It is an exciting time for pulmonary medicine. Genetic and molecular techniques are providing deeper insight into disease mechanisms. As a consequence, diseases are increasingly defined by genetic, molecular, and physiologic paradigms, rather than the traditional constructs of syndromes and anatomy. These changes bring new insight and understanding to the field of pulmonary medicine, and clinicians armed with this knowledge are placing new demands on their diagnostic tools. As the definition of diseases change, physicians will become increasingly dependent on gauges of lung function, metabolism, and genetic expression to diagnose and manage their patients. These observations hold true for the demands of pulmonary imaging as well, and it is imperative that the field adapts and integrates into the new diagnostic landscape if it is to remain relevant.
Fortunately, the field of lung imaging is well suited to meet this challenge. Over the past few years we have noticed a diverse group of researchers independently building collective knowledge that is advancing the field in a positive direction. This knowledge, however, is more amorphous and less directed than that in other specialties. We believe that this is due to the lack of a formal mechanism for exchanging ideas and promoting dialogue. To help foster the specialty, we held the 2006 International Workshop on Functional Lung Imaging at Penn, University of Pennsylvania, Philadelphia, PA. The idea was to bring together individuals, from as broad a spectrum of backgrounds as possible, interested in a common topic of functional and metabolic lung imaging for a series of formal and informal discussions. Our hope was to educate, inspire, and promote synergy among researchers. The workshop was an overwhelming success with more than 50 academic faculty, 46 invited lecturers, 150 registrants, and a large Internet audience.
We have decided to publish highlights of the 2006 workshop in this special issue of Academic Radiology . This special issue is devoted to the work presented by twelve of the speakers at the 2006 workshop and were chosen to illustrate the diversity and breadth of pulmonary imaging research. Some researchers in functional pulmonary imaging are combining strategies and/or imaging modalities in their study of respiratory diseases: Patz et al. ( ) and Hersman et al. ( ) independently present novel polarizers capable of producing xenon-129 for human applications; Conradi et al. ( ) discuss the hyperpolarized 3 He long-range diffusion coefficient as a sensitive maker for pulmonary tissue destruction due to emphysema; Mugler et al. ( ) discuss the diffusion time in helium-3 ( 3 He) magnetic resonance imaging (MRI) and its relation to lung microstructure; Fain et al. ( ) utilize hyperpolarized 3 He MRI and multidetector row computed tomography (MDCT) to assess regional distribution of lung disease in presence of asthma; and Suter et al. ( ) present a method for incorporating data from MDCT into images from digital white light and fluorescence bronchoscopy to generate a “single synergistic description of the airways.” Others who spoke at the 2006 workshop presented ideas that could enrich and improve the current state of functional pulmonary imaging. Parraga et al. ( ) present data that may alter the way in which 3 He images of elderly subjects are interpreted, and Tsai et al. ( ) use hyperpolarized 3 He MRI to investigate the effects of body position and gravity on lung function and measurements of critical parameters, such as pulmonary ventilation and perfusion. Still other investigators at the workshop discussed expanding the applications of functional pulmonary imaging. Emami et al. ( ) show a new method for assessment of early emphysema using measurements of regional ventilation through the same technology. Tzeng et al. ( ) study the utility of hyperpolarized 3 He MRI in investigating the effects of asthma on the diameter of human airways, and Shroeder et al. ( ) discuss a new model for the kinetics of 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG), a radiotracer used in positron emission tomographic imaging. Finally Guyer et al. ( ) assess reliable methods to extract functional lung parameters from noisy MR images.
We believe the 2006 International Workshop on Pulmonary Imaging helped advance functional pulmonary imaging by facilitating the exchange of ideas within the field. This special issue of Academic Radiology is intended as a continuation of the forum established at the Workshop. We wish to further disseminate the shared information and to invite others to participate in our ongoing conversation on functional pulmonary imaging. We hope the readers of Academic Radiology will join us in this extended forum, believing that the interdisciplinary sharing of knowledge and expertise will accelerate innovation in thoracic imaging, critical to its changing role in the new era of personalized medicine. It is also informative to compare the papers from this issue to those presented in the November 2005 special issue of Academic Radiology on functional lung imaging, which was devoted to papers presented at the 2004 Workshop on functional lung imaging. This includes interesting works by Simon et al. ( ), Coxson et al. ( ), Mentore et al. ( ), Conradi et al. ( ), and Fischer et al. ( ). The contrast between the two issues clearly illustrates the evolutionary nature of this field and bright future ahead. We hope you enjoy this issue and invite interested individuals to participate in the next workshop to be held at the University of Pennsylvania in 2009.
References
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