Imaging

The reason for great emphasis on physical signs in the past was the absence of confirmatory imaging techniques. Because of the facility with which these facilities confirm or refute a physical sign, care in their interpretation is rarely taken. Yet, it is physical signs which may lead to a diagnosis, and the constant observation of the patient can delineate changes that are helpful to management.
Most physical signs can be confirmed by ultrasonography, plain radiography, CT or MRI. It is important to be aware of the appropriate test. If a swelling has been defined an ultrasound scan will usually confirm or refute the claim. It will define whether the swelling is solid or cystic, and whether it is aneurysmal, particularly with the aid of Doppler imaging. Biopsy using ultrasonography or CT guidance will give histological confirmation of the nature of the swelling (Fig. 1.9). Plain radiographs will define bony changes and fractures (Fig. 1.10), and gas shadows, such as in abdominal distension. MRI will define abnormalities in joints (Fig. 1.11) and within the skull, whereas CT, particularly with contrast enhancement, will outline solid organs (Fig. 1.12).
Imaging, to reach its full diagnostic potential, must be used correctly, and thus requires study within each surgical discipline.