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Radiographic evaluation of the prevertebral space

The prevertebral space as seen on the lateral soft tissue X‐ray is discussed. Variations of normal in the child and adult are reviewed. Normal anatomy may give a false impression of pathology such as air in the ear canal, lung apices, and cervical esophagus. Overlying shadows of other structures, namely, the ear, styloid, stylohyoid ligament, calcified anterior arch of the atlas in a child, calcification in the cricoid signet and cartilago triticea also may be confusing. Physiological changes with crying or swallowing in the child at times appear as pathology. The primary pathological changes seen on X‐ray are air in the tissue spaces, foreign bodies, tumor formation, erosion or proliferation of bone, fractures, deformities of the spine such as reversal of the normal curvature or slippage of the vertebrae, and displacement of the fat line. It must be kept in mind that X‐rays are only one additional tool for making a diagnosis and cannot be substituted for a thorough history and physical examination.