Computational models of oral and craniofacial development, growth, and repair.

This paper illustrates how biological and clinical problems stimulate research in biomedical informatics and how such research contributes to their solution. The computational models described use techniques from Logic Programming, Machine Learning, Computer Vision, and Biomathematics. They address problems in the development, growth, and repair of oral and craniofacial tissues arising in cell biology, clinical genetics, and dentistry. At the micro-level, the dynamic interaction of cells in the oral epithelium is modeled. At the macro-level, models are constructed of either the craniofacial shape of an individual or the craniofacial shape differences within and between healthy and congenitally abnormal populations. In between, in terms of scale, there are models of normal dentition and the use of computerized expert knowledge to guide the design of dental prostheses used to restore function in partially edentulous patients.

Decision support tools for clinical trial design.

Many published clinical trials are poorly designed, suggesting that the protocol was incomplete, disorganised, or contained errors. This fact motivated the development of a suite of decision support tools for the design of randomised controlled clinical trials. In this paper we describe these tools, discussing both underlying theoretical issues and usage of the tools. The core tool--Design-a-Trial (DaT)--critiques data entered so as to guide design of a scientifically and ethically sound trial. DaT outputs a text protocol describing the trial, and a corresponding symbolic representation. Linked to DaT is a tool for authoring plans that form part of the trial. A key feature of this tool is the provision of macros for describing commonly occurring plan constructs. We describe another linked tool which generates solutions to Prolog queries requesting advice on how a plan should be revised so as to comply with safety and efficacy requirements. The user is able to navigate a path through the solution search space by interacting with natural language representations of the Prolog sub-goals. This provides the flexibility to generate useful and informative partial solutions, symbolic and textual, for inclusion in the symbolic plan representation and protocol document, respectively.

Combining biometric and symbolic models for customized, automated prosthesis design.

In a previous paper [Artif. Intell. Med. 5 (1993) 431] we described RaPiD, a knowledge-based system for designing dental prostheses. The present paper discusses how RaPiD has been extended using techniques from computer vision and logic grammars. The first employs point distribution and active shape models (ASMs) to determine dentition from images of casts of patient's jaws. This enables a design to be customized to, and visualised against, an image of a patient's dentition. The second is based on the notion of a path grammar, a form of logic grammar, to generate a path linking an ordered sequence of subcomponents. The shape of an important and complex prosthesis component can be automatically seeded in this fashion. Combining these models now substantially automates the design process, beginning with a photograph of a dental cast and ending with an annotated and validated design diagram ready to guide manufacture.

Safety and computer-aided design of chemotherapy plans.

Previously, generic principles were derived empirically from examples of reasoning about the efficacy and safety of chemotherapy. Some of the principles were used in a prototype decision-support system for managing patients through chemotherapy. It reminded clinicians which, how, and when drugs were to be given; suggested treatment modifications as a result of detected adverse events; and warned how unplanned actions undermine efficacy or exacerbate hazardous side effects. Here, we investigate the reuse of these safety principles to generate symbolic and textual representations of new chemotherapy plans. In clinical trials of chemotherapy, a written protocol is essential, especially in obtaining ethical approval. The symbolic representation, from which textual extracts are derived, can be used in conjunction with software for managing chemotherapy.