Design and construction of a variable resolution cone-beam small animal mini-CT prototype for in vivo studies

Abstract

We present the conceptual design and construction of a mini x-ray computed tomography (mini-CT) scanner designed and built for in vivo small-animal imaging. The imaging system includes an x-ray tube with 0.5 mm focal spot size and a flat panel detector that provides an active area of 41 × 41 cm 2 with 200 µm × 200 µm pixel size. The scanner, designed based on the rotating sample idea, features variable imaging magnification and fieldof-view (FOV). To this end, the detector and x-ray tube are mounted on linear motion systems, such that the object to detector or object to x-ray source distance can be easily changed. The variable magnification enables to acquire images at different spatial resolution depending on the size of the object being imaged. This design provides a trade-off between the scanner's FOV and imaging spatial resolution in which small objects are imaged at relatively high spatial resolution as smaller FOVs are required. Conversely, larger objects can also be imaged as the scanner's FOV is adjustable at the expense of spatial resolution degradation. The scanner's FOV varies from 43 cm down to 9 cm (in diameter) with a spatial resolution improving from 3.9 cycle/mm up to 14.4 cycle/mm, respectively. This mini-CT scanner is a self-standing versatile imager suitable for various preclinical imaging applications.

Estimation of optimized timely system matrix with improved image quality in iterative reconstruction algorithm: A simulation study

“…The presented algorithm is able to improve the time limitation of the iterative algorithm as well as may be used for image reconstruction of industrial CT scans. Despite of medical CT scans which usually have the same geometrical specifications, the industrial CTs are constructed with various geometrical specifications because the industrial facilities need to use CTs with different dimensions along with different detector sizes and types [31,32]. The presented method may help designers, who have to survey and investigate the effects of different geometrical specifications on the quality of the images and achieve the optimized design in a short time.…”

Comparison of the X-ray tube spectrum measurement using BGO, NaI, LYSO, and HPGe detectors in a preclinical mini-CT scanner: Monte Carlo simulation and practical experiment

“…There have been always interests in designing detectors with the highest possible sensitivity (to detect very low activity concentration) and high spatial resolution (to localize the spatial distribution of the activity concentration). Normally, there is a fundamental tradeoff between improvements in sensitivity and spatial resolution of a detector, wherein strategies such as reducing the field of view (FOV) or modifying the distances between detector, object, and X-ray source (variable magnification) have been adopted to find an optimal compromise between these two key parameters (Lohrabian et al, 2019;Arabi et al, 2015;Arabi, KAMALIASL, Aghamiri;Kamali-Asl et al, 2009;Arabi et al, 2011;Sanaat et al, 2020).…”

Quantitative Analysis of Image Quality in Low-Dose Computed Tomography Imaging for COVID-19 Patients

“…[ 7 8 ] CT imaging is an accurate and noninvasive method for detecting abnormalities, including tumors, bone fractures, and cardiovascular diseases. [ 9 10 11 12 ] Recently, an extended range of clinical studies has been performed on the potentials of CT imaging for the diagnosis and management of patients with COVID-19 disease. These studies, in fact, continue to fully identify the underlying COVID-19 features in CT images.…”