The 'Salpeter Equation' which has long been known as the 3D version of the 4D Bethe-Salpeter Equation under the Instantaneous Approximation, has a well-defined rationale that stems from the half-century old Markov-Yukawa Transversality Principle (M Y T P) which not only effects an exact 3D reduction from the original (4D) BS form, but also provides an equally exact reconstruction of the 4D BS a...

In this study, we compared the registration effectiveness of 4D cone-beam computed tomography (CBCT) and 3D-CBCT for image-guided radiotherapy in 20 Stage IA non-small-cell lung cancer (NSCLC) patients. Patients underwent 4D-CBCT and 3D-CBCT immediately before radiotherapy, and the X-ray Volume Imaging software system was used for image registration. We performed automatic bone registration and...

Gated 4D cardiac imaging with C-arm CT scanners suffers from insufficient image quality due to strong angular undersampling. To deal with this problem, we suggest an iterative reconstruction method with spatial and temporal total variation regularization based on an established framework which controls the relative contributions of raw data error minimization and regularization. This new method...

The use of image denoising techniques is an important part of many medical imaging applications. One common application is to improve the image quality of low-dose (noisy) computed tomography (CT) data. While 3D image denoising previously has been applied to several volumes independently, there has not been much work done on true 4D image denoising, where the algorithm considers several volumes...

The weak membrane model uses Markov Random Fields within the Bayesian inference framework for image reconstruction and seg-mentation problems. Recently, the model has been extended for the 4D Gabor feature vector space and was applied to texture segmen-tation. A limitation of this technique is that the parameters in the model have to be adjusted for each diierent input image and they are xed th...

This paper presents a modelling approach that can be used by contractors to plan elevated highway reconstruction projects. The proposed model estimates the project duration, productivity rate of the operation, and visualizes the output using 4D modelling. In this paper, the focus is on the demolition and construction of a box girder elevated highways as part of an interchange reconstruction pro...

Motion during data acquisition is a known source of error in medical tomography, resulting in blur artefacts in the regions that move. It is critical to reduce these artefacts in applications such as image-guided radiation therapy as a clearer image translates into a more accurate treatment and the sparing of healthy tissue close to a tumour site. Most research in 4D x-ray tomography involving ...

Fig.4: Velocity time courses in a small region-ofinterest in the descending aorta for different reconstruction types. Fig.5: Exemplary plot of pixel-wise velocities of full k-space data vs. PEAKGRAPPA with a 4D-kernel with Rnet=7.2. R Rnet NACS RMSE [%] r2 GRAPPA 4 2.4 24*48 22.6 0.38 PEAK 3D-kernel 8 7.2 12*8 8.7 0.95 PEAK 4D-kernel 8 7.2 12*8 8.1 0.93 PEAK 4D-kernel 12 9.5 12*8 10.4 0.89 Exte...

AbstractJoint 2D cardiac segmentation and 3D volume reconstruction are fundamental in building statistical anatomy models understanding functional mechanisms from motion patterns. However, due to the low through-plane resolution of cine MR high inter-subject variance, accurately segmenting images reconstructing challenging. In this study, we propose an end-to-end latent-space-based framework, D...

PURPOSE In radiation treatment planning for thoracic and abdominal tumors, 4D-MRI has shown promise in respiratory motion characterization with improved soft-tissue contrast compared to clinical standard, 4D computed tomography (4D-CT). This study aimed to further improve vessel-tissue contrast and overall image quality in 3D radial sampling-based 4D-MRI using a slab-selective (SS) excitation a...