How is Low-Dose Screening CT different from Diagnostic Chest CT?
Low-Dose Spiral Screening CT is designed to replace the chest x-ray in screening asymptomatic patients for pulmonary nodules. The low-dose technique is ideal to evaluate the lung parenchyma for nodules, but is not intended to screen for abnormalities elsewhere in the chest, such as the aorta, heart, lymph nodes, or bones. Like screening mammography, it is important to minimize the amount of radiation exposure in asymptomatic patients. No intravenous contrast is used. Like many other screening tests, many insurance companies will not pay for this exam, although in the future in high-risk patients this situation will hopefully change. The cost of a Low-Dose Screening CT exam is less than half of that for a Diagnostic Chest CT exam. Diagnostic Spiral Chest CT scans are almost always performed to further evaluate an abnormal finding on chest x-ray or to evaluate the chest in certain specific disease conditions. Unlike a low-dose screening exam, which evaluates only the lung parenchymal tis
