Home | | Radiology | Spot Film Devices

Chapter: Basic Radiology : The Physical Basis of Diagnostic Imaging

| Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail |

Spot Film Devices

The aforementioned image recording methods merely store the image recorded by the TV camera.

Spot Film Devices

 

The aforementioned image recording methods merely store the image recorded by the TV camera, which is of lower quality than a radiographic image and has even poorer resolution than the image appearing on the output phosphor of the image-intensifier tube because of the limita-tions of the TV imaging process. In order to record higher quality images during a fluoroscopic examination, spot film devices are used. The most common device transports a conventional radiographic screen/film cassette to a posi-tion in front of the image intensifier at the push of a button on the fluoroscopic carriage. The x-ray tube is then switched into a radiographic mode (ie, the milliamperage is increased from low mA to 200 to 400 mA to shorten expo-sure time), and a conventional radiographic image is obtained on film. Digital spot films can be obtained by dig-itizing a TV frame from the image intensifier acquired with a short exposure burst at a higher exposure value than that of a single continuous fluoroscopic frame. These produce an image of higher quality (lower noise) than that obtained from the fluoroscopic image.


Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail


Copyright © 2018-2020 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.