CAMRT Radiography Practice Exam

What is the purpose of the air gap technique in radiography?

1. To increase patient comfort

2. To decrease scatter and increase image contrast

3. To reduce exposure time

4. To enhance image resolution

The correct answer is: To decrease scatter and increase image contrast

The purpose of the air gap technique in radiography is to decrease scatter and increase image contrast. This technique involves positioning the image receptor a certain distance from the patient, creating a space (or "gap") filled with air. Scatter radiation, which occurs when primary x-rays interact with the tissues of the patient, can degrade the quality of the resulting image by adding unwanted noise. By increasing the distance between the patient and the image receptor, some of the scattered rays are absorbed or dispersed before they reach the receptor, leading to clearer images with better contrast. In the context of radiography, maintaining high image quality is essential for accurate diagnoses, and the air gap technique helps achieve that by specifically targeting scatter radiation mitigation. This technique is especially useful in certain imaging situations, such as in systems without a grid, where increasing the distance can enhance overall image quality without relying on additional equipment. While increasing patient comfort, reducing exposure time, and enhancing image resolution are important considerations in radiography, they are not the primary objectives of the air gap technique. The main focus remains on minimizing scatter and thereby improving the contrast of the image captured.