Introduction: International Commission on Radiological Protection introduced three basic principles of radiation protection, namely justification, optimization, and dose limit. Medical exposure has no dose limits, and generally, diagnostic reference levels are used as a tool for optimization of patient protection. Material and Methods: Dosimetry was performed on 20 CT scanners located in 14 cit...

Introduction Subject motion in functional magnetic resonance imaging (fMRI) is highly problematic for the detection of responses showing small effect size and/or spatially extent. To mitigate this problem, various methods have been proposed to correct this type of motion a posteriori. These methods correct each volume using a 3D rigid-body matrix having six parameters for translation and rotati...

Automatic body part recognition for CT slices can benefit various medical image applications. Existing methods require large-scale datasets of labeled images. However, the intrinsic structure information in CT volumes was still not fully leveraged. In this paper, we propose unsupervised body part regressor (UBR) to utilize this information. A novel learning framework based on a convolutional ne...

Three-dimensional display utilizing volume rendering is valuable in the display of SPECT data. Volume rendering enhances continuity of structures compared to slice display, and cine display of volume rendered images facilitates understanding of spatial relationships. Image contrast and noise characteristics were analyzed for depth-weighted maximum activity projection, a form of volume rendering...

OBJECTIVE The aim of the present study was to retrospectively evaluate the difference between the preoperative estimated volume and the actual intraoperative graft volume determined in donor right hepatectomies and to evaluate the possible effect of age, gender, and body mass index on the difference. METHODS A total of 225 donor hepatectomies performed at the center between 2016 and 2017 were...

Methods Using overlapping multi-slice 2D single-shot fast spin echo sequences (Philips, 1.5T, TR = 15000 ms, TE = 100 ms, flip angle = 90 degrees, voxel size = 350 × 350 mm, slice thickness = 2.5 mm, SENSE factor = 2, partial Fourier-factor 5/8, slice duration 468 ms) in a fetus at 36 weeks gestation, we applied a novel GPU accelerated super-resolution algorithm for slice-volume registration to...

BACKGROUND Almost nothing is known about the medical aspects of runners doing a transcontinental ultramarathon over several weeks. The results of differentiated measurements of changes in body composition during the Transeurope Footrace 2009 using a mobile whole body magnetic resonance (MR) imager are presented and the proposed influence of visceral and somatic adipose and lean tissue distribut...

Head movement during scanning impedes activation detection in fMRI studies. Head motion in fMRI acquired using slice-based Echo Planar Imaging (EPI) can be estimated and compensated by aligning the images onto a reference volume through image registration. However, registering EPI images volume to volume fails to consider head motion between slices, which may lead to severely biased head motion...

Despite several decades of research into segmentation techniques, automated medical image segmentation is barely usable in a clinical context, and still at vast user time expense. This paper illustrates unsupervised organ segmentation through the use of a novel automated labelling approximation algorithm followed by a hypersurface front propagation method. The approximation stage relies on a pr...

There is a broad push in the cancer imaging community to eventually replace linear tumor measurements with three-dimensional evaluation of tumor volume. To evaluate the potential accuracy of volume measurement in tumors by CT, a gelatin phantom consisting of 55 polymethylmethacrylate (PMMA) spheres spanning diameters from 1.6 mm to 25.4 mm was fabricated and scanned using thin slice (0.625 mm) ...