Advanced Patient Assessment Practice Exam

Which of the following forms of radiologic assessment is most useful for studying the distribution of ventilation and perfusion and the effects that diseases may have on these two important functions?

1. Pulmonary angiography

2. Lung scanning

3. MRI

4. CT scanning

The correct answer is: Lung scanning

Lung scanning, particularly in the form of ventilation-perfusion (V/Q) scans, is specifically designed to assess both the ventilation (airflow) and perfusion (blood flow) in the lungs. This dual evaluation is critical in diagnosing and managing conditions such as pulmonary embolism, chronic obstructive pulmonary disease (COPD), and other pulmonary disorders. The technique typically involves the use of radioactive isotopes to visualize areas of the lungs, allowing for a detailed examination of how well air and blood are distributed throughout the lung tissue. The utility of lung scanning stems from its ability to highlight discrepancies between air and blood flow. For instance, in the case of a pulmonary embolism, which can obstruct blood flow to a portion of the lung, a V/Q scan can show areas where there is adequate ventilation but reduced or absent perfusion, indicating a mismatch due to the blockage. Other radiologic assessment methods, while valuable, do not provide the same combined insights into ventilation and perfusion. Pulmonary angiography focuses primarily on the blood vessels of the lungs, MRI is less common in pulmonary evaluation due to limitations in assessing airflow and blood flow, and CT scanning is more suited for structural imaging rather than functional assessment of ventilation and perfusion. Therefore, lung