American Society for Nondestructive Testing (ASNT) Radiographic Testing Practice Test

The correct choice highlights that limited brightness and large grain size of fluoroscopic screens are serious obstacles to high-intensity fluoroscopy.

Fluoroscopy relies on the interaction of X-rays with a fluorescent screen to create real-time images of dynamic processes within the body. The brightness of the images produced is crucial for effective visualization. Limited brightness can impair the ability to see fine details, leading to potential diagnostic errors.

Moreover, the grain size of the fluorescent screen refers to the size of the crystals used in the imaging process. Larger grain sizes can result in a grainier image, which reduces the overall resolution. This decrease in clarity can hinder the effectiveness of fluoroscopic examinations, especially in scenarios that require high precision, such as detecting small lesions or subtle changes in tissue.

These two factors combined make it challenging to achieve high-quality images during fluoroscopic procedures, which is why they qualify as serious obstacles.