Discussion

The advances in medical imaging capabilities since 1970 have been developed, applied, and accepted at a volume and pace unprecedented in medical history. Computer and digital radiographic technology and techniques have significantly expanded the possibilities for accurate, quantitative, and noninvasive visualization and measurement of intracorporeal morphology and function. These advances have provided a variety of new diagnostic methodologies for clinical evaluation of health and disease. 3D imaging and visualization methods are emerging as the method of choice in many clinical examinations, replacing some previously routine procedures, and significantly complementing others. The continuing evolution of 3D and visualization imaging promises even

FIGURE 30 Synthesis of cell models into gross anatomic framework using the Visible Human Male torso model. Upper left panel shows gross anatomy of spine and dorsal root at centimeter scale. Upper right panel shows magnified view of synthesized conductance pathway through dorsal root toward mesenteric ganglia. Lower panels show two groups of neurons within ganglia at micron scale. The individual neurons are modeled and rendered from confocal microscope data, just as macrostructures (e.g., the brain) are produced from CT or MRI scans. Virtual endoscopic fly-throughs along the conduction pathways can be produced, beginning at the gross anatomy level for spatial context, proceeding to finer and finer resolutions through magnification of field of view, ending in virtual exploration within single cells. See also Plate 125.

FIGURE 30 Synthesis of cell models into gross anatomic framework using the Visible Human Male torso model. Upper left panel shows gross anatomy of spine and dorsal root at centimeter scale. Upper right panel shows magnified view of synthesized conductance pathway through dorsal root toward mesenteric ganglia. Lower panels show two groups of neurons within ganglia at micron scale. The individual neurons are modeled and rendered from confocal microscope data, just as macrostructures (e.g., the brain) are produced from CT or MRI scans. Virtual endoscopic fly-throughs along the conduction pathways can be produced, beginning at the gross anatomy level for spatial context, proceeding to finer and finer resolutions through magnification of field of view, ending in virtual exploration within single cells. See also Plate 125.

greater capabilities for accurate noninvasive clinical diagnoses and treatment, as well as for quantitative biological investigations and scientific exploration, targeted at ever increasing our understanding of the human condition and how to improve it.

The effective extraction of all information contained in 3D and 4D images requires new conceptual approaches and methodologies in image processing. Multidimensional image visualization and analysis is largely an exploratory process, directed at understanding better the nature of the object imaged. There are essentially three major tasks associated with any analysis of biomedical imagery: (1) display, (2) editing, and (3) measurement. These tasks are interrelated, often overlapping, and coexist in a rather classical channel of feedback, feed-forward information passing. The capabilities of a multidimensional image visualization and analysis system should be fine-tuned to effectively facilitate these tasks and to provide adroit exploration of all relationships (i.e., structural and functional) existing within the data. The rate of evolution and acceptance of 3D biomedical imaging systems will be increasingly dependent on effective, compliant, and extensible software packages and user interfaces [3,25,58]. In the near term these will be carefully customized and implemented with user-specific needs and style in mind, but there are exciting prospects for a universal interface for multiple applications that will greatly facilitate the uniform delivery of health care and sharing of health-care resources, resulting in significant savings in health-care costs.

It is perhaps of value to consider where the recent impressive and continuing advances in biomedical imaging and visualization capabilities are leading, and how they fit into the overall future picture of diagnostic medicine and associated biological disciplines. Without question, the cutting edge in these disciplines and most other aspects of the biomedical sciences is increasingly in the molecular biochemical and biophysical spheres, and quite certainly the most important advances during the foreseeable future will be in the realms of molecular and genetic engineering and mapping. The increases in biomedical investigative power being provided by current imaging modalities to obtain dynamic quantitative images of structural-functional relationships within organs and organ systems by minimally invasive methods will provide the basis for the last frontier of continued important advances in these disciplines, at least in the macroscopic realm [3,25]. It is a reasonable prediction that further development and exploitation of these techniques will be of continuing importance, but increasingly significant future advances will most probably be at the molecular and submolecular rather than at macroscopic anatomic and functional levels.

Perhaps the most exciting development in this regard will be the ability to image (measure) accurately the spatial distribution and magnitude of any selected chemical element and/or metabolic function in any region of the body. This challenging, but not impossible, extension of the state of the art in medical imaging might be called "tomochemistry" or "biochemical imaging." Even though the state of the art in the current technology of energy sources and selective detectors does not permit practical application, they do exist in experimental laboratories. For example, rapid progress is being made in the field of laser imaging. Furthermore, miniature detectors with adequate energy discriminating and signal-to-noise characteristics are being developed. Thus, fabrication of a clinically useful 3D reconstruction machine with both anatomic structural and chemical composition sensing capabilities is possible in the near future. The "ideal" 3D imaging and visualization system would provide simultaneously and rapidly all of the advantages and eliminate all of the limitations of the different current imaging modalities, as well as those yet to be conceived.

The extent to which such a system may ultimately evolve is speculation, but it is evident that 21st-century medicine will represent a culmination of continuing evolutionary progress in multidimensional imaging and visualization methods. The medical and scientific communities can expect to benefit in improved health care from a continuum of marvelous synergistic advances in imaging and visualization technology.

0 0

Post a comment