What is the difference between fluoroscopy and fluorography

Written by radiologists, for radiologists with plenty of easy-to-follow diagrams to explain complicated concepts. An excellent resource for radiology physics revision. The IITV system is characterised by the ability to convert the input light into a much higher output gain or intensification. The x-ray II tube is a vacuum glass or ceramic envelope surrounded by a metal housing to shield from external light sources and magnetic fields. The degree to which an image is intensified or amplified is given by the brightness gain G brightness which is the ratio of the brightness of the output screen compared to the input screen.

In turn, the minification gain describes how much the brightness has increased due to the demagnification of the image in the II tube. In measuring the ability of the II tube to amplify the signal we are unable to measure the brightness of the input screen, which limits the use of the G brightness. Instead we now use the image intensifier conversion factor G x.

The input screen is maintained at a negative voltage with respect to the anode output screen with a potential difference of 25 kV. This means the electrons produced are accelerated across the II tube and carefully focused on the output screen.

Focusing electrodes are metal rings within the tube that are held at positive voltages with respect to the photocathode. This constrains the electrons in the tube to travel along paths that lead them directly to the output screen, such that the pattern of electron intensities falling on the screen are an exact but minified replica of the pattern intensities on the input screen.

Magnification is achieved electronically with electronic focusing of the electron beam. If a smaller area of the input screen is sampled the image is still shown on the same area of output screen the output image size remains constant. This results in a magnified image. Because less signal is used, the image is less bright and, therefore, a higher dose is needed.

However, as the image is magnified, the resolution is better. Thin layer of silver-activated zinc cadmium sulphide ZnCdS:Ag crystals deposited on the inner surface of the output window that convert the electrons into light photons.

The output image is intensified significantly by the acceleration of the electrons and the minification of the image that occurs in the II tube. The screen is normally mm in diameter and a few micrometres thick. This surface of the output screen is coated in a very thin layer of aluminium that:. This is an optically transparent glass block port through which the intensified light image exits the II tube.

Scatter of light, or halation, in the output window can seriously degrade the contrast of the II output image. Minimising halation can be done with:. A TV camera tube uses an electron beam that scans across, line by line.

The scanning direction is determined by focusing and deflection coils arranged around the outside of the tube. Each pixel in the CCD has an associated electrode. This is due to three issues: the equipment, the examination method and the non-use of fluoroscopy. DAP values from spot films are comparable with the Persliden results 13 ; this may be related to the use of computed radiography in our study and digital radiology in the Persliden study. This is due to the use of the film-screen combination by the Almen, Mattsson 14 and UK studies.

When comparing the values of this study with those of other studies, it is evident that the digital unit delivers lower radiation doses. However, the authors did state that there was no significant difference in the interpretation of the images between the two types of images.

The result of the present study supports this statement. Therefore, this study suggests that standard VCUG for reflux diagnosis and grading can be replaced with the photographic method. The outcome of this study shows that the examination technique in pediatric radiology is not yet optimized and that the non-optimized procedures contribute to considerable variations in radiation doses for children.

According to our results, the radiation doses received by the parents were similar to background levels. Although the doses received in fluoroscopy are lower than the dose equivalent limit recommended for the general public, exposure should be kept to a minimum, following the ALARA principle.

However, the risk versus benefit of each radiograph is important and must be considered carefully, especially since radiation effects are cumulative. The results of this study show that standard VCUG for reflux diagnosis and grading can be replaced with the photographic method without spot films, although further studies using the same design are warranted.

Quantitative methods for the assessment of patient doses should be implemented in radiology departments. More laboratory and clinical research is necessary to investigate methods for reducing radiation exposure during VCUG. Nepro-Urol Mon;4 3 : DOI: Financial Disclosure: Not stated. National Center for Biotechnology Information , U. Journal List Nephrourol Mon v. Nephrourol Mon.

Published online Jun Author information Article notes Copyright and License information Disclaimer. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

This article has been corrected. See Nephrourol Mon. Abstract Background Imaging of the urinary system is considered to be responsible for significant radiation in children. Objectives This study was conducted to measure and compare the radiation dose in spot films with photofluorography voiding cystourethrography VCUG in children.

Patients and Methods [ Kidney Urinary Unit KUU ] pediatric patients, aged 1 month to 5 years, with symptomatic urinary tract infection were enrolled in the study. Background In the 11th Report on Carcinogens of the United States National Toxicology program, X-irradiation and ionizing irradiation were placed on the list of known human carcinogens 1. Objectives This study was conducted to measure and compare radiation doses in spot films with photofluorography VCUG in children.

Patients and Methods Data were collected from the pediatric radiology department of an academic center Dr. Results We analyzed KUU kidney urinary unit reports for presence or absence of VUR and its grading in spot films the gold standard and photofluorography images. Patient, No. It uses the same technology as an x-ray in order to generate a working image for a doctor to interpret in the process of caring for a patient.

However, it does so in a video capacity, which can open up many other opportunities for its usefulness. The fluoroscope allows the observer to visualize the interior of the body as it moves and functions.

X-ray and fluoroscopy technology are essentially the same, with a few notable differences. They both are powered by electromagnetic radiation for the purpose of obtaining necessary images. Your doctor will make a recommendation based upon the needs of your particular case. If you have any concerns about the risks associated with the process of obtaining the images themselves, or with the logistics surrounding using these technologies, consult with your doctor.

They should be well prepared to assuage any difficulties you might be having with x-rays or fluoroscopy. Create a free Team What is Teams?

Learn more. Fluoroscopy vs. Asked 3 years, 4 months ago. Active 1 year, 11 months ago. Viewed 1k times. Improve this question. Add a comment. Active Oldest Votes.