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This installment of our quarterly Clinical Management series examines how the hospital operating room is becoming a safer place for patients. Thanks to such technological breakthroughs as 3-D images, virtual patients and robots, surgeons can operate with more accuracy and efficiency.
OBJECTIVE: To study the three-dimensional (3D) reconstruction and 3D visualization of the pancreas and create anatomy of the digitalized visual pancreas so as to construct a concrete basis for virtual operation and surgical operation on pancreas. METHODS: The digital imaging data of pancreas, duodenum, common bile duct, arteries and veins were obtained from the Virtual Chinese Human-Female 1 (VCH-F1) and processed using ACDSee and Photoshop so as to reconstruct 3D pancreas digitally and realize 3D visualization of pancreas. RESULTS: We successfully 3D reconstructed and visualized the pancreas and the peri-pancreatic structures: the duodenum, the common bile duct, the inferior vena cava, the portal vein vessels, the aorta, the ceoliac trunk vessels. The 3D and visualized pancreas manifested itself with its complete structure as well as its adjacency to other tissues. CONCLUSIONS: The 3D reconstruction and 3D visualization of the pancreas based on the digital data of VCH-F1 produces a digitally visualized pancreas, which promises us a novel method for virtual operation on pancreas, clinical operation on pancreas and anatomy of 3D visualized pancreas.
A mathematical model of the human upper limb was developed based on high-resolution medical images of the muscles and bones obtained from the Visible Human Male (VHM) project. Three-dimensional surfaces of the muscles and bones were reconstructed from Computed Tomography (CT) images and Color Cryosection images obtained from the VHM cadaver. Thirteen degrees of freedom were used to describe the orientations of seven bones in the model: clavicle, scapula, humerus, radius, ulna, carpal bones, and hand. All of the major articulations from the shoulder girdle down to the wrist were included in the model. The model was actuated by 42 muscle bundles, which represented the actions of 26 muscle groups in the upper limb. The paths of the muscles were modeled using a new approach called the Obstacle-set Method [33]. The calculated paths of the muscles were verified by comparing the muscle moment arms computed in the model with the results of anatomical studies reported in the literature. In-vivo measurements of maximum isometric muscle torques developed at the shoulder, elbow, and wrist were also used to estimate the architectural properties of each musculotendon actuator in the model. The entire musculoskeletal model can be reconstructed using the data given in this paper, along with information presented in a companion paper which defines the kinematic structure of the model [26].
The understanding of cardiac anatomy is crucial for the interventional arrhythmologist. In spite of the introduction of several nonfluroscopic navigational tools, some of them capable of reconstructing a computer-based surrogate of the endocardial surface of the heart cavities, simple fluoroscopy with or without the aid of angiographic techniques is still the most widely used method to guide mapping and ablation procedures. In some instances, fluoroscopic and angiographic methods have no possible replacement to unravel certain arrhythmologically useful anatomic landmarks. New interpretations of cardiac architecture show the need to challenge some traditional anatomic views, like the concept of septums within the heart. The fluoroscopic anatomy also needs to be reconsidered in the light of the new attitudinally oriented nomenclature. This article presents an overview of the fluoroscopic anatomy of the heart. When pertinent, some anatomical concepts are discussed in more detail like the triangle of Koch, the pyramidal space, and the interatrial groove. In the sections on the atria and on the ventricles, the authors focus on the anatomic information that is relevant for mapping and ablation from a fluoroscopic viewpoint, providing some hints on how best to depict the morphological features from the stance of the interventional arrhythmologist. The Visible Human Slice and Surface Server using data sets from the Visible Human Male and Female Project, has been used to facilitate the understanding of the fluoroscopic anatomy.
This study develops and demonstrates a realistic x-ray imaging simulator with computerized observers to maximize lesion detectability and minimize patient exposure. A software package, ViPRIS, incorporating two computational patient phantoms, has been developed for simulating x-ray radiographic images. A tomographic phantom, VIP-Man, constructed from Visible Human anatomical colour images is used to simulate the scattered portion using the ESGnrc Monte Carlo code. The primary portion of an x-ray image is simulated using the projection ray-tracing method through the Visible Human CT data set. To produce a realistic image, the software simulates quantum noise, blurring effects, lesions, detector absorption efficiency and other imaging artefacts. The primary and scattered portions of an x-ray chest image are combined to form a final image for computerized observer studies and image quality analysis. Absorbed doses in organs and tissues of the segmented VIP-Man phantom were also obtained from the Monte Carlo simulations. Approximately 25,000 simulated images and 2,500,000 data files were analysed using computerized observers. Hotelling and Laguerre-Gauss Hotelling observers are used to perform various lesion detection tasks. Several model observer tasks were used including SKE/BKE, MAFC and SKEV. The energy levels and fluence at the minimum dose required to detect a small lesion were determined with respect to lesion size, location and system parameters.
A software package, incorporating two computational patient phantoms, has been developed for optimizing X-ray radiographic imaging. A tomographic phantom, visible photographic Man tomographic phantom (VIP-Man), constructed from Visible Human anatomical color images is used to simulate the scattered portion of an X-ray system using the Electron Gamma Shower National Research Council (EGSnrc) Monte Carlo code. The primary portion of an X-ray image is simulated using the projection ray-tracing method through the Visible Human CT data set. To produce a realistic image, the software simulates quantum noise, blurring effects, lesions, detector absorption efficiency, and other imaging artifacts. The primary and scattered portions of an X-ray chest image are combined to form a final image for future observer studies and image quality analysis. Absorbed doses in organs and tissues of the segmented VIP-Man phantom were also obtained from the Monte Carlo simulations. This paper presents methods of the simulator and preliminary results.
A geometrical analysis tool for investigating muscle length change in cerebral palsy (CP) patients is presented. A subset of anatomically based geometries from the International Union of Physiological Sciences (IUPS) Physiome Project is used, which is derived from the visible human (VH) data set with muscle attachment information, and customised using volume-preserving free-form deformation (FFD), the 'host-mesh' technique. The model's intended use is to provide pre- and post-surgery assessment for muscle lengthening, a surgery performed to help slacken tight muscles and improve gait. The model is illustrated using healthy patient data from motion capture as a validation followed by three CP case studies to highlight its use. The methodology is presented in three stages, (1) a FFD of the complete lower limb, (2) a focused geometric study on the semimembranosus (SM) and gastrocnemius (GT) muscles, and (3) an improved hybrid mechanics-FFD approach as an improvement for future analysis, with differentiation between muscle and tendon lengthening, and contact detection between sliding muscles. Finally, the issues, limitations, in particular with the marker system, and model improvements are discussed.
On the 26 June 2000 the teams involved in mapping the human genome announced to the world's media that they had completed the 'first draft'. This paper is a content analysis of UK press coverage of the announcement, particularly of the ethical, legal and social implications (ELSIs) contained therein. Widespread and highly visible coverage of the completion of the Human Genome Project (HGP) was characterised by press ambivalence towards, on the one hand, the optimistic future of post-genomic medicine and, on the other hand, the pessimistic vision of post-genomic society. Coverage of the positive medical implications characteristically echoed the exuberance felt by the champions of human genetic research, focusing on longevity and a cure for cancer. Articles on ELSIs either repeated long-standing concerns about genetic discrimination and the redesign of human life, or introduced more novel topics such as the commercialisation of genetic science, genetic determinism and 'living forever'. Press reports on the more novel ELSIs addressed the political and economic context of the science, its 'social value' and its complexity, issues that have often been lacking in media coverage of human genetics. However, as a contribution to public awareness and policy frameworks surrounding human genetic science, press coverage was deficient in important respects. The HGP's proponents were the press's key source of information about its ELSIs. Journalists addressed only a limited number of ELSIs, focusing on issues that were 'manageable' by regulation or legislation rather than concerns such as risk, clinical utility or opportunity costs. Furthermore, those articles that addressed the more novel concerns were often presented using sensationalist news values. As a media representation of science, coverage of the 'first draft' in the UK press demonstrated both 'source dependence' and a bias toward the legitimacy of science, although the coverage of the more novel ELSIs indicated some mistrust toward scientific governance.
The purpose of this study was to investigate the relationship between human field motion and preferred visible wavelengths. The study was based on the principle of resonancy from Rogers' science of unitary human beings; 201 subjects were tested using a modified version of Ference's human field motion test (HFMT). Two matrices of color were projected to provide an environment for the measurement of preferred visible wavelengths. There was no statistically significant relationship (r = 0.0387, p = 0.293) between scores on the human field motion test and preferred visible wavelengths as measured in nanometers. The Rogerian concept of accelerated human field rhythms being coordinate with higher frequency environment patterns was not supported in this study. Questions concerning the validity of the HFMT were expressed and were based upon the ambiguity of the terminology of the instrument and the lack of understanding of the concepts used to describe human field motion. Recommendations include the use of other methods to study Rogers' framework, and the development of other instrumentation to measure human field motion.
In principle the Visible Human data sets are an ideal basis for building electronic atlases. While it is easy to construct such atlases by just offering the possibility of browsing through the 2D slices, constructing realistic 3D models is a huge project. As one rather easy way to establish 3D use, we have registered the Visible Human data to the already existing 3D atlas VOXEL-MAN/brain. This procedure enables one to lookup anatomical detail in an atlas based on radiological images. Concerning the segmentation problem, which is the prerequisite for a real 3D atlas, we have developed an interactive classification method that delivers realistic perspective views of the Visible Human. As these volume based methods require high-end workstations, we finally have developed a multimedia program that runs on standard PCs and uses Quicktime VR movies.
A simple optical backpointer has been designed as a retrofit for isocentric radiotherapy machines. Two lasers are used to project two fan beams of light which intersect in line with the central ray of the radiation beam. The system is mechanically rugged, and the projected cross is visible even in room light.
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More than 1200 attendees came together at the 3(rd) HUPO World Congess in Beijing, October 25-27, 2004. In numerous different sessions the wide range of proteomic areas became visible. The HUPO Brain Proteome Project (HUPO BPP) organized an evening session on October 23, presenting the first results of two pilot studies as well as the newest, very positive international development in this field. The rising importance became even more apparent in the plenary presentation of all HUPO initiatives and the following congress activities.
Patterns of cellular adhesion were created on a surface using novel photochemistry that is stimulated with visible light. A glass surface coated with polyethylene glycol is nonadhesive to a variety of adherent mammalian cell types. Treatment of that surface with a mixture of tris(bipyridyl)ruthenium(II) chloride, ammonium persulfate, and a tryptophan derivative or tryptophan-bearing peptide in conjunction with irradiation with visible light (447 nm) made the surface adhesive to several cell types including mouse fibroblasts, human myoblasts, and human lung tumor cells. Immunostaining data suggest that tryptophan-containing peptides are crosslinked intact to the surface by this chemistry, which enables patterning of peptides containing only naturally occurring amino acids. Microscopic patterns of cellular adhesion were created with this chemistry by projecting microscopic patterns of visible light with a digital micromirror array. Using this method, regions of cellular adhesion were patterned with single-cell resolution.
Anatomically based finite element geometries are becoming increasingly popular in physiological modelling, owing to the demand for modelling that links organ function to spatially distributed properties at the protein, cell and tissue level. We present a collection of anatomically based finite element geometries of the musculo-skeletal system and other organs suitable for use in continuum analysis. These meshes are derived from the widely used Visible Human (VH) dataset and constitute a contribution to the world wide International Union of Physiological Sciences (IUPS) Physiome Project (www.physiome.org.nz). The method of mesh generation and fitting of tricubic Hermite volume meshes to a given dataset is illustrated using a least-squares algorithm that is modified with smoothing (Sobolev) constraints via the penalty method to account for sparse and scattered data. A technique ("host mesh" fitting) based on "free-form" deformation (FFD) is used to customise the fitted (generic) geometry. Lung lobes, the rectus femoris muscle and the lower limb bones are used as examples to illustrate these methods. Geometries of the lower limb, knee joint, forearm and neck are also presented. Finally, the issues and limitations of the methods are discussed.
We developed a modification of Tessier's zygoma plasty to increase anterior and lateral projection of the malar eminences in 8 patients with malar hypoplasia. The four steps of our modification are: (1) access solely through an intraoral upper sulcus incision; (2) osteotomy of the inferior orbital rim at a more medial site and of the lateral orbital rim more cephalad; (3) careful preservation of both the zygomaticomaxillary buttress and the zygomatic arch; and (4) use of a cranial bone graft alone, as a wedge, to stabilize the rotated zygoma, without the need for plate or screw fixation. Eight patients have undergone this procedure. Follow-up ranged from 4 to 15 months. There have been no complications. All 8 patients have achieved excellent accentuation of their malar eminences, with maintenance of symmetry. The increase in malar eminence projection has improved overall facial form in these patients. The modified Tessier zygoma plasty offers a stable and predictable technique for improving facial form. It provides a very natural correction for deficient malar projection, without introducing visible scars.
The luminance of the background and of the target (visual acuity letter) was measured for five commonly used visual acuity screen materials. Most materials were found to be highly nonlambertian. A greater than threefold difference in reflectance normal to the surface was found for the respective screens tested. The percent polarization maintained by each screen material, using American Optical Vectograph systems, was measured. The relative illuminations generated by eight projector systems were compared. A discussion of the factors and recommendations for improvements related to projected chart visibility are made.
This study describes a three-dimensional (3D) filtering algorithm for magnetic resonance angiography (MRA) image enhancement. Based on the properties of 3D MRA data, the algorithm uses the dispersion range of the 13 outputs of a 3D directional low-pass filter bank to identify the vessel structure and control the processing of MRA data. Vascular structures in the data are preserved while the components of static tissues and isolated noise impulses are reduced by the processing. As a result, the small vessels have been enhanced and visibility of vessels in the projected image has been improved.