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ABSTRACT: This paper examines an approach for integrating 3D structural reasoning, using computer models of the human anatomy, with diagnostic reasoning based on Bayesian networks in order to probabilistically predict injuries to anatomic structures from gunshot wounds. An interactive 3D graphical system has been created which allows the user to visualize different bullet path hypotheses and computes the probability that an anatomical structure associated with a given penetration path is injured. The probabilities derived are essential for mediating between structural reasoning and diagnostic reasoning. 1: Introduction The focus of this research is on integrating 3D structural reasoning (using computer models of the human anatomy), with diagnostic reasoning based on Bayesian networks, in order to probabilistically predict injury to anatomic structures from gunshot wounds. 1 Penetrating trauma is responsible for a large proportion of civilian deaths in the United States and is also a major...
07/1998;
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Norman I. Badler,
Bonnie L. Webber, John R. Clarke,
M. D. Diane,
M. Chi,
Michael J. Hollick,
Nick Foster,
Evangelos Kokkevis,
Omolola Ogunyemi,
Dimitri N. Metaxas,
Jonathan Kaye,
Rama Bindiganavale
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ABSTRACT: The MediSim system extends virtual environments (both local and network) to represent simulated medical personnel interacting with simulated casualties. Our technology fosters dual-use applications involving planning, training, and evaluation of both medical corpsmen and civilian EMTs. Behaviors and behavioral control are being developed for the medical corpsmen that will enable their actions on the digital battlefield to conform to both military practice and medical protocols. From situationally-appropriate injury models, a set of physical and behavioral manifestations in a simulated casualty will be determined and portrayed on a three-dimensional body. Keywords: Injury models, medical procedures, computer simulation, virtual environments, physicsbased modeling, medical decision support. 1 Introduction The MediSim system extends virtual environments to represent simulated medical personnel interacting with simulated casualties. Fig. 1 diagrams the major components of the MediSim sys...
11/1997;
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Foundations of Intelligent Systems, 10th International Symposium, ISMIS '97, Charlotte, North Carolina, USA, October 15-18, 1997, Proceedings; 01/1997
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ABSTRACT: this paper presents a method for choosing the optimal combination of treatment actions, taking into account interactions among the available therapeutic and diagnostic procedures. The
10/1996;
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ABSTRACT: This paper addresses "kinds and focuses of relevance" that a language-generating clinical decision-support system should adhere to during activities in which a health care provider's attention is on his or her patient and not on a computer screen. During such "patient-centered" activities, utterances generated by a computer system intrude on patient management. They must be thus seen by HCPs as having immediate clinical relevance, or, like the continual ringing of ICU monitors, they will be ignored. This paper describes how plan recognition and plan evaluation can be used to achieve clinical relevance. The work is being done in the context of the TraumAID project, whose overall goal is to improve the delivery of quality trauma care during the initial definitive phase of patient management. Given an early pilot study that showed that physicians using TraumAID disliked the continuous presentation of its entire management plan, we decided to explore how TraumAID could restrict commentary to only those situations in which a comment could make a clinically significant difference to patient management. We took advantage of the fact that actions that involve resources that need to be brought to the trauma bay or that can only be done elsewhere must be ordered. Since orders can be rescinded, comments pointing out problems with an order can potentially make a clinically significant difference to patient management. The contributions of this paper are (1) pointing out additional constraints on language generation raised by the desire to convey information to listeners attending to something other than an computer terminal, and (2) pointing out some features of plan inference and evaluation raised by multiple goal planning in a complex domain.
04/1996;
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04/1996;
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ABSTRACT: We present a model for simulating casualties in virtual environments for real-time medical training. It allows a user to choose diagnostic and therapeutic actions to carry out on a simulated casualty who will manifest appropriate physiological, behavioral, and physical responses. Currently, the user or a "stealth instructor" can specify one or more injuries that the casualty has sustained. The model responds by continuously determining the state of the casualty, responding appropriately to medical assessment and treatment procedures. So far, we have modeled four medical conditions and over twenty procedures. The model has been designed to handle the addition of other injuries and medical procedures.
Presence Teleoperators & Virtual Environments 02/1996; · 0.69 Impact Factor
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ABSTRACT: Recent research has abstracted diagnosis away from the activity needed to acquire information and to act on diagnosed disorders. In some problem domains, however, such abstraction is counter-productive and does not reflect real-life practice, which integrates diagnostic and therapeutic activity. Trauma management is a case in point. Here, we discuss a formalization of the integrated approach taken in TraumAID, a system we have developed to serve as an artificial aide to residents and physicians dealing with multiple trauma. Among other things, the active pursuit of information raises the question of what is and what is not worth pursuing. In TraumAID 2.0, we take the view that the process of diagnosis should continue only as long as it is likely to make a difference to future actions. That view is formalized in the goal-directed diagnostic paradigm (GDD). Unlike other diagnostic paradigms, goal-directed diagnosis is first and foremost concerned with setting goals based on its conclusi...
03/1995;
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ABSTRACT: . In producing realistic, animatable models of the human body, we see much to be gained from developing a functional anatomy that links the anatomical and physiological behavior of the body through fundamental causal principles. This paper describes our current Finite Element Method implementation of a simplified lung and chest cavity during normal quiet breathing and then disturbed by a simple pneumothorax. The lung model interacts with the model of the chest cavity through applied forces. The models are modular, and a second lung and more complex chest wall model can be added without disturbing the model of the other lung. During inhalation, a breathing force (corresponding to exertion of the diaphragm and chest wall muscles) is applied, causing the chest cavity to expand. When this force is removed (at the start of exhalation), the stretched lung recoils, applying pressure forces to the chest wall which cause the chest cavity to contract. To simulate a simple pneumothorax, the intra...
12/1994;
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ABSTRACT: We present an integrated approach between anatomical and physiological modeling that is useful in medical training and visualization of internal body organ function. In particular, we model the breathing mechanism in the respiratory system because it involves physiological change, such as gas exchange, that depends on gross anatomical deformations (volume changes). We describe our initial model of the lungs for a simplified process of normal, quiet breathing. Our system consists of two integrated levels of abstraction: (i) geometric and physics-based modeling (shape extraction, motion, deformations, and graphical rendering); (ii) mathematical relationships among parameters that express physical laws and physiological processes. We present experiments that demonstrate graphically the organ geometry, physics, and physiological dynamics. 1 Introduction With advances in computer graphics and faster hardware, computers are becoming an increasingly important tool for visualizing medical da...
11/1994;
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[show abstract]
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ABSTRACT: Much planning research assumes that the goals for which one plans are known in advance. That is not true of trauma management, which involves both a search for relevant goals and reasoning about how to achieve them. TraumAID is a consultation system for the diagnosis and treatment of multiple trauma. It has been under development jointly at the University of Pennsylvania and the Medical College of Pennsylvania for the past eight years. TraumAID integrates diagnostic reasoning, planning and action. Its reasoner identifies diagnostic and therapeutic goals appropriate to the physician 's knowledge of the patient's state, while its planner advises on beneficial actions to next perform. The physician 's lack of complete knowledge of the situation and the time limitations of emergency medicine constrain the ability of any planner to identify what would be the best thing to do. Nevertheless, TraumAID's Progressive Horizon Planner has been designed to create a plan for patient care that is in...
05/1994;
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01/1994
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ABSTRACT: The TraumAID system has been designed to provide on-line decision support throughout the initial definitive management of injured patients. Here we describe its retrospective evaluation and the use we subsequently made of judges comments on the validation data to evaluate TraumaTIQ, a new critiquing interface for TraumAID, investigating the question of whether, with timely recording of information, a system could produce commentary in line with that of human experts. Our results show that (1) comparable commentary can be produced, and (2) validation studies, which take great time and effort to conduct, can produce useful data beyond their original design goals.
Artificial Intelligence in Medicine.
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Norman I. Badler, John R. Clarke,
Michael J. Hollick,
Evangelos Kokkevis,
Dimitris Metaxas,
Ramamani Bindiganavale,
Bonnie L. Webber,
Diane M. Chi,
Nick Foster,
Omolola Ogunyemi,
Jonathan Kaye
[show abstract]
[hide abstract]
ABSTRACT: The MediSim system extends virtual environments (both local and network) to represent simulated medical personnel interacting with simulated casualties. Our technology fosters dual-use applications involving planning, training, and evaluation of both medical corpsmen and civilian EMTs. Behaviors and behavioral control are being developed for the medical corpsmen that will enable their actions on the digital battlefield to conform to both military practice and medical protocols. From situationally-appropriate injury models, a set of physical and behavioral manifestations in a simulated casualty will be determined and portrayed on a three-dimensional body.
Center for Human Modeling and Simulation.
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[show abstract]
[hide abstract]
ABSTRACT: In producing realistic, animatable models of the human body, we see much to be gained from developing a functional anatomy that links the anatomical and physiological behavior of the body through fundamental causal principles. This paper describes our current Finite Element Method implementation of a simplified lung and chest cavity during normal quiet breathing and then disturbed by a simple pneumothorax. The lung model interacts with the model of the chest cavity through applied forces. The models are modular, and a second lung and more complex chest wall model can be added without disturbing the model of the other lung. During inhalation, a breathing force (corresponding to exertion of the diaphragm and chest wall muscles) is applied, causing the chest cavity to expand. When this force is removed (at the start of exhalation), the stretched lung recoils, applying pressure forces to the chest wall which cause the chest cavity to contract. To simulate a simple pneumothorax, the intrapleural pressure is set to atmospheric pressure, which removes pressure forces holding the lung close to the chest cavity and results in the lung returning to its unstretched shape.
Center for Human Modeling and Simulation.
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ABSTRACT: This paper outlines the particular demands that multiple trauma makes on systems designed to provide appropriate decision support, and the ways that these demands are currently being met in our system, TraumAID. The demands follow from: (1) the nature of trauma and the procedures used in its diagnosis, (2) the need to adjust diagnostic and therapeutic procedures to available resource levels, (3) the role of anatomy in trauma and the need for anatomical reasoning, (4) the role of non-specialists in managing trauma, and (5) the competing demands of multiple injuries and the consequent need for planning. We believe that these demands are not unique to multiple trauma, so that the paper may be of general interest to expert system research and development.
Technical Reports (CIS).
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ABSTRACT: In an earlier paper [Rymon et a1 89], we showed how domain localities and regularities can be used to reduce the complexity of finding a trauma management plan that satisfies a set of diagnostic and therapeutic goals. Here, we present another planning idea - Progressive Horizon - useful for optimizing such plans in domains where planning can be regarded as an incremental process, continuously interleaved with situation - goals analysis and plan execution. In such domains, planned action cannot be delayed until all essential information is available: A plan must include actions intended to gather information as well as ones intended to change the state of the world. Interleaving planning with reasoning and execution, a progressive horizon planner constructs a plan that answers all currently known needs but has only its first few actions optimized (those within its planning horizon). As the executor cames out actions and reports back to the system, the current goals and the plan are updated based on actual performance and newly discovered goals and information. The new plan is then optimized within a newly set horizon. In this paper, we describe those features of a domain that are salient for the use of a progressive horizon planning paradigm. Since we believe that the paradigm may be useful in other domains, we abstract from the exact techniques used by our program to discuss the merits of the general approach.
Technical Reports (CIS).
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[show abstract]
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ABSTRACT: Much planning research assumes that the goals for which one plans are known in advance. That is not true of trauma management, which involves both a search for relevant goals and reasoning about how to achieve them. TraumAID is a consultation system for the diagnosis and treatment of multiple trauma. It has been under development jointly at the University of Pennsylvania and the Medical College of Pennsylvania for the past eight years. TraumAID integrates diagnostic reasoning, planning and action. Its reasoner identifies diagnostic and therapeutic goals appropriate to the physician’s knowledge of the patient’s state, while its planner advises on beneficial actions to next perform. The physician’s lack of complete knowledge of the situation and the time limitations of emergency medicine constrain the ability of any planner to identify what would be the best thing to do. Nevertheless, TraumAID’s Progressive Horizon Planner has been designed to create a plan for patient care that is in keeping with the standards of managing trauma.
IRCS Technical Reports Series.
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[show abstract]
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ABSTRACT: We describe a system, TraumAID, which has been designed to provide decision support throughout the initial definitive management of severely injured patients (i.e., after their initial evaluation, resuscitation, and stabilization). Over the course of initial definitive management, TraumAID recommends appropriate procedures to be carried out, based on currently available evidence and on the complexity and urgency of the situation. TraumAID's ability to deal flexibly with complex and often urgent situations comes from its ability to reason separately about the management goals that should be achieved and about the means that are situationally appropriate for achieving them. In this paper, we describe TraumAID's approach to trauma management in more detail, showing in particular how it enables TraumAID to adapt its reasoning and recommendations to the urgency with which a patient's condition must be addressed.
Technical Reports (CIS).
