Brian P. Jacob, David C. Chen, Bruce Ramshaw, Shirin Towfigh (eds.) - The SAGES Manual of Groin Pain-Springer International Publishing (2016)

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Fig. 13.2. A four view series of the lumbar spine combines the traditional two
view series (anteroposterior and lateral) with left and right oblique views.
While the AP and lateral views are sufficient for evaluating for vertebral body
height and alignment, oblique views reveal the “scotty dog” appearance of the
posterior structures, allowing for evaluation of the pedicle ( arrow ), lamina
( asterisk ), pars articularis ( curved arrow ), and facets ( circle ). Spondylolysis,
or interruption of the pars articularis, may predispose to neuroforaminal stenosis
and subsequent neurogenic groin pain.
such as appendicitis and degenerative spine disease in particular benefit
from modern high-resolution multiplanar imaging (Fig. 13.4 ). Other less
common causes of groin pain such as diverticulitis, abdominal aortic
aneurysm, myositis ossificans, adductor tendonitis, prostatitis, and pelvic
inflammatory disease are well visualized by computed tomography,
although full characterization may require follow-up evaluation with
contrast or another imaging modality.
The overall radiation dose of a CT study is a function of the dose
associated with each acquisition, and the total number of acquisitions
needed to generate the three-dimensional attenuation map. Patient factors
such as body width, lean muscle mass, and the presence of intervening
hardware (e.g., spinal fusion, hip arthrodesis, etc.) influence total
dose. Modern technologies such as exposure control and iterative reconstruction
can automatically reduce dose to minimally necessary levels.
For comparison’s sake, the American College of Radiology (ACR)
maintains a set of Appropriateness Criteria. Their most recent Radiation
Dose Assessment lists a typical abdominal CT as the rough equivalent