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A growing group of institutions and individuals use Internet connections to reach information sources. Large health care organizations now see electronic records as essential to providing cost-effective health care. The Visible Human Project represents the entire three-dimensional anatomy of a cadaver.
Interactive documents for use with the World Wide Web have been developed for viewing multi-dimensional radiographic and visual images of human anatomy, derived from the Visible Human Project. Emphasis has been placed on user-controlled features and selections. The purpose was to develop an interface which was independent of host operating system and browser software which would allow viewing of information by multiple users. The interfaces were implemented using HyperText Markup Language (HTML) forms, C programming language and Perl scripting language. Images were pre-processed using ANALYZE and stored on a Web server in CompuServe GIF format. Viewing options were included in the document design, such as interactive thresholding and two-dimensional slice direction. The interface is an example of what may be achieved using the World Wide Web. Key applications envisaged for such software include education, research and accessing of information through internal databases and simultaneous sharing of images by remote computers by health personnel for diagnostic purposes.
A 3D anatomically based patient-specific finite element (FE) model of patello-femoral (PF) articulation is presented to analyse the main features of patella biomechanics, namely, patella tracking (kinematics), quadriceps extensor forces, surface contact and internal patella stresses. The generic geometries are a subset from the model database of the International Union of Physiological Sciences (IUPS) (http://www.physiome.org.nz) Physiome Project with soft tissue derived from the widely used visible human dataset, and the bones digitised from an anatomically accurate physical model with muscle attachment information. The models are customised to patient magnetic resonance images using a variant of free-form deformation, called 'host-mesh' fitting. The continuum was solved using the governing equation of finite elasticity, with the multibody problem coupled through contact mechanics. Additional constraints such as tissue incompressibility are also imposed. Passive material properties are taken from the literature and implemented for deformable tissue with a non-linear micro-structurally based constitutive law. Bone and cartilage are implemented using a 'St-Venant Kirchoff' model suitable for rigid body rotations. The surface fibre directions have been estimated from anatomy images of cadaver muscle dissections and active muscle contraction was based on a steady-state calcium-tension relation. The 3D continuum model of muscle, tendon and bone is compared with experimental results from the literature, and surgical simulations performed to illustrate its clinical assessment capabilities (a Maquet procedure for reducing patella stresses and a vastus lateralis release for a bipartite patella). Finally, the model limitations, issues and future improvements are discussed.
We present here an anatomically based model of the human masticatory system that provides a framework for simulating the complex chewing process. The initial motivation for creating this model was the desire to have a computational model of the human jaw that can be used to simulate the action of simple bites, and to calculate the stresses and forces on the teeth that are involved. The model created also provides a platform that can be used to investigate other features of the masticatory system. To construct this global model, individual models of the bones of the skull and jaw were created from generic data sets. Geometric models of the muscles of mastication were also created and attached to the appropriate bones. To complete this initial model, representations of the crowns of the teeth were created and a basic model of the temporomandibular joint (TMJ) was included. The finite element method was used to solve for the stresses and strains created by the loading conditions during a clenching simulation involving the mandible bone. The model presented here is also discussed in relation to a model of the entire musculo-skeletal system being developed as part of the Physiome Project.
The medical imaging technologies have been used for detecting tumors through the years. Tumors that can be viewed in imaging are usually big enough to contain billion tumor cells. Some patients may be cured if detected earlier and the surgery is performed well. Those lead to molecular imaging and image-guided surgery research activities, which post new challenges on large scale imaging data management and 3-D visualization. The goal of this project is to develop 3-D imaging informatics system that can interactively navigate large scale of organ and molecular levels imaging data for early diagnosis and treatment planning.
The purpose of this study was to explore a feasible method for the reconstruction of the nasal and temporal bone structures of the Chinese virtual human project and provide a more accurate and facilitated way view them three-dimensionally (3D). The 3-D Slicer software was used to reconstruct the anatomic structures of the human nose and temporal bone. Segmentation and extraction of the contours of the ROI (region of interest) in each single slice were conducted and the processed volume data was transferred into the 3-D Slicer. After resegmentation, a set of labeled maps of the ROI were produced. Based on these maps, the 3D surface models of the tissues of interest were constructed. Four groups of paranasal sinuses, nasal septa, middle and inferior turbinates, temporal bones, tympanic cavities, mastoid air cells, sigmoid sinuses, and internal carotid arteries were reconstructed successfully. These models show spatial relationships and orientation between them. The results show that the 3-D Slicer may be used for the 3D visualization of parts of anatomic structures in the nose and temporal bone based on the first Chinese virtual human data, and thus, can facilitate the observation and understanding of the anatomic structures in this area.
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The three-dimensional (3D) modeling from anatomical images is revealed to be a remarkable learning tool in anatomy. This is particularly true for the pelvis area and the urogenital tract. The authors present here a 3D reconstruction of the male urogenital tract from the Visible Korean Human data. The segmentation of 440 anatomical images was arranged in a pile and processed by the SURFdriver software to build an interactive 3D model. Forty-two anatomical structures were reconstructed, including kidneys, ureters, urinary bladder (outer and inner boundaries), urethra, testes, epididymides, ducti deferens, seminal vesicles, prostate, rectum, anal canal, abdominal aorta, superior mesenteric artery, renal arteries, inferior vena cava, renal veins, lumbar vertebrae, intervertebral discs, sacrum, hip bones, femurs, and skin. Three-dimensional models of 42 anatomical structures can be individually and interactively manipulated. In addition, the use is able to control the transparency of the model. The aim of this computerized modeling is to present a learning tool for students and patients. In the near future, it could be the basis of new simulation tools for surgeon's training.
The central role that human dissection has long held in clinical education is being reevaluated in many institutions. Despite the impression that many institutions are abandoning dissection, very few have and most of those have reinstated dissection within a few years. What are the inherent qualities that lead institutions back to dissection? In our efforts to redesign a shortened dissection course, our consultations with a broad range of clinicians lead us to understand how the rhythms of clinical practice are modeled and developed in the small-group setting of the dissection laboratory. Following further consultation with colleagues who have experimented with different models of anatomy instruction, we discuss three themes in support of dissection. First, problem-solving in the dissection laboratory develops the habits-of-mind of clinical practice. Second, relating dissection to imaging modalities develops the spatial reasoning skills needed to understand computer simulations, interpret imaging data, and interact with surgeons, radiologists, and patients. Third, the human face of dissection fosters self-reflection and integration of the cognitive and affective skills required for medical practice. Through group process, the collaborative effort of dissection teams develops essential of attributes of clinical professionalism.
During the last decade, use of radio frequency (RF) applications like mobile phones and other wireless devices, has increased remarkably. This has triggered numerous studies related to possible health risks due to the exposure of RF electromagnetic (EM) fields. One safety aspect is the coupling of EM fields with active and passive implants in the human body. While interactions with active implants have been quite extensively researched, only a few studies have focused on passive implants. The present article reviews interaction mechanisms and studies of passive metallic, that is, conductive, implants in common external RF EM fields. It is found that implants have been mostly studied numerically, and experimental studies are rare. Furthermore, the studies cover mostly far-field conditions and only a few have studied implants in near fields. A summary of results indicates that a conductive object in tissues may cause notable local enhancement of the EM field and thus enhanced power absorption. The degree of enhancement depends, for example, on the orientation, the dimensions, the shape, and the location of the implant. However, in most of the cases, the field enhancement has not been strong enough to cause remarkable excess heating (more than 1 degrees C) of tissues.
The Visible Human digital datasets make it possible to develop computer-based anatomical training systems that use virtual anatomical models (virtual body structures-VBS). Medical schools are combining these virtual training systems and classical anatomy teaching methods that use labeled images and cadaver dissection. In this paper we present a customizable web-based three-dimensional anatomy training system, W3D-VBS. W3D-VBS uses National Library of Medicine's (NLM) Visible Human Male datasets to interactively locate, explore, select, extract, highlight, label, and visualize, realistic 2D (using axial, coronal, and sagittal views) and 3D virtual structures. A real-time self-guided virtual tour of the entire body is designed to provide detailed anatomical information about structures, substructures, and proximal structures. The system thus facilitates learning of visuospatial relationships at a level of detail that may not be possible by any other means. The use of volumetric structures allows for repeated real-time virtual dissections, from any angle, at the convenience of the user. Volumetric (3D) virtual dissections are performed by adding, removing, highlighting, and labeling individual structures (and/or entire anatomical systems). The resultant virtual explorations (consisting of anatomical 2D/3D illustrations and animations), with user selected highlighting colors and label positions, can be saved and used for generating lesson plans and evaluation systems. Tracking users' progress using the evaluation system helps customize the curriculum, making W3D-VBS a powerful learning tool. Our plan is to incorporate other Visible Human segmented datasets, especially datasets with higher resolutions, that make it possible to include finer anatomical structures such as nerves and small vessels.
Functional Neuroanatomy, an interactive electronic neuroanatomical atlas, was designed for first year medical students. Medical students have much to learn in a limited time; therefore a major goal in the atlas design was that it facilitate rapid, accurate information retrieval. To assess this feature, we designed a testing scenario in which students who had never taken a neuroanatomy course were asked to complete two equivalent tests, one using the electronic atlas and one using a comparable hard copy atlas, in a limited period of time. The tests were too long to be completed in the time allotted, so test scores were measures of how quickly correct information could be retrieved from each source. Statistical analysis of the data showed that the tests were of equal difficulty and that accurate information retrieval was significantly faster using the electronic atlas when compared with the hard copy atlas (P < 0.0001). Post-test focus groups (n = 4) allowed us to infer that the following design features contributed to rapid information access: the number of structures in the database was limited to those that are relevant to a practicing physician; all of the program modules were presented in both text and image form on the index screen, which doubled as a site map; pages were layered electronically such that information was hidden until requested, structures available on each page were listed alphabetically and could be accessed by clicking on their name; and an illustrated glossary was provided and equipped with a search engine.
Classical anatomic atlases cannot provide the spectrum of views and the detail required in modern diagnostic and surgical techniques. Computer modeling opens the possibility to choose any view from one single model. A computerized model of the hand is presented, which has been obtained by segmentation and graphic modeling of the Visible Human dataset. In addition to being able to choose arbitrary viewpoints, it allows interrogation of the chosen views by mouse click. We believe the functions of these new kinds of atlases are superior to the classical ones.
Radiological images are commonly used as important tools in medical diagnoses and treatment. Different modalities of medical images provide uniquely different content. Hence, it is natural and desirable to combine different image modalities to obtain additional new information to enhance clinical assessment. However, given the current technology, radiological images are not always sufficiently informative to permit diagnosis and treatment. In order to address this problem, we fused selected portions of the Chinese Visible Human (CVH) dataset with MRI images from a patient. Specifically, we segmented the caudate nucleus, the lentiform nucleus, and the thalamus in the CVH dataset and then registered and fused this dataset with corresponding MRI images using both rigid and nonrigid registration techniques. After rigid and nonrigid registration, the CVH and MRI images largely coincided with each other. The shape, relationship, and position of focal areas and neural structures were clearly displayed. Using volume and surface rendering, these images were three-dimensionally reconstructed to display the neural structures of interest within the brain. These structures can be rotated at will and observed from different angles. Our research indicates that the fusion of CVH and patients' MRI images can enhance the amount of neural information available to physicians and lay a foundation for the clinical use of the CVH dataset.
Virtual reality based learning of human anatomy is feasible when a database of 3D organ models is available for the learner to explore, visualize, and dissect in virtual space interactively. In this article, we present our latest work on photorealistic virtual anatomy applications based on the Chinese Visible Human (CVH) data. We have focused on the development of state-of-the-art virtual environments that feature interactive photo-realistic visualization and dissection of virtual anatomical models constructed from ultra-high resolution CVH datasets. We also outline our latest progress in applying these highly accurate virtual and functional organ models to generate realistic look and feel to advanced surgical simulators.
Virtual anatomy presents significant advantages over the reality of a cadaver as it can provide different views and perspectives, portability, longevity, standardization, diversity and most importantly the opportunity to learn the anatomy of the living human body instead of the corpse. Virtual anatomy is the life-like appearance of visible anatomy, a good example of which is the evolution of the Visible Human. Racial and statistical diversity is already developing as the population of photographic "Visible Humans" is now at least 10. Virtual anatomy should include additional diversity and therefore, consideration should be given to the preparation of more visible anatomy that will better support the virtual integration of all areas of physiology, kinematics, pathology and pathophysiology, development and evolution. Integration of anatomists with mathematicians, computer scientists, information scientists, physiologists, pathologists and clinicians (and LIST other basic scientist) is needed in order to facilitate this development. As this unfolds it is proposed, or challenged, that anatomists should maintain their position of responsibility for building anatomy as the foundation for all medical and healthcare education. In order to maintain that position they must understand and participate in this development and enjoy the rewards of teaching more visually empowering, functional, and clinical anatomy. The trip is a long one and is only about to begin but the train is leaving. Are you on board?
The practice of medicine and conduct of research in major segments of the biologic sciences have always relied on visualizations to study the relationship of anatomic structure to biologic function. Traditionally, these visualizations have either been direct, via vivisection and postmortem examination, or have required extensive mental reconstruction. The revolutionary capabilities of 3-D and 4-D medical imaging modalities, together with computer reconstruction and rendering of multidimensional medical and histological volume image data, obviate the need for physical dissection or abstract assembly. The availability of the Visible Human Datasets from the National Library of Medicine, coupled with the development of advanced computer algorithms to accurately and rapidly process, segment, register, measure, and display high resolution 3-D images, has provided a rich opportunity to help advance these important new imaging, visualization, and analysis methodologies from scientific theory to clinical practice.