background: hdr brachytherapy is one of the commonest methods of nasopharyngeal cancer treatment. in this method, depending on how advanced one tumor is, 2 to 6 gy dose as intracavitary brachytherapy is prescribed. due to high dose rate and tumor location, accuracy evaluation of treatment planning system (tps) is particularly important. common methods used in tps dosimetry are based on computat...

OBJECTIVES This study sought to assess the diagnostic accuracy of cone beam computed tomography (CBCT) with different voxel sizes and intraoral digital radiography with photostimulable phosphor (PSP) plate for detection of periapical (PA) bone lesions. MATERIALS AND METHODS In this ex vivo diagnostic study, one-millimeter defects were created in the alveolar sockets of 15 bone blocks, each wi...

Computed tomography (CT) images of the lungs provide high resolution views of the airways. Quantitative measurements such as lumen diameter and wall thickness help diagnose and localize airway diseases, assist in surgical planning, and determine progress of treatment. Automated quantitative analysis of such images is needed due to the number of airways per patient. We present an approach involv...

Background Dynamic contrast enhanced cardiovascular magnetic resonance imaging (DCE-CMR) allows for high-resolution analysis of myocardial perfusion by preserving important spatial information. However high resolution perfusion quantification suffers from the poor signal-to-noise ratio (SNR) of voxel-based data. Previously spatial averaging (segmental or sub-segmental analysis) has been used to...

A method for quantitative assessment of tree structures is reported allowing evaluation of airway or vascular tree morphology and its associated function. Our skeletonization and branch-point identification method provides a basis for tree quantification or tree matching, tree-branch diameter measurement in any orientation, and labeling individual branch segments. All main components of our met...

This paper proposes an unsupervised tumour segmentation approach for PET data. The method computes the volumes of interest (VOIs) with sub-voxel precision by considering the limited image resolution and partial volume effects. First, an improved anisotropic diffusion filter is used to remove image noise. A hierarchical local and global intensity active surface modelling scheme is then applied t...

Micro- and mesostructures of multiphase materials obtained from tomography image acquisition are an ever more important database for simulation analyses. Huge data sets reconstructed 3d volumes typically as voxel grids call criteria measures to find affordable balance accuracy efficiency. The present work shows a mesostructure concrete in the elastic deformation range, how computational complex...

Stack misalignment in cardiac MR cine series distorts the correct appearance of anatomical features and reduces the reproducibility of volumetric measurements computed for diagnostic purposes. This paper describes a method for correction of stack misalignment in cardiac MR series. Our method involves registration against a reference volume and features a prominent enhancement designed to circum...

A method for computationally efficient skeletonization of three-dimensional tubular structures is reported. The method is specifically targeting skeletonization of vascular and airway tree structures in medical images but it is general and applicable to many other skeletonization tasks. The developed approach builds on the following novel concepts and properties: fast curve-thinning algorithm t...

Dynamic contrast-enhanced 4-D MR renography has the potential for broad clinical applications, but suffers from respiratory motion that limits analysis and interpretation. Since each examination yields at least over 10-20 serial 3-D images of the abdomen, manual registration is prohibitively labor-intensive. Besides in-plane motion and translation, out-of-plane motion and rotation are observed ...