11 research outputs found
Near-Infrared Visual Differentiation in Normal and Abnormal Breast Using Hemoglobin Concentrations
Introduction: Near-infrared (NIR) optical imaging is a non-ionizing modality that is emerging as a diagnostic/prognostic tool for breast cancer according to NIR differentiation of hemoglobin (Hb)concentration.Methods: The transmission values of LED-sourced light at 625 nm were measured by power meter to evaluate the optical properties of Hb in breast phantom containing major and minor vessels. For the simulation of blood variations in cancerous breast condition, we prepared 2 concentrations of pre-menopausal Hb and 4 concentrations of post-menopausal Hb and, for comparison with normal tissue, one concentration of Hb injected inside the phantom’s vessels. Imaging procedure on the phantom was also conducted by LED source and CCD camera. The images from the experiments were compared with the results obtained from the images analyzed by MATLAB software. Finally, mammography of phantom including various concentration of Hb was prepared.Results: The transmitting intensities of NIR in blood containing 1, 2 and 4 concentrations of Hb in the major vessels were 52.83 ± 2.85, 43.00 ± 3.11 and 31.17 ± 2.27 μW, respectively, and in minor vessels containing similar Hb concentrations were 73.50 ± 2.43, 60.08 ± 5.09 and 42.42 ± 4.86 μW, respectively. The gray-scale levels on the major vessel were about 96, 124, 162 and on the minor vessel about 72, 100, 130 measured for 1, 2 and 4 Hb concentrations, respectively. The sensitivity and specificity of NIR imaging differentiation were 97.4% and 91.3%, respectively.Conclusion: Significant differences in transmitting intensity, optical imaging as well as software analysis of images were observed for 1, 2 and 4 concentrations of Hb in major and minor breast phantom vessels. Differentiation capability of minor vessels was higher than major vessels for Hb concentrations. Despite a good detection for location of vessels by mammography, it could not show differences between vessels with various concentrations. However, NIR optical imaging demonstrated a good image contrast for showing vessels in terms of concentration. This study recommends NIR optical imaging for prescreening breast cancer due to its potential for early diagnosis
Synthesis and characterization of nano Bi2O3 for radiology shield
Objective (s): Recently, the use of nanoparticles in medicine has increased for radiation protection purpose. So the aim of this study was application of nano Bi2O3 in prepared shield for dose reduction during medical imaging.Materials and Methods: Nano Bi2O3 shield with 90% silicon and 10% nano Bi2O3 was prepared and dosimetry test was down in radiology by PTW DIADOS E dosimeter.Results: The mean dose without using nano Bi2O3 shields were 421 µGy, 733 µGy and 1110 µGy for 60, 80 and 100 kVp , respectively. After using 0.5 mm thickness of nano Bi2O3 shield dose reduction in 60, 80 and 100 kVp was 42%, 35% and 31%. A comparison between increasing energy from 60 to 100 kVp and dose reduction showed a significant reverse effect.Conclusion: The results indicate that the new shields containing nano Bi2O3 particles have a high X-rays attenuation ability but the attenuation property of the shields was decreased by the increasing of the energy. Based on the results, this new shield can help social health and decline the radiation risk
Bismuth-silicon and bismuth-polyurethane composite shields for breast protection in chest computed tomography examinations
The article aims at constructing protective composite shields for breasts in chest computed tomography and investigating the effects of applying these new bismuth composites on dose and image quality. Polyurethane and silicon with 5% of bismuth were fabricated as a protective shield. At first, their efficiency in attenuating the X-ray beam was investigated by calculating the total attenuation coefficients at diagnostic energy range. Then, a physical chest phantom was scanned without and with these shields at tube voltage of 120 kVp, and image parameters together with dose values were studied. The results showed that these two shields have great effects on attenuating the X-ray beam, especially for lower energies (<40 kV), and in average, the attenuation coefficients of bismuth-polyurethane composite are higher in this energy range. The maximum relative differences between the average Hounsfield units (HUs) and noises of images without and with shield for both composites in 13 regions of interest were 4.5% and 15.7%, respectively. Moreover, primary investigation confirmed the ability of both shields (especially polyurethane-bismuth composite) in dose reduction. Comparing these two composites regarding the amount of dose reduction, the changes in HU and noise, and attenuation coefficients in diagnostic energy range, it seems that polyurethane composite is more useful for dose reduction, especially for higher tube voltages
Functional response difference between diabetic/normal cancerous patients to inflammatory cytokines and oxidative stresses after radiotherapy
Diabetes, which is considered as a chronic metabolic disorder leads to an increase in inflammatory cytokines and oxidative stresses. Studies have shown several functional differences in the oxidative stress and inflammatory cytokines responses in diabetic/normal cancerous patients candidate for radiotherapy. Also, radiotherapy as a cancer treatment modality is known as a carcinogen due to oxidative damage via generation of reactive oxygen metabolites and also causing inflammation of the tissue by increasing the inflammatory cytokines. Therefore, the consequence of diabetes on oxidative stress and increased inflammatory factors and synergistic effects of radiotherapy on these factors cause complications in diabetics undergoing radiotherapy. It is considered as one of the most interesting objectives to control inflammation and oxidative stress in these patients. This review aims to concentrate on the influence of factors such as MPO, MDA, IL-1β, and TNF-α in diabetic patients by emphasizing the effects related to radiation-induced toxicity and inflammation by proposing therapeutic approaches which could be helpful in reduction of the complications
Evaluation of Patients’ Exposure during Angiography and Angioplasty Procedures in the Angiography Department of Shahid Madani Hospital in Tabriz
Introduction: Coronary angiography and angioplasty procedures lead to significant radiation exposure of patients. In the current study, the average radiation dose to patients during angiography in the Angiography Department of Shahid-Madani Hospital was determined. Materials and Methods: An image intensifier based angiography unit (Philips BH 3000) was used for angiography procedures. The accuracy of the internal dosimeter was verified. Dose-area products (DAP) of patients (236 cases) during fluoroscopy and cine acquisition were recorded. Analyzing the data, the average radiation doses to patients for angiography and angioplasty and also for fluoroscopy and cine acquisition were determined. Additionally, the average fluoroscopy time for all patients was estimated. Results: The average DAPs of 23.7 and 91.5 Gycm2 were estimated for angiography and angioplasty respectively. Patient doses including fluoroscopy, cine acquisition and the total dose for angiography were 2, 7.7 and 3.8 times lower than angioplasty procedures respectively. Average fluoroscopy time was 1.9 times lower for angiography compared to angioplasty. Discussion and Conclusion: Fluoroscopy time and patient dose during fluoroscopy were in good agreement with other studies. However, the dose to patients during angioplasty was higher compared to other reports. To reduce patient dose in angioplasty procedures, the use of the lowest available frame rate, smallest field size and retraining of operators and technologists are recommended