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: During computed tomography (CT) examinations, the presence of radiation material undoubtedly has a certain impact on patients, particularly children, who are more susceptible to radiation. Consequently, finding ways to minimize radiation Dosage and mitigate radiation-related risks while enhancing the quality and accuracy of CT scans has become a crucial concern for medical professionals in CT equipment manufacturing companies and radiology departments to contemplate. Objectives: This study aimed to explore the feasibility of Low dose and Low Contrast Medium combined with Low fLow rate scanning in CT angiography (CTA) of children's liver. Patients and Methods: A total of 59 children who visited our department for liver vascular CT scans between April 2021 and December 2022 were prospectively selected and randomly divided into 2 groups: the experimental group and the control group. The experimental group consisted of 28 children who received an injection of 80 kV, automatic tube current, Low Contrast dose (1.5 mL/kg), and Low fLow rate of 20 s. The control group included 31 children who were injected with 100 kV, automatic tube current, Contrast agent dose (2 mL/kg), and fLow rate of 16 s. The objective and subjective image quality, radiation dose, and iodine intake in the arterial, portal, and venous phases were compared between the 2 groups. Results: During the arterial, portal, and venous phases, the experimental group exhibited Lower signal-to-noise ratio (SNR) and Contrast-to-noise ratio (CNR) compared to the control group (P < 0.05). However, there was no significant difference in subjective quality scores between the 2 groups (P > 0.05). The effective dose (ED), volume CT dose index (CTDIvol), and dose-length product (DLP) of the experimental group were Lower than those of the control group (P < 0.05). Additionally, the iodine intake in the experimental group was Lower than that in the control group (P < 0.05). Conclusion: In the examination of hepatic vascular CTA in children, the use of a 3-Low scanning technique can effectively decrease radiation and Contrast agents while ensuring sufficient image quality for accurate clinical diagnosis.

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

Introduction: Vancomycin is a wide useable antibiotic against gram-positive bacteria species in different clinical setting particularly in hemodialysis patients. Objectives: The present study aimed to assess the serum level of vancomycin before and after hemodialysis. Patients and Methods: This cross-sectional study was performed on patients who were hospitalized and medicated by vancomycin with the loading dose of 1000 mg folLowed by the maintenance dose of 500 mg after each dialysis session every other day. All patients were dialyzed with a Low-flux dialyzer membrane. Half an hour before and immediately after dialysis, 2 mL blood sample was taken and stored at-20° C until assaying the level of vancomycin. Results: The average reduction in the serum level of vancomycin was totally 17. 65 ± 1. 69%. The mean reduction in the serum level of vancomycin was significantly higher in the patients aged higher than 60 years, as compared to other ones. But the level of drug was independent to gender or body mass index. Conclusion: Using Low-flux dialyzer membranes, the average reduction in the serum level of vancomycin is expected to be in the range of 12. 43% to 21. 56% that age was directly associated with the average reduction of the level of vancomycin. Therefore, adjusting and monitoring the serum level of drug in old ages even in the cases of using Low-flux dialyzer membranes is recommended.

In order to avoid using cytotoxic drugs and to minimize prednisolone side effects in frequent relapsing or steroid-dependent idiopathic nephrotic syndrome, 35 patients, 3 to 15 (mean= 8.1) years of age, were studied. While in remission for at least 6 weeks, the dose of prednisolone was reduced to 0.1-0.37 (mean= 0.23) mg/kg/day as a single dose for 12 to 72 (mean= 27.6) months. It was folLowed by a tapering method, with gradual increase in the interval instead of decrease in the dose for about 10 to 12 months, and about 18.4 months folLow-up without treatment. About 54.3% of the patients had no relapse during the treatment period and the relapse rate per patient per year was 3.94 during the preceding 12 months before the study, 0.51 during treatment (p<0.001) and 0.23 after discontinuation of the drug. Each relapse was treated by a standard dose of prednisolone for 2 months and then the Low dose regimen was resumed. The patients tolerated the drug well with minimal side effects. It is concluded that long term, Low-dose daily prednisolone therapy folLowed by gradual increase in the interval is a safe, well-tolerated and effective method of maintaining prolonged remission in most children with frequent relapsing idiopathic nephrotic syndrome.

Purpose: To evaluate the pattern-reversal visual evoked potential (PRVEP) in LowContrast, spatial frequencies in time, frequency, and time-frequency domains. Methods: PRVEP was performed in 31 normal eyes, according to the International Society of Electrophysiology of Vision (ISCEV) protocol. Test stimuli had checkerboard of 5% Contrast with spatial frequencies of 1, 2, and 4 cycles per degree (cpd). For each VEP waveform, the time domain (TD) analysis, Fast Fourier Transform(FFT), and discrete wavelet transform (DWT) were performed using MATLAB software. The VEP component changes as a function of spatial frequency (SF) were compared among time, frequency, and time– frequency dimensions. Results: As a consequence of increased SF, a significant attenuation of the P100 amplitude and prolongation of P100 latency were seen, while there was no significant difference in frequency components. In the wavelet domain, an increase in SF at a Contrast level of 5% enhanced DWT coefficients. However, this increase had no meaningful effect on the 7P descriptor. Conclusion: At a Low Contrast level of 5%, SF-dependent changes in PRVEP parameters can be better identified with the TD and DWT approaches compared to the Fourier approach. However, specific visual processing may be seen with the wavelet transform.