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Background: The effect of gadolinium-based contrast agents (GBCA) on the spinal cord is not established, especially in patients with diabetes mellitus., Purpose: To investigate neuronal and myelin loss in the spinal cord when employing macrocyclic ionic Gadoterate Meglumine (Gd-DOTA) and non-ionic Gadobuterol (Gd-BT-DO3A) GBCA in rats with and without diabetes mellitus., Materials and Methods: This study was performed between November 2018 and February 2020. Sixty young Sprague Dawley white rats (n = 6/group) were given injections of two macrocyclic GBCA: 0.5 mmol/ml Gd-DOTA and 1 mmol/ml Gd-BT-DO3A, using volumes based of the recommended doses (0.1 ml and 0.2 ml) for 42 days in both healthy and diabetic rats. Control groups received saline injections. Morphological assessment of spinal cord tissues was performed on three spinal segments. Neuronal counts in the ventral horns and myelin sparing percentage in the white matter were determined and compared in each group employing one-way ANOVA and Dunnett test for each category followed by three-way factorial analysis., Results: Low neuronal count and myelin percentage-area were obtained in groups receiving 0.2 ml Gd-DOTA (p = .001;p = .002;p < .001 neurons; and p < .001;p = .007;p = .001 myelin %) and Gd-BT-DO3A (p = .01;p = .048;p = .006 neurons; p < .001;p = .01;p = .001 myelin %). Similarly, neuronal loss was seen in diabetics receiving low volume-injection (0.1 ml) of Gd-DOTA (p = .04;p = .03;p = .42), Gd-BT-DO3A (p = .002;p = .007;p = .01); or high volume-injection (0.2 ml) of Gd-DOTA (p = .001;p = .003;p = .01) or Gd-BT-DO3A (p < .001,p = .002;p = .002), with associated decrease in myelin sparing for each category with low dose Gd-DOTA (p < .001, p = .001; p. = 09),Gd-BT-DO3A (p = .003;p = .003;p = .007); or the higher dose counterparts of Gd-DOTA (p < .001; p < .00; p = .001) and Gd-BT-DO3A (p < .001, p < .001, p < .001). Damage was observed using the standard dose (equivalent of 0.1 mmol/kg for rats) of Gd-DOTA (0.2 ml) but not that of Gd-BT-DO3A (0.1 ml) in healthy rats., Conclusion: Multiple high-volume injections of gadoterate meglumine and gadobuterol are associated with neuronal and myelin injury in the spinal cord, more so in rats with diabetes mellitus., (Copyright © 2024. Published by Elsevier Inc.)

Giant multilocular cystadenomas of the prostate or seminal vesicles are rarely reported in literature. We present a case of a 76-year-old male presenting with lower urinary tract symptoms initially perceived as symptoms of benign prostatic hyperplasia. The patient was investigated by employing a multimodality imaging approach of the prostate that included ultrasound, computed tomography, and magnetic resonance imaging, which resulted in an incidental finding of large multiloculated benign cysts originating from the prostate, confirmed by pathological study. This case report highlights the multimodality imaging approach in the detection and diagnosis of this rare disease.

Models in evolutionary game theory traditionally assume symmetric interactions in homogeneous environments. Here, we consider populations evolving in a heterogeneous environment, which consists of patches of different qualities that are occupied by one individual each. The fitness of individuals is not only determined by interactions with others but also by environmental quality. This heterogeneity results in asymmetric interactions where the characteristics of the interaction may depend on an individual's location. Interestingly, in non-varying heterogeneous environments, the long-term dynamics are the same as for symmetric interactions in an average, homogeneous environment. However, introducing environmental feedback between an individual's strategy and the quality of its patch results in rich eco-evolutionary dynamics. Thus, individuals act as ecosystem engineers. The nature of the feedback and the rate of ecological changes can relax or aggravate social dilemmas and promote persistent periodic oscillations of strategy abundance and environmental quality., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To investigate the knowledge and practice of computed tomography (CT) radiographers working in Jordan., Materials and Methods: This Institutional Review Board (IRB) approved study disseminated a questionnaire via social media and recruited 54 Jordanian CT radiographers. The questionnaire comprised 36 questions divided into four sections: demographics; an evaluation of knowledge regarding CT exposure; modifications to CT exposure for paediatric patients; dose units and diagnostic reference levels (DRLs). Descriptive and inferential statistics including Chi-square tests, Mann-Whitney U tests, independent samples t-tests and Kruskal-Wallis H tests were employed. Statistical significance was considered below p < 0.05., Results: The 54 participants had various qualifications, with the majority holding a Bachelor's degree (n = 35, 64.8%) and the rest holding a Diploma (n = 19, 35.2%). In order to pass the questionnaire, participants needed to score 13 correct answers. The overall number of radiographers who correctly passed the questionnaire was 48 (88.9%). None of the participants correctly stated all the DRL values for chest, abdomen and brain CT. However, four out of 54 respondents (7.4%) knew the chest DRL value, three (5.6%) participants correctly estimated the abdominal DRL value but only two (3.7%) knew the DRL for the brain., Conclusion: Good general knowledge was found amongst radiographers regarding the relationship of each exposure parameter to the image quality and patient dose. However, there was poor knowledge of diagnostic reference levels and the order of the organ radiation sensitivity. The need for CT radiographers to undertake further education that focuses on radiation exposure in CT is highlighted., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the impact of patient centering and radiation dose during intracranial computed tomography (ICT) on quantitative and qualitative image quality., Materials and Methods: A total of 500 consecutive patients who underwent ICT were retrospectively reviewed using a 128-slice CT scanner (Definition AS+, Siemens, Germany). Patients were subjected in equal numbers to one of two positioning protocols: group A, poorly centered; and group B involved accurate centering before imaging. Gray-white matter (GWM) conspicuity, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) in each group were calculated. Qualitative image quality in terms of GWM differentiation, distinctness of posterior fossa contents, and overall diagnostic acceptability were evaluated by 2 neuroradiologists. The dose length product, CNR, SNR, and noise were measured between each group and data generated were compared using Mann-Whitney U nonparametric statistics. Visual grading characteristic and Kappa analyses were performed., Results: The mean noise index was significantly lower in group B (2.61 ± 0.29) compared with A (2.66 ± 0.21; P < .02). The mean attenuation of GWM, SNR, and CNR in the frontal lobe (A, 1:0.77, 0.84, 8.70 ± 1.36; and B, 1:0.65, 0.85, 15.32 ± 1.21; P < .02), occipital lobe (A, 1:1.10, 1.18, 10.79±2.11; and B, 1:0.94, 0.64, 14.41 ± 3.09; P < .04), and cerebellum (A, 1:0.79, 0.90, 12.56 ± 4.08; and B, 1:0.82, 0.87, 14.07 ± 2.28; P < .04) were significantly higher in group B compared with A, while the globus pallidus, caudate nucleus, and optic track in the basal ganglia demonstrated no difference in each group (P > .05). Mean dose length product demonstrated no significance between each group (A, 1312.03 ± 133.92; B, 1298.11 ± 130.61). The qualitative analyses demonstrated significant increases in visual grading characteristic for each reader (P < .02) and interobserver agreement was significantly increased in protocol B (k = 0.81) compared with A (k = 0.62)., Conclusions: Correct patient centering increases the CNR and SNR in both GWM in the left and right hemispheres of the brain during ICT., (Copyright © 2016 Canadian Association of Medical Radiation Technologists. Published by Elsevier Inc. All rights reserved.)

Multifocal basal ganglia T2-weighted hypointensities are believed to arise mainly from mineralization in and around penetrating arteries and perivascular spaces within gray and white matter structures. Recently, it has been proposed that these hypointensities can serve as a biomarker for small-vessel disease and aging in magnetic resonance imaging when using T2-weighted sequences. With advances in digital coil technology and parameter applications, there has been an increase in image quality and faster examination times. However, artifacts related to higher-field strengths (3.0 T) are reducing image quality. This case report demonstrates reduced focal hypointensities in the basal ganglia by using concentric rectangular blades rotated around the k-space origin to reduce artifacts at 3.0 T., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Cirsoid aneurysms of the scalp are a rare abnormality with severe cosmetic deformity and possibly of severe hemorrhage. They present as a diagnostic and management challenge, but evaluation with multidetector computed tomography is useful in the diagnosis and treatment planning of these clinically complex disorders of the extracranial circulation. We present a case report of a 38-year-old New Caledonian male who had a large pulsatile mass in his scalp, which had progressively increased in size since the age of 17 years. The clinical and imaging features are outlined, in addition to treatment and prognosis., (Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.)

Background: Increased speeds of computed tomography (CT) acquisition and concomitant increased intravenous (IV) bolus injection rates have placed patients at greater risk of contrast extravasation., Purpose: To assess the efficacy of the MEDRAD XDS extravasation detector by recording the incidence of contrast extravasation in high-risk patients during CT angiography., Material and Methods: We prospectively collected data on 25 adults ages 45 to 85 years (mean=65 years), all of whom were considered to be at high risk of having a contrast extravasation. All patients underwent CT angiography with power-injected IV contrast injection introduced via an antecubital venous line. Details recorded included patient age and weight, contrast volume, flow rate, maximum injector pressure, image quality, and extravasation incidence and volume. The size of the most commonly used cannula was 20 gauge and the flow rates ranged from 4.0 to 6 mL/second., Results: The XDS device alerted the clinicians to five episodes of extravasation. These were identified at an early stage of the injection with no more than 8 mL of contrast material having been introduced., Conclusion: The utility of this device has been demonstrated and its employment should reduce extravasated contrast volumes with minimum discomfort to high-risk patients., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Contrast medium (CM) administration for multidetector computed tomography angiography (CTA) requires using a power injector. Power injectors deliver viscous CM at different flow rates up to a maximum pressure of 300 lb per square inch (psi), provide features that benefit patient safety, improve arterial and parenchymal opacification, and allow flexible and complex injection protocols to be administered. The use of power injectors not only includes contrast but also saline, which is primarily responsible for reducing the overall volume of contrast administration while maintaining peak vessel opacification over a longer duration during the CTA acquisition. CTA faces multiple challenges with advanced scanner hardware. There is an increased need to inject small volumes of CM at fast injection rates over a short duration. This technical overview is to increase the understanding of parameters that influence optimal contrast enhancement and bolus geometry, and to enable the user to modify and optimize scanner and contrast protocols., (Copyright © 2011 Elsevier Inc. All rights reserved.)