"nonneoplastic" - 1 õppematerjal

Rational Use of Diagnostic Tests

Often, several diagnostic modalities can be used to seek a diagnosis in a symptomatic patient. Each test has unique characteristics of which a clinician should be aware. For example, both thoracic radiographs and computed tomography (CT) scan can be used to evaluate pulmonary metastases. CT scan is the more sensitive modality due to superior contrast resolution and diminished anatomic superimposition.[3,4] CT may be less specific though, since it detects more lesions, many of which may be nonneoplastic. It would make sense to use CT scan as a screening test. However, it is less readily available, more expensive, and requires general anesthesia, which increases risk to the patient and cost to the owner. Therefore, radiographs are still more commonly used. However, situations exist where CT scan should be strongly considered. For example, prior to thoracotomy for pulmonary mass excision, CT scan should be recommended to better characterize lymph node size and determine the presence of smaller