Imaging Roundtable
MEDICAL IMAGING—TRANSFORMING HEALTH CARE
Drawing on specialists from industry, academia and health care professions, a panel discussion met to discuss the new advances in imaging and showcase how patients benefit from sustained investments in research on medical imaging through the continued development of less invasive, more precise and cost-effective diagnostics and treatments. The briefing was sponsored by the National Electrical Manufacturers Association in collaboration with the Academy of Radiology Research and Research!America.
In the past, dramatic advances in medical imaging technologies have allowed physicians to detect, diagnose and treat diseases earlier and more accurately, often reducing costs. Medical imaging is extending human vision into the very nature of disease, enabling a new and more powerful generation of diagnosis and intervention. Military Medical Technology has been able to draw together a number of the speakers and give them the chance to present their views to you in hopes of broadening the knowledge base and facilitate medical imaging transformation.
Jim Davis
Vice President of Diagnostic Imaging
Sales and Marketing
GE Healthcare
Chairman of the Board of Directors
National Electrical Manufacturers Association
Imaging’s contributions and transformations span the entire health care spectrum, including: medical research; medical practice— that is, for individual patients; and health system efficiencies.
Medical imaging has dramatically changed how physicians measure, manage, diagnose, treat, prevent and even think about medical illnesses and conditions. This has fostered seismic changes in the landscape of U.S. health care—in how, where and in what way health care is delivered.
These transformations include:
- Enabling physicians to see inside the body with such clarity that they no longer have to infer or guess how diseased an organ is or how blocked an artery might be. Perhaps one of the greatest transformations in modern medicine is the ability of physicians to provide less-invasive therapies.
- Medical imaging enables a range of lessinvasive, highly targeted medical therapies that translate into better and more comfortable care for patients. Because they are less invasive, these treatments mean fewer complications, shorter hospital stays, and in many cases, no incisions or surgery.
As much progress as we have made, we now stand on the cusp of some truly revolutionary innovations. Innovations that will shatter our current notions of disease and health care delivery. Our collective efforts will enable the earlier detection of disease.
For example:
- The ability to diagnose disease earlier and at the molecular level;
- The ability to personalize medicine and target treatments; and
- The ability to incorporate images into electronic health records and transmit that data anywhere in the world in seconds.
These capabilities will alter how physicians diagnose, treat, manage, predict and ultimately prevent disease.
Imaging advances form the epicenter of key scientific breakthroughs, by enabling clinicians and researchers to visualize critical physiologic variables such as oxygen consumption, blood flow, glucose metabolism, and tissue hypoxia as they occur in living tissues and cells.
In the case of cancer, molecular imaging can potentially identify altered genes, molecular pathways, and tumor-specific receptors. This information can shed light on tumor behavior—information that is critical in understanding how different tumors in different people will respond to different drugs and therapies. This allows for the personalization of drug therapies and the targeting of the right therapy to the right patient.
These advances are occurring across a range of imaging modalities, such as CT, MR, and ultrasound, nuclear medicine and PET.
Equally promising is the progress we are seeing in developments in image enhancement agents and imaging probes—all of which are used to improve our ability to see biochemical changes that lead to the initial onset of disease and will ultimately help patients to live longer, healthier lives.
Imaging not only contributes to improved health care for individual patients, but also makes huge contributions to the health care system as well.
Medical imaging makes the health care system work more efficiently, translating into improved workflow and, ultimately, cost savings. Such savings are often apparent, as when imaging replaces surgery or in the efficiency maximization brought about by picture archiving and communication systems (PACS). Physicians can share patient records and images without paper or film. Going paperless helps physicians care for patients, while helping hospitals save money.
Imaging also promotes savings through better patient outcomes. When patients are treated effectively the first time—earlier in the process—hospitals can reduce length of stay and readmissions. This is good for the patient and the provider.
Imaging’s new frontier, fusing digital imaging with information technology, is introducing savings that stretch throughout the health delivery system.
Many existing studies highlight the benefits, cost savings and productivity enhancements that imaging contributes to our health care system.
James H. Thrall, M.D.
Radiologist-in-Chief
Massachusetts General Hospital and the
Juan M. Taveras Professor of Radiology at Harvard Medical School
The Blueprint for Imaging in Biomedical Research (BIBR) is an initiative focused on developing a guide to:
- Understanding the scope and magnitude of opportunities presented by contemporary and emerging imaging methods, and
- Exploiting those opportunities fully for the benefit of patients and the acceleration of scientific discovery in conjunction with the NIH Roadmap for Medical Research.
The guide is intended to be used by a diverse group of stakeholders, including researchers across the spectrum of biomedical science as well as radiologists and imaging scientists.
The centerpiece of the BIBR process was a conference in the fall of 2005 sponsored by the Academy of Radiology Research, the American College of Radiology, the American Roentgen Ray Society, and the Radiological Society of North America with additional financial support from the National Institute of Biomedical Imaging and Bioengineering and the National Cancer Institute. More than 50 scientific societies and other public and private sector organizations, both within the imaging disciplines and in other fields, were invited to nominate participants. Presentations and brainstorming sessions were used to prepare an outline that now serves as the framework for writing the blueprint and collecting additional supporting materials from attendees and other scientists.
Four overarching themes emerged from the conference:
Imaging research is interdisciplinary. Knowledge from many fields, including physics, engineering, genetics and genomics, molecular and cell biology, and statistics is required to develop new imaging methods. The array of imaging methods may be compared to a toolkit, with interdisciplinary teams needed to maintain communication between tool builders and tool users. The strongest research is based on close collaboration between these groups.
The power of imaging methods is increasing significantly. Improvements in the spatial, temporal and contrast resolution of imaging methods, coupled with the development of new methods for functional and molecular imaging, enable investigators to study living systems, including humans, from the level of molecules to the level of the entire organism over time without sacrificing the integrity of those subjects. This increasing power will accelerate scientific discovery and the development of new therapies. It will benefit patients, who will receive better, more personalized diagnosis and therapy, and all of society, through new knowledge, a healthier population, and a more efficient health system. One major result has been the virtual elimination of exploratory surgery.
Imaging methods are increasingly used for therapy as well as diagnosis. Image-guided therapy offers increasing opportunities to target disease selectively without harming normal tissue. The result is improved efficacy with reduced side effects. These benefits are being achieved in areas such as localized drug delivery, targeted gene therapy and imageguided surgery and intravascular interventions.
The digital revolution is expanding the capabilities of imaging. Digital methods for acquiring, storing, transmitting and processing image data provide the ability to extract quantitative information from images, to develop computer-aided detection systems, and to view image data in creative new ways such as three-dimensional displays and the fusion of anatomic and functional data in the same image. As a result, more information can be extracted, and more value-generated, per-unit cost with reduced risk to patients.
The blueprint will explore these themes in greater detail and make specific recommendations to the NIH and other federal agencies for new research initiatives and programs. The BIBR planning committee recognizes that the blueprint will continually evolve as the scientific stakeholders develop new knowledge. The process of discovery in imaging science, as in other fields, is a cyclic endeavor in which each advance suggests new directions of inquiry and, ultimately, further innovation. The blueprint process is truly a race without a finish line.
Dr. Roderic Pettigrew
Director
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
The mission of the National Institute of Biomedical Imaging and Bioengineering (NIBIB) is to improve health by leading the development and accelerating the application of biomedical technologies. The institute is committed to integrating the physical and engineering sciences with the life sciences to advance basic research and medical care. To accomplish this mission, the institute has undertaken a number of programs. Examples include: lead on an NIH Roadmap initiative on molecular imaging probes; an initiative on Quantum Projects aimed at solving major heath care problems; and training programs geared to training multidisciplinary scientists.
Technological innovation is of paramount importance. Over the last 25 years, of the top 15 medical advances ranked in a physician’s survey, half are related to imaging technologies. Most significantly, topping the list are magnetic resonance imaging and computer tomography. These technologies have revolutionized the diagnosis and prevention of disease.
A multidisciplinary team of researchers has developed a new imaging system that may shorten surgery times and greatly improve the success rates of surgery to remove seizurecausing brain regions in patients with debilitating and untreatable epilepsy. The system integrates detailed information about brain anatomy, biochemistry, and electrical changes that occur during seizures, and allows surgeons in the operating room to more precisely pinpoint, and then remove the damaged brain tissue. Several patients who suffered for years with debilitating seizures are now seizure free following this pioneering surgery.
Deep brain stimulation is a therapy used to control the tremors of patients suffering from Parkinson’s Disease. This therapy involves inserting a hairthin wire inside the area of the brain that controls movement, and attaching the wire to an impulse generator. The challenge for surgeons is identifying the target area of the brain. New computerized brain-mapping technology may help to pinpoint precise locations in the brain for wire insertion. As these technologies continue to improve, this procedure will be able to be done with greater accuracy and less operating time.
Advances in magnetic resonance imaging have made a profound difference in the detection of breast and prostate cancers. MRI can detect cancers not seen by mammography. Over the past 20 years, breast cancer tumor size at diagnosis has decreased by more than half and lumpectomies have replaced radical mastectomies as the standard of care in many instances. Though lagging behind breast cancer detection, new imaging technologies are under development for detecting prostate cancer as well, such as 3T dynamic contrast enhanced MRI.
Image-guided minimally invasive surgery is changing the practice of medicine. With the development and use of new computers and bioinformatics, biomaterials, micro-tools and robotics, older, more invasive surgical procedures for diagnosis and treatment of disease are being replaced. For example, non-invasive angiography now allows doctors to view the coronary arteries in three dimensions. Shape memory polymers are being adapted for use with image-guided micro-tools in the treatment of plaque in the arteries of potential stroke patients.
Imaging technologies are also rapidly evolving in the field of cellular and molecular imaging. Cellular and molecular imaging will reveal biological changes in the human body that were previously undetectable. Optical-based cellular imaging is already being used to detect the cells of some cancers at the earliest stages of disease.
Advanced imaging technologies are now being used to help doctors detect, diagnose, monitor and treat numerous diseases more accurately and earlier in the disease process. NIBIB’s goal is to provide support for the science necessary for these fields to mature and to accelerate the translation of important breakthroughs from basic research to clinical studies and ultimately to patients.
Sanford M. Simon
Professor and Head of the Laboratory of Cellular Biophysics
Rockefeller University
Optical imaging has been undergoing a revolution in its capabilities and sensitivity, a revolution which is responsible for numerous advances at the molecular and cellular level. These innovations have allowed the bridging of scales of study, from visualizing the steps of single molecular motors on the scale of a few nanometers, to the mapping of activity in the cerebral cortex on a millimeter-by-millimeter basis.
There are many reasons why there has been such a rapid advance of in imaging. These include advances in electronics, advances in fluorophore chemistry, new imaging modalities and advances in genetic engineering.
There are three reasons why imaging is having such an impact on biomedical sciences:
- Imaging allows us to study living systems
- Imaging gives information about the variations, the diversity of a system
- Imaging allows us to examine a multitude of sizes simultaneously from single molecules to whole organisms
What follows are some examples of two of these.
Imaging allows us to study living systems. There are many things that can be learned from a living organism that cannot be learned from a cadaver. Blood flow is one obvious example. Imaging has made it possible to follow the intraocular vasculature during development and disease. This in-vivo vascular imaging approach is valuable for monitoring normal development, progression of disease, efficacy of experimental treatments in animal models of retinal disease, and development of blood vessels in the retina. It is also a useful test system for compounds that facilitate or block the growth of blood vessels, and the use of stem cells from the bone marrow to repopulate the retina.
Imaging allows us to examine a multitude of sizes simultaneously: from single molecules to whole organisms.
The linkage between a proton gradient and generation/hydrolysis of ATP is essential for metabolism. One of the models for how this proton- ATPase works involves a rotary movement. Not only could the rotary movement of a single molecule be observed, it was possible to measure the rates of movement, the steps of movement, and even the forces generated by the movement.
Imaging allows us to study dynamic processes in cells, such as how they secrete. Secretion is essential for cells to grow, for release of hormones and for brain function—this is how the transmitters are released from nerve cells. Further, many diseases in the body (diabetes) and the brain (Parkinson’s, Schizophrenia) involve a disruption in the process of secretion. Secretion involves membrane-bound packets that release material to the outside and then internalize material from the surface.
We know many of the molecules involved from biochemistry, genetics and toxicology, but we do not know how they function. Imaging allows us to follow the dynamics of the release of hormones or enzymes or follow the processes by which they are taken back up into cells.
The ability to use photons to probe activity minimizes the degree to which the experimental observations perturb the biological preparation. The ability to genetically encode reporters into neurons allows the scientist to use multiphoton excitation to selectively excite specific areas of the cortex of the brain. This allows the activity of the receptors in a single spine on a single dendrite of a neuron to be imaged in the mouse brain and even large-scale mapping of activity in cortical networks.
The ability to image on multiple scales of size, from the single molecule to the whole organism, is further enhanced by our ability to image in multiple modalities simultaneously. Optical imaging, functional MRI, and PET scanning all can be correlated. This hybridization enhances our ability to characterize physiology and pathologies. Thus, imaging can be used to assay the effects of therapeutic treatments on pathologies as well as be used to diagnose pathologies to inform the therapeutics.
Elias A. Zerhouni, M.D.
Director
National Institutes of Health
There’s no doubt that from the standpoint of imaging scientists, the past 30 years have been extraordinary. In this period of time the field has advanced tremendously, both in clinical medicine and in many related areas. Just think about the top five innovations that have dramatically changed the practice of medicine. Imaging can claim three: computed tomography, magnetic resonance imaging and minimally invasive interventional techniques.
I see imaging science playing an equally, if not larger, role in advancing the medical sciences over the next 25 years. How can we use imaging as a strategic tool for biological discovery, as well as a means to translate those discoveries into patient care?
The number one challenge today is biological complexity. Research over the past decade and a half has shown us that biological systems are extremely redundant, very adaptive, and that they appear to act as scale-free networks. To make further progress in science and medicine, we’re going to have to understand how these complex networks function. We will need to understand how molecules interact and how information is transmitted at the fundamental level.
Thus, imaging is central to future progress, because we cannot look at a complex interacting system with the destructive methods that are common today. We need to use research techniques that preserve the sample, not destroy it, and we also need to use much more quantitative approaches.
We have to look at events that occur on a very short time scale and high spatial and temporal resolution is necessary to be able to do this. That’s imaging: extracting spatially and temporally resolved information. It’s not just structure or anatomy. Rather, imaging captures information at all physical scales, from mapping brain function to using crystallography to find out exactly how a molecule latches onto an enzyme to block it or stimulate it.
Innovation in imaging is heavily dependent on interdisciplinary interactions, simply because developing the science of imaging requires a great mastery of physics. Getting different fields to interact in a positive way is, in my view, the core challenge for NIH’s scientific support of imaging research.
I believe these are some of the challenges we must address in order to transform medicine in the next 25 years, and I believe it is critical that we transform medicine. It is important that we shift from an interventional paradigm that relies on treating disease after it has already struck a patient, to an era in which we can intervene and identify a person at risk before his or her symptoms appear.
To do that, we need the ability to explore the human body non-invasively, and the only science that can do this, really, is medical imaging at all scales. Through improvements in imaging, we can understand how pathobiology evolves and intervene much earlier. Medicine of the future will be predictive, personalized and preemptive, and imaging will play an important role in catalyzing a shift from the palliative medicine of today. ♦