognosis and may cause complications for the patient.