When I was first approached about the possibility of writing this Core Curriculum: Cardiopulmonary Imaging textbook, I felt it was an honor, but also realized I could not do it alone. I knew immediately that it would only be possible with the expertise, wisdom, and editorial excellence that Dr. Barry Gross possesses, and am very grateful that he agreed to coauthor this text. My first month as a resident was on thoracic radiology, and his teachings at the alternator still echo in my mind when I work with students, residents and fellows to this day. (In fact, recently I was listening to him work with a resident and students at the PACS workstation, and wished I could sit there again!) Not long after my chest rotation many of the faculty that I worked with left the university, and the difference this made in the quality of the educational experience was striking. Fortunately, by my second month on thoracic radiology, Dr. William Martel had recruited Dr. Melvin Figley to spend a few months here while the chest group was rebuilt. Another outstanding month! I was sold on thoracic radiology as a career! I hope, with this textbook, similarly to “sell” thoracic radiology to radiology residents in training (and even to medical students who haven’t yet chosen radiology as a career!).
We begin this textbook with normal thoracic anatomy and basic physiology, illustrated predominantly with multi-detector CT reconstructions. This is followed by material on the imaging modalities that are commonly applied to the thorax. Given the complexity of the modern CT and MR machines of today, an understanding of how they work, and how changes in acquisition parameters impact the end product (images) are critical to obtaining high quality examinations that are not just general examinations, but are tailored to the clinical question. In 10 years we have gone from having 2 or 3 thoracic CT protocols, to over a dozen. An understanding of our complex imaging equipment comes before instruction in how to recognize normal and abnormal, as well it should. We also emphasize how to recognize imaging artifacts that may simulate disease and how to protocol and monitor examinations for quality. Still, even in 2003 it all comes back to the chest radiograph. We provide practical tips on how to approach the interpretation of the chest radiograph as well as guidance on preparing radiology reports, which are the tangible product of what we do as radiologists and (we hope) a true reflection of what we found and what it may mean. Chest radiographic examinations (or images now that we nearly a fully digital department) are the most common single radiologic test performed, with estimates that 30 to 70 percent of radiologic exams are chest radiographs depending on the practice setting. They are the most commonly interpreted examinations by radiologists. One of the most common ways that radiologists interact with referring physicians is through the reports and consultations generated by these examinations. While on the surface chest radiographs appear to be “simple” to interpret, interpretation may involve subtle displacement of a line, interface or shadow, subtle opacity, or slight change from a prior study. In contrast, on examinations such as CT and MR the anatomy and abnormalities are displayed with greater anatomic resolution and less overlap of structures, and can be viewed not only axially, but with multiplanar and advanced processing techniques, making them in some ways easier to interpret.
Thoracic radiology has come a long way in the last ten to fifteen years, when it was dominated by the hard copy chest radiograph. Today, HRCT, helical CT for pulmonary emboli, CT and MR angiography and cardiac imaging, and PET scanning for lung nodules and cancer staging are mature techniques, widely disseminated in practice. Ten years ago we did perhaps eight to ten dedicated chest CT scans a day. Now, it is not unusual to do thirty to forty in a day. Thoracic radiology is also better known as cardiopulmonary radiology. In fact, the American Board of Radiology uses the term “cardiopulmonary” for one of the ten examination sections of the oral board examination in diagnostic radiology. In recognition of this, we chose to call this textbook Cardiopulmonary Imaging. We have included not only traditional thoracic radiology topics, such as lung cancer, thoracic infections, mediastinal masses, the airway, pleural disease and interstitial and obstructive lung diseases, but also have included the cardiovascular radiology aspects of cardiopulmonary radiology, in recognition of how important this material is to “thoracic” radiology. This material can be found within general thoracic chapters such as ICU imaging, and also within dedicated chapters on adult manifestations of congenital heart disease, acquired heart disease, pulmonary vascular disease, and the thoracic aorta.
This textbook, which we hope you will enjoy, learn from and refer to, could not have been completed without many important people. This was a group effort, and we would like to thank every member of the Thoracic Radiology Division at the University of Michigan, Ann Arbor, Michigan, who contributed to the chapters. Those people are Naama Bogot, Philip Cascade, Paul Cronin, Benoit Desjardins, David Jamadar, Aine Kelly, Uwada Murray, Smita Patel, Perry Pernicano, Leslie Quint, and Michael Sneider.
We also want to thank our physician colleagues for their collegial interaction and multidisciplinary approach. We would especially like to recognize Fernando Martinez in Pulmonary Medicine and Mark Orringer, Mark Iannettoni, and Michael Deeb in Thoracic and Cardiothoracic Surgery.
Lastly, we want to thank all the students, residents, and fellows, past and present, who have rotated through thoracic radiology for the excitement, questions and ideas that they bring with them every day, and for sharing in the fun.