Simulation of the image quality of an a-Si flat x-ray detector system in low-dose fluoroscopic applications

Tom J. C. Bruijns; Thijs Adriaansz; Arnold R. Cowen; Andrew G. Davies; Stephen M. Kengyelics; Kourosh Kiani; Han Kroon; Hans A. Luijendijk

doi:10.1117/12.384484

25 April 2000 Simulation of the image quality of an a-Si flat x-ray detector system in low-dose fluoroscopic applications

Tom J. C. Bruijns, Thijs Adriaansz, Arnold R. Cowen, Andrew G. Davies, Stephen M. Kengyelics, Kourosh Kiani, Han Kroon, Hans A. Luijendijk

Author Affiliations +

Proceedings Volume 3977, Medical Imaging 2000: Physics of Medical Imaging; (2000) https://doi.org/10.1117/12.384484
Event: Medical Imaging 2000, 2000, San Diego, CA, United States

Abstract

One of the issues in (alpha) -Si:H X-ray detectors is signal to noise ratio for low dose fluoroscopic applications. An optimized sensitivity of the X-ray detection system together with low and isotropic system noise characteristics are primary pre-conditions needed for maximum image quality. However, in spite of high DQE numbers of this Flat Detector technology in radiological and fluoroscopic application areas, a SNR for low dose fluoroscopy is found, which is inferior to that found with Image Intensifier-TV based systems. The problem area is a small dose range, producing gray levels just above absolute dark. Except for the dark level, these levels can (dependent on the application area) contain clinically relevant information. Since scatter affects the darker parts of the relevant image areas there will be noise in those areas, caused by X-ray quantum statistics and readout noise. The objective of the simulations is to investigate the influence of the various system noise components on the image quality. A level of system noise can be found where the subjective image quality is mainly determined by the X-ray quantum statistics and where the readout noise does not necessarily have to be invisible in totally dark parts. The simulation concerns a threshold contrast detail detectability (TCDD) observation test, where observers score discs of various diameter and absorption in an image sequence (being a fixed scene of the test object with (temporal) X-ray noise and system noise). The dynamic sequence is based upon total simulation, i.e. the test object as well as the X-ray noise and the system noise components were simulated. To verify the simulations also an image sequence was acquired on a Flat Detector system. The observations are done at various dose levels, with and without post processing to obtain noise reduction like it is used in clinical practice for this kind of system. The sequences are observed on a medical CRT display.

Citation Download Citation

Tom J. C. Bruijns, Thijs Adriaansz, Arnold R. Cowen, Andrew G. Davies, Stephen M. Kengyelics, Kourosh Kiani, Han Kroon, and Hans A. Luijendijk "Simulation of the image quality of an a-Si flat x-ray detector system in low-dose fluoroscopic applications", Proc. SPIE 3977, Medical Imaging 2000: Physics of Medical Imaging, (25 April 2000); https://doi.org/10.1117/12.384484

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available