3D Imaging Applications Research Articles

Feature issue of digital holography and 3D imaging (DH): introduction

The OSA Topical Meeting "Digital Holography and 3D Imaging (DH)" was held in Seattle, Washington, 13-17 July 2014. Feature issues based on the DH meeting series have been released by Applied Optics (AO) since 2007. In this year (2014), Optics Express (OE) and AO jointly decided to have one such feature issue in each journal. The feature issue includes 27 papers and covers a large range of topics, reflecting the rapidly expanding techniques and applications of digital holography and 3D imaging. The DH meeting will continue in the future, as expected, and the next meeting is scheduled to be held on 24-28 May 2015, at Shanghai Institute of Optics and Fine Mechanics, Shanghai, China.

AB15. Anatomy of prostate and surrounding tissue in the application of radical prostatectomy.

Surgical technology, especially da Vinci Surgical System, has reinforced people’s understanding of the structure and anatomy of organ under 3D imaging technology in clinical application. The anatomy of prostate and surrounding tissue has features of multiple-layers and great variation. So, application of 3D imaging in anatomy has new progress and positive clinical anticipated effect in radical prostatectomy, especially for complete dissection of tumor, urinary continence and protection of sexual function. Therefore, 3D imaging technology provides an innovative visual experience, and it will create a promising prospect in the preciseness of surgical operation as more experiences accumulated in the future.

3D imaging options and ultrasound contrast agents for the ultrasound assessment of pediatric rheumatic patients.

The application of 3D imaging in pediatric rheumatology helps to make the assessment of inflammatory changes more objective and to estimate accurately their volume and the actual response to treatment in the course of follow-up examinations. Additional interesting opportunities are opened up by the vascularity analysis with the help of power Doppler and color Doppler in 3D imaging. Contrast-enhanced ultrasound examinations enable a more sensitive assessment of the vascularity of inflamed structures of the locomotor system, and a more accurate analysis of treatment's effect on changes in vascularity, and thereby the inflammation process activity, as compared to the classical options of power and color Doppler. The equipment required, time limitations, as well as the high price in the case of contrast-enhanced ultrasound, contribute to the fact that the 3D analysis of inflammatory changes and contrast-enhanced ultrasound examinations are not routinely applied for pediatric patients.

Stochastic tomography and its applications in 3D imaging of mixing fluids

We present a novel approach for highly detailed 3D imaging of turbulent fluid mixing behaviors. The method is based on visible light computed tomography, and is made possible by a new stochastic tomographic reconstruction algorithm based on random walks. We show that this new stochastic algorithm is competitive with specialized tomography solvers such as SART, but can also easily include arbitrary convex regularizers that make it possible to obtain high-quality reconstructions with a very small number of views. Finally, we demonstrate that the same stochastic tomography approach can also be used to directly re-render arbitrary 2D projections without the need to ever store a 3D volume grid.

Stochastic tomography and its applications in 3D imaging of mixing fluids

We present a novel approach for highly detailed 3D imaging of turbulent fluid mixing behaviors. The method is based on visible light computed tomography, and is made possible by a new stochastic tomographic reconstruction algorithm based on random walks. We show that this new stochastic algorithm is competitive with specialized tomography solvers such as SART, but can also easily include arbitrary convex regularizers that make it possible to obtain high-quality reconstructions with a very small number of views. Finally, we demonstrate that the same stochastic tomography approach can also be used to directly re-render arbitrary 2D projections without the need to ever store a 3D volume grid.

Application of neuromuscular blockade and intraoperative 3D imaging in the reduction of basilar invagination

The treatment of basilar invagination in the pediatric age group is dependent on the possibility of preoperative reduction. Reducible lesions obviate a ventral decompression and require a dorsal-only approach for stabilization with or without a suboccipital decompression. The authors describe a technique of intraoperative reduction of basilar invagination with the use of general anesthesia and neuromuscular blockade in the presence of crown halo traction. Using the O-arm device, a 3D CT scan is generated in the sagittal plane to demonstrate the reduction intraoperatively. This technique was successful in 6 pediatric patients with basilar invagination. The average age of the patients was 10.8 years, and they were followed for a mean period of 8.5 months. The patients had mild basilar invagination or partial reduction in extension on preoperative MR imaging. Intraoperative reduction was demonstrated in all patients by using the reported technique with intraoperative CT. All patients underwent occipitocervical fusion, and all but one underwent a suboccipital decompression. There were no complications related to the operation, and all but one reported improvement of symptoms on the last postoperative visit. Intraoperative reduction performed using neuromuscular blockade and intraoperative traction is an effective method for further reduction of basilar invagination in the pediatric age group. This is the first reported application of intraoperative CT imaging performed using the O-arm device in craniocervical surgery in which successful reduction is demonstrated in detail.

Direct tomography with chemical-bond contrast

Three-dimensional (3D) X-ray imaging methods have advanced tremendously during recent years. Traditional tomography uses absorption as the contrast mechanism, but for many purposes its sensitivity is limited. The introduction of diffraction, small-angle scattering, refraction, and phase contrasts has increased the sensitivity, especially in materials composed of light elements (for example, carbon and oxygen). X-ray spectroscopy, in principle, offers information on element composition and chemical environment. However, its application in 3D imaging over macroscopic length scales has not been possible for light elements. Here we introduce a new hard-X-ray spectroscopic tomography with a unique sensitivity to light elements. In this method, dark-field section images are obtained directly without any reconstruction algorithms. We apply the method to acquire the 3D structure and map the chemical bonding in selected samples relevant to materials science. The novel aspects make this technique a powerful new imaging tool, with an inherent access to the molecular-level chemical environment.

Clinical Application of 3D Imaging for Assessment of Treatment Outcomes

This paper outlines the clinical application of CBCT for assessment of treatment outcomes, and discusses current work to superimpose digital dental models and 3D photographs. Superimposition of CBCTs on stable structures of reference now allow assessment of 3D dental, skeletal and soft tissue changes for both growing and non-growing patients. Additionally, we describe clinical findings from CBCT superimpositions in assessment of surgery and skeletal anchorage treatment.

Digital content creation: A global view on curriculum design

Digital content creation: A global view on curriculum design

Application of cone beam CT 3D images to cephalometric analysis

Orthodontic diagnosis is currently based primarily on two-dimensional (2D) measurements. The development of maxillofacial cone beam X-ray computed tomography (CBCT) has promoted the use of three-dimensional (3D) measurements for orthodontic diagnosis. This technology is also expected to generate new analytic methods aiming at establishing optimal occlusion according to the individual's maxillary shape and function. However, during the transitional stage from 2D to 3D measurements, it is necessary to relate 3D data to existing data analysis methods (e.g., lateral cephalogram) for the assessment of skeletal and dental relationship. Our objectives were to develop a new cephalometric analysis method based on 3D data obtained by CBCT from four aspects: (1) measurement of magnification of cephalogram, (2) assessment of the dimensional accuracy of CBCT images, (3) development of a method of cephalometric analysis using CBCT images and (4) comparison of cephalometric analytical values obtained from CBCT images with those obtained from existing cephalograms. The results demonstrated that our analytical method facilitated cephalometric analysis of CBCT images and therefore allowed direct comparison of CBCT images with existing cephalograms. Cephalometric analysis using CBCT images resulted in a smaller range of inter-operator measurement variability than that using conventional cephalograms.

Tele-Dietetics with Food Images as Dietary Intake Record in Nutrition Assessment

Tele-dietetic is not common in current practice. To promote this, food images as dietary intake records should be validated before application. Two-dimensional (2D) digital images are reliable and have been validated in previous studies. However, the depth is virtual with a 2D image. And ingredient types, sauce types, cooking methods, and amount of oil added have not been researched for accurate food analysis. This study was designed to compare the reliability and accuracy of these parameters estimated using 2D and three-dimensional (3D) food images. Ten nutritionists evaluated 10 selected food items between January 2008 and June 2008. Ten 2D food images and ten 3D images of the same food items were captured for the observers' evaluation. The actual weightings or volume of the food items were measured as the gold standard for comparisons. Intraclass correlations (ICCs), percentage agreement, and one-sample t-tests were analyzed to compare the reliability and accuracy of each type of images. Both images showed high reliability among observers with 3D images giving less variance (2D: ICC=0.916, F=17.001, p<0.001; 3D: ICC=0.846, F=6.501, p<0.001). Both images resulted in good ingredient and cooking method identification, but 3D was better in identifying sauce type. 2D images provided better volume and oil estimation when compared with 3D images. The research findings confirmed the application of 2D and 3D food images as reliable and accurate dietary records for nutritionists to evaluate clients' dietary habits. This implied the feasibility of tele-dietetics that one's nutrition status could be assessed over the Internet.

A New Dynamic in Mass Spectral Imaging of Single Biological Cells

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) has unique capabilities in the area of high-resolution mass spectrometric imaging of biological samples. The technique offers parallel detection of native and non-native molecules at physiological concentrations with potentially submicrometer spatial resolution. Recent advances in SIMS technology have been focused on generating new ion sources that can in turn be used to eject more intact molecular and biological characteristic species from a sample. The introduction of polyatomic ion beams, particularly C60, for TOF-SIMS analysis has created a whole new application of molecular depth profiling and 3D molecular imaging. However, such analyses, particularly at high lateral resolution, are severely hampered by the accompanying mass spectrometry associated with current TOF-SIMS instruments. Hence, we have developed an instrument that overcomes many of the drawbacks of current TOF-SIMS spectrometers by removing the need to pulse the primary ion beam. The instrument samples the secondary ions using a buncher that feeds into a specially designed time-of-flight analyzer. We have validated this new instrumental concept by analyzing a number of biological samples generating 2D and 3D images showing molecular localization on a subcellular scale, over a practical time frame, while maintaining high mass resolution. We also demonstrate large area mapping and the MS/MS capability of the instrument.

Automatic seed initialization for the expectation-maximization algorithm and its application in 3D medical imaging

Statistical partitioning of images into meaningful areas is the goal of all region-based segmentation algorithms. The clustering or creation of these meaningful partitions can be achieved in number of ways but in most cases it is achieved through the minimization or maximization of some function of the image intensity properties. Commonly these optimization schemes are locally convergent, therefore initialization of the parameters of the function plays a very important role in the final solution. In this paper we perform an automatically initialized expectation-maximization algorithm to partition the data in medical MRI images. We present analysis and illustrate results against manual initialization and apply the algorithm to some common medical image processing tasks.

Virtual 3-dimensional modeling as a valuable adjunct to aesthetic and reconstructive breast surgery

Three-dimensional (3D) imaging technology currently is used by various commercial industries as a method for analyzing objects and shapes. Recent work from our group and others offer data to support the use of 3D imaging as a valuable tool in aesthetic and reconstructive breast surgery. We have developed a system for creating 3D breast models that provides clinical data that can help guide surgical management. With 3D breast models, surgeons are able to visually assess the size, shape, contour, and symmetry of the breast, as well as obtain quantitative breast measurements and volumetric calculations. Three-dimensional imaging may be applied to various plastic surgery procedures including breast reconstruction with implant/tissue expanders, local flap reconstruction, free-flap reconstruction, breast augmentation, and breast reduction surgery. The novel application of 3D imaging in these settings represents a significant advance from traditional approaches to aesthetic and reconstructive breast surgery in which surgical procedures are based on 2-dimensional photographs and visual size estimates.

Electro-Optic Adaptive Lens as a New Eyewear

Adaptive lens with the capability of changing the focusing power has important applications in 3D imaging, optical information processing, and ophthalmology. We demonstrate a switchable electroactive lens with very high diffraction efficiencies using a circular array of electrode pattern filled with liquid crystal as the active medium to be used as an adaptive eyewear. Electrically adjustable lens allows the focal length to be voltage controlled without bulky and inefficient mechanical movement. Binary Fresnel zone plates using liquid crystal as active material have been demonstrated for imaging applications, but the diffraction efficiency is low. The lens is flat and the thickness of the liquid crystal is 5 μm. Diffraction efficiencies exceeding 90% has been achieved for an 8-level diffractive lens. The lens can be operated as both positive and negative lens. Design, modeling, fabrication, and characterization of the lens is presented. Using nematic liquid crystal, the lens is polarization dependent and two crossed lenses are integrated to form a complete lens. The ON- and OFF-state of the electrically controlled lens allow near- and distance-vision respectively for presbyopia eyes.

Image analysis and superimposition of 3-dimensional cone-beam computed tomography models

Three-dimensional (3D) imaging techniques can provide valuable information to clinicians and researchers. But as we move from traditional 2-dimensional (2D) cephalometric analysis to new 3D techniques, it is often necessary to compare 2D with 3D data. Cone-beam computed tomography (CBCT) provides simulation tools that can help bridge the gap between image types. CBCT acquisitions can be made to simulate panoramic, lateral, and posteroanterior cephalometric radioagraphs so that they can be compared with preexisting cephalometric databases. Applications of 3D imaging in orthodontics include initial diagnosis and superimpositions for assessing growth, treatment changes, and stability. Three-dimensional CBCT images show dental root inclination and torque, impacted and supernumerary tooth positions, thickness and morphology of bone at sites of mini-implants for anchorage, and osteotomy sites in surgical planning. Findings such as resorption, hyperplasic growth, displacement, shape anomalies of mandibular condyles, and morphological differences between the right and left sides emphasize the diagnostic value of computed tomography acquisitions. Furthermore, relationships of soft tissues and the airway can be assessed in 3 dimensions.

Application of 3D Imaging in Objective Assessment of Scar Pliability

Application of 3D Imaging in Objective Assessment of Scar Pliability

Atlas-guided non-uniform attenuation correction in cerebral 3D PET imaging

Photon attenuation in tissues is the primary physical degrading factor limiting both visual qualitative interpretation and quantitative analysis capabilities of reconstructed Positron Emission Tomography (PET) images. This study investigates the implementation and applicability of transmission atlas-guided attenuation correction in cerebral 3D PET imaging, thus eliminating the need for acquisition of a measured transmission scan. Patient-specific attenuation map is derived by anatomic standardization through nonlinear warping of a stereotactic transmission template obtained by averaging 11 scans of normal subjects. This template is coregistered to a specially designed tracer-specific 18F-[FDG] template constructed by scanning 17 normal subjects in resting condition during tracer uptake in a dark room. This emission template is first coregistered and spatially normalized to preliminary PET images of subjects corrected for scatter and attenuation using an approximate calculated method. The resulting transformation matrices are recorded and re-applied to the transmission template. The derived attenuation map is then forward projected to generate attenuation correction factors to be used for correcting the subjects' PET data. Twelve cerebral clinical studies are used for evaluation of the developed attenuation correction technique as compared to the standard pre-injection measured transmission-based method used in clinical routine. Statistical Parametric Mapping (SPM2) analysis is used to assess significant differences between images obtained using both techniques. The subjective qualitative assessment shows no significant visual differences between atlas-guided and transmission-based attenuation correction methods. However, the quantitative voxel-based analysis comparing atlas-guided to transmission-based attenuation corrections suggest that regional brain metabolic activity increases significantly bilaterally in the superior frontal and precentral gyri, in addition to the left middle temporal gyrus and the left frontal lobe. Conversely, activity decreases in the corpus callosum in the left parasagittal region. A new non-uniform attenuation correction method is thus proposed, which is suitable for both research and clinical routine applications in 3D brain PET imaging on a transmissionless PET scanner or when a patient-specific transmission scan is not available.

Applications of 3D imaging in orthodontics: part I.

Part I of this paper describes the background, general concepts, available techniques and the clinical applications of recording external craniofacial morphology in three dimensions. Part II explores the different 3D techniques of imaging the dental arches, and their possible uses in orthodontic diagnosis and treatment.

Techniques, clinical applications and limitations of 3D reconstruction in CT of the abdomen.

Enhanced z-axis coverage with thin overlapping slices in breath-hold acquisitions with multidetector CT (MDCT) has considerably enhanced the quality of multiplanar 3D reconstruction. This pictorial essay describes the improvements in 3D reconstruction and technical aspects of 3D reconstruction and rendering techniques available for abdominal imaging. Clinical applications of 3D imaging in abdomen including liver, pancreaticobiliary system, urinary and gastrointestinal tracts and imaging before and after transplantation are discussed. In addition, this article briefly discusses the disadvantages of thin-slice acquisitions including increasing numbers of transverse images, which must be reviewed by the radiologist.