Lactic acidosis (LA) secondary to metformin administration is a rare incident with a very high mortality rate (≥ 50%). Hypoxia has been suggested to contribute to metformin-associated lactic acidosis (MALA) in 90% of patients developing this condition. In susceptible patients such as those with renal insufficiency, the level of plasma metformin is increased particularly after exposure to iodinated CONTRAST media (ICM). One major concern in patients with renal insufficiency is to adjust the metformin dose based on the renal functional capacity prior to ICM examination. In this review, we assessed metformin tolerable threshold in diabetic patients with renal failure. We also reviewed metformin withdrawal criteria in patients with chronic kidney disease (CKD) exposed to intravenous ICM during angiography. Our results indicated that in patients with insufficient renal function (i. e. 30< estimated glomerular filtration rate(eGFR) <60 and 30

Background: The CONTRAST MEDIUM (CM) in CT pulmonary angiography may induce adverse effects to patients, and higher CM is associated with higher rates of CONTRAST-induced-nephropathy and mortality. Reduction of CM dosage through improvement of examination techniques may help reduce the occurrence of CM-induced adverse effects and healthcare costs. Objectives: To determine the optimal monochromatic energy levels in dual-energy spectral CT pulmonary angiography (CTPA) with low CONTRAST dosage. Patients and Methods: Thirty patients with suspected pulmonary embolism (PE) underwent dual-energy spectral CTPA with low radiation and low CONTRAST doses with scanning protocol of GSI-36 with 260 mA, and 25 mL CONTRAST (350 mgI/mL) with 4. 0ml/s injection speed. The monochromatic images from 60-80 keV (interval 5 keV) were reconstructed using a 50% adaptive statistical iterative reconstruction (50% ASiR) algorithm at 1. 25 mm slice thickness. The CT attenuation and standard deviation (SD) values of the main, right, left, right lower and left lower pulmonary arteries and the back muscle at the same level were measured on 60-80 keV images, and signal-to-noise ratio (SNR) and CONTRAST-to-noise ratio (CNR) were calculated and analyzed. The subjective image quality was evaluated by two experienced radiologists using a 5-level scoring method independently. Measurements were analyzed using IBM SPSS Statistics for Windows, version 25. 0. (Armonk, NY: IBM Corp. ). Results: CT attenuation values of the pulmonary arteries decreased with the increase of energy level in five-energy groups, with values greater than 300 HU at 60 keV-70 keV energies. The 65 keV image had the highest SNR, CNR and lowest SD, with significant differences compared with those of other image sets (P < 0. 05). The subjective quality scores for the 65 keV image was judged to be the highest by the two radiologists, but it was not significantly different from 60 keV and 70 keV (all P > 0. 05). Conclusion: The 65 keV monochromatic images provided the highest SNR, CNR and subjective scores with the lowest image noise in dual-energy spectral CTPA with low CONTRAST dosage.

BACKGROUND: Alveolar pattern of the lung field is usually caused by several lung involvements such as edema, hemorrhage and pneumonia, but differentiation using radiography is usually impossible. Objectives: Evaluation of HU and lung pattern of pneumonia in dogs using CT-scan technique and confirmation by CT assisted FNA as a safe diagnostic procedure. Methods: In this study, 10 dogs with respiratory distress suspected for pneumonia were selected and radiography and CBC were used for evaluation of lung pattern and cytology. Before and after CONTRAST MEDIUM injection, CT-scans of the lung field were achieved. Finally, in transverse CT sections, FNA of involved lung lobes was taken for cytologic evaluation. After the confirmation of pneumonia, CT scans were reevaluated with more attention and pulmonary pattern was described and HU of involved regions was measured. Results: In all of the patients, ventral region of the lungs, especially cranial and middle lung lobes were involved and the involvement of the left lungs was prominent. The mean HU of the unhealthy lung parenchyma before CONTRAST MEDIUM study was between 31 and 39, and after CONTRAST study was between 46 and 70. It means the HU has been significantly increased. Also, the CONTRAST of the involved lung regions was increased which helped to differentiate the unhealthy lung tissue from the adjacent soft tissues. Hematology tests in all of the patients were representative of infection. Conclusions: Both CT-scan and CT assisted FNA from the lung are beneficial and practical methods for the diagnosis of pulmonary disorders such as pneumonia

By identifying the effect of any parameter such as distance, attenuation and scattering on the Line Spread Function (LSF), one can compensate the quantitative and qualitative destructive effect of such parameters by disconsolation method. Using a 99mTC line source, this study was performed on a single head ADAC SPECT system operating in planar mode. Variation of FWTM and FWHM and LSFs as a function of source to collimator distance in air, source depth in scattering MEDIUM (water) and the combined effects of distance and depth of the source in scattering MEDIUM were investigated. The equations of spatial resolution (FWHM) with the above mentioned conditions were found to R1=0.07481+4.0862mm for I≥100mm for and Rd=0.0102 d+10.962mm for d≥0mm and Rh=0.2512h-14.609mm for h≥100mm respectively. Where R1, Rd and Rh are spatial resolution (FWHM). I and h are the source to collimator distances in air and scattering MEDIUM respectively and d is the source to collimator distance in the scattering MEDIUM eliminating distance effect on FWHM. These variations were found to be linear having different slopes. The results showed that increasing source to collimator distance in air degrades the spatial resolution considerably, i.e. an increase of 10 cm degrades the spatial resolution by 54%. In this case the variation in FWTM is almost similar to FWHM. By increasing the source depth only in scattering MEDIUM (Eliminating the effect of source distance) no noticeable change on spatial resolution is seen, but due to accumulation of scattered photons under both wings of the LSF, the increase in FWTM is more intense than FWHM. This phenomena causes the broadening of sharp edges which in turn leads to loss of CONTRAST and errors in determining the size of lesions and the uptake of activity in ROI.

The administration of radio CONTRAST media may lead to kidney injury, known as CONTRAST-induced nephropathy, which is reversible in most cases, but its development may be associated with adverse outcomes. This review article provides recommendations for the prevention of CONTRAST nephropathy.

CONTRAST MEDIUM is used daily for accurate and effective diagnostic procedures. They are often necessary to provide an exact diagnosis and are almost safe and effective when used correctly. However CONTRAST media can sometimes be life-threatening especially in elderly, since the elderly suffer from several problems. Aging is frequently accompanied by chronic diseases like chronic renal failure, comorbidity, frailty and disability. Therefore, it is important to know how reactions to CONTRAST agents manifest and how to manage them immediately. Decreased kidney functions are sometimes seen after intravenous CONTRAST media injection therefore radiologists should monitor all stages of the CONTRAST injection. Accordingly, the medical team should have information on the complications, prevention and care of the patients under CONTRAST media.

Ultrasonic suspension can be used for a wide range of particles due to its independence from the material and properties of the material, and has a high potential for the transfer and manipulation of particles in a controlled manner. The main purpose of this paper is to use a new method based on ultrasonic waves, for suspension and non-contact separation of particles from the desired environment. Using this method, called acoustophoretic, the target particle is first injected into the fluid MEDIUM and then it is suspended and separated. The environment chosen for suspension and separation is water. The reason for this choice is the novelty of the suspension and separation in this environment due to the higher viscosity and speed of sound of water than air and the proximity of this environment for water purification, separation of water in crude oil and microfluidic scale separation of platelets from blood. The acoustic force must be greater than the resultant of the gravitational and buoyancy force so that it can overcome it and suspend the particle. In order to increase this force it is necessary to increase the acoustic pressure, which is not feasible due to the low frequency in macro scale (20 kHz) and increasing the power consumption of the transducer causes cavitation that prevents the suspension of particles. At this stage, the initial velocity of the particles in the simulation and practical mode was given as 0. 4 m / s and the results showed that the largest difference in velocity between the particles with low and high volume was 12. 5% ​​in the simulation and 10% in the experiment, Therefore, the larger the particle, the more force it feels and the faster it gets. The largest difference between simulation and experimental test was 8% therefore, experimental tests confirmed the design accuracy and also the simulation results.

Introduction: Considering the unwanted exposure to organs in the path of the beam, 4-field (4F) and subsequently, Intensity-modulated-radiation-therapy (IMRT), is known as the standard mode of treatment of carcinoma cervix. It is routine practice to inject intravenous CONTRAST during simulation scan which elopes after that from the patient body. Therefore, the impact of CONTRAST media should be investigated for radiation dose calculations. Material and Methods: An indigenously made phantom, named as ‘, original CONTRAST (OC)’, , was used with dimensions 15 x 15 x 30 cm3 . A sleeve was given to place the ionization chamber at the isocentre of the planning target volume (PTV) inside the cylindrical vial of iodinized CONTRAST. Similarly, a virtual phantom was created with similar dimensions in the presence and absence of CONTRAST media, called as ‘, virtual CONTRAST (VC)’,and ‘, virtual without CONTRAST (VWC)’,phantom. Plans were generated with photon energies (6MV/10MV/15MV/6FFF/10FFF) using 4F and IMRT technique. Plans were evaluated for PTV (D99%, D10%, Dmean) and Bladder & Rectum (V30Gy, V10Gy). Normal-tissue-integral-dose (NTID) and total-monitor-units (TMU) were also evaluated. Results: D99% of the PTV was comparable in VC and VWC phantoms but was decreased for OC phantom. Similarly, D10% was reportedly higher as 54. 03 Gy (4F, 6 MV), 54. 71 Gy (4F, 15 MV), 55. 78 Gy (4F, 6 FFF) and 57. 64 Gy (4F, 10 FFF) for OC phantom. D30% of the bladder and also the NTID was lesser for IMRT cases in all the selected phantoms. Additionally, 4F has shown lesser spillage with 6MV/15 MV photon beam energies in OC phantom. The ‘, total monitor units (TMU)’,required for IMRT plans were significantly higher. Conclusion: The CONTRAST material under-estimates the planned dose yet has an insignificant influence on the dose calculation. Therefore, unnecessary exposure of dual scans should be avoided the use of 6MV and IMRT technique should be continued in the clinics.