Advanced equine diagnostics – developments in computed tomography

Advancement in veterinary imaging technologies to assess pathology in the horses has been greatly improved since the development of computed tomography in the 1970s. These technical innovations have enabled faster acquisition times, lower patient doses of radiation and easier care of the patient during scanning. A wide range of computed tomography scanners are now available to the veterinary market, from companies providing second hand refurbished scanners, to those tailoring computed tomography scanners to the veterinary market. In turn, this makes the price of purchase, or rental, much more feasible to the industry. The financial implications of purchasing a scanner need to be reviewed to ensure viability, as well as identifying maintenance costs, space, specialist staffing and case load. However, even with access to advanced imaging devices such as computed tomography, imaging the equine patient comes with its own complexities and limitations. Owing to their size and anatomy, passing the relevant structures through the gantry can be difficult in itself, often requiring the administration of general anaesthetic to acquire suitable images, which comes with its own set of risks and additional costs. Therefore, there is an ongoing need to further develop the skills and abilities needed for standing computed tomography.

Emerging techniques in atherosclerosis imaging

Atherosclerosis is a chronic immunomodulated disease that affects multiple vascular beds and results in a significant worldwide disease burden. Conventional imaging modalities focus on the morphological features of atherosclerotic disease such as the degree of stenosis caused by a lesion. Modern CT, MR and positron emission tomography scanners have seen significant improvements in the rapidity of image acquisition and spatial resolution. This has increased the scope for the clinical application of these modalities. Multimodality imaging can improve cardiovascular risk prediction by informing on the constituency and metabolic processes within the vessel wall. Specific disease processes can be targeted using novel biological tracers and smart contrast agents. These approaches have the potential to inform clinicians of the metabolic state of atherosclerotic plaque. This review will provide an overview of current imaging techniques for the imaging of atherosclerosis and how various modalities can provide information that enhances the depiction of basic morphology. This publication is the reprint with Russian translation from original: Syed MBJ, Fletcher AJ, Forsythe RO, Kaczynski J, Newby DE, Dweck MR, et al. Emerging techniques in atherosclerosis imaging. Br J Radiol 2019; 92: 20180309. DOI: https://doi.org/10.1259/bjr.20180309

Assessing the Status of Quality Control Parameters of Four Computed Tomography Scanners in Ibadan

Background: Quality control (QC) of computed tomography (CT) scanners is important to evaluate succinctly quality image and radiation dose obtainable in a clinical environment. The aim of this study was to evaluate the quality of images generated by CT scanners used at some diagnostic facilities in Ibadan, Nigeria. Materials and Methods: A cross sectional design was employed in this study, four centers were studied, one government hospital and three private hospitals. The head CT phantom was used to verify the accomplishment of the CT scanners performance to the international quality requirements. Regions of interest were selected at the center of the image and at the periphery to obtain results for the CT number for water test, uniformity test, noise, and artifact test. Results: The mean CT number for water across the centers ranged from –0.12 HU to –2.2 HU which were within ±3 HU recommended by the equipment manufacturer. Values of standard deviation of the mean CT number ranged from 2.41 to 5.77 HU which to a little extent exceeded the set ±5 HU tolerance range. Similarly, the presence of streak artifact was observed in the images obtained at one center. Conclusion: Two out of the four computed tomography scanners assessed passed the four tests performed. Noise and artifact were the problem observed at centers B and C respectively. There was however no likelihood of periodic performance of these basic quality control tests at two of the centers in this study. Adequate records of quality control data should be kept regularly to allow in-depth analysis of failure rates of different tests, changes occurring during equipment lifetime and comparisons among CT scanners.

Computer Tomography Scanners in Brazil (2010-2017)

The aim of this study was to verify the availability of CT scanners in the Brazilian territory, for the period 2010 to 2017, comparing the results with those indicated by the Brazilian legislation (Ordinance GM/MS Nº. 1101, 2002; Resolution RE Nº. 1016, 2006). The second objective is a review of the most recent national data; publishing official statistics on the number of CT scanners installed in Brazil and compares them with the data available from other countries, obtained in international publications. Estimates of the CT scanners distribution are made by the utilization rate, which means the number of scans performed per thousand inhabitants multiplied by the total population of the region, where as the maximum coverage area of scanner in a radius of 75 km or 100,000 inhabitants. The results suggest greater concentration of equipment in the Southeast, South and Midwest area, private and public sectors, and a number of scans far above the recommended, throughout the Brazilian territory. The number of CT scanners currently in operation in Brazil would have the ability to cater to a population up to 110,7 % higher than the current population, and their geographical distribution within the country largely unknown.

Simulation Study for Designing a Dedicated Cardiac TOF-PET System

The development of dedicated positron emission tomography scanners is an active area of research, especially aiming at the improvement of lesion detection and in support of cancer treatment and management. Recently, dedicated Positron Emission Tomography (PET) systems with different configurations for specific organs have been developed for improving detection effectiveness. Open geometries are always subject to distortion and artifacts in the reconstructed images. Therefore, the aim of this work is to determine the optimal geometry for a novel cardiac PET system that will be developed by our team, and determine the time resolution needed to achieve reasonable image quality for the chosen geometry. The proposed geometries consist of 36 modules. These modules are arranged in two sets of two plates, each one with different configurations. We performed Monte Carlo simulations with different TOF resolutions, in order to test the image quality improvement in each case. Our results show, as expected, that increasing TOF resolution reduces distortion and artifact effects. We can conclude that a TOF resolution of the order of 200 ps is needed to reduce the artifacts, to acceptable levels, generated in the simulated cardiac-PET open geometries.