Dr. Gotway is an Assistant Professor of Radiology at the
University of California, San Francisco and Chief of Thoracic
Imaging at San Francisco General Hospital, San Francisco,
CA.
The technological aspects of radiology have been increasing
rapidly in recent years. With the advent of helical CT a decade
ago, it became possible to acquire image datasets in a single
breath hold, thus eliminating misregistration artifacts. The
ability to acquire an entire volume of tissue made
three-dimensional imaging a possibility, and the sophistication and
utility of such techniques have proliferated tremendously as a
result. Additionally, as CT became faster, it became possible to
coordinate the scan acquisition parameters with the administration
of the intravenous contrast bolus, making noninvasive vascular
imaging with CT a reality.
Advances in CT technology have again taken a giant leap forward
with the introduction of multidetector-row helical CT technology.
Four channel multidetector-row helical CT scanners provide nearly
three times the volume coverage as single-detector systems, without
compromising image quality. In fact, the quality of imaging,
including multiplanar and volumetric reconstructions, is likely to
be superior with multidetector systems compared with
single-detector scanners. However, this new technology comes with a
price. Radiologists must increase their familiarity with the
technical aspects of helical CT acquisitions to realize the promise
of improved image quality with these new systems. This is
particularly true of vascular applications, such as the imaging of
aortic diseases or pulmonary embolism. In this issue, we will
address the helical CT evaluation of aortic diseases, with special
emphasis on the scan acquisition parameters and some of the
pitfalls that result from the techniques applied in this clinical
setting.
Just as radiologic technology has advanced in recent years, so
has the ability of the pathologist to provide increasingly precise
tissue characterization. Advances in histopathologic techniques has
lead to a fundamental re-thinking of many diseases; nowhere is this
more true than in the field of interstitial lung diseases. The
original classification of interstitial diseases has been modified
recently, and, just as many are beginning to catch up, the names
may be changing again! Fortunately, the imaging manifestations may
be slightly more durable. Thus, in addition to aortic imaging with
helical CT, in this issue we also revisit the imaging of diffuse
lung diseases, with special emphasis on interstitial pneumonias.
The imaging of diffuse lung diseases is an extensive and complex
topic and cannot be addressed adequately in a single review
article. However, many excellent references are provided, and I
hope both of these articles stimulate interest and provide a
foundation for further reading.