System performance of phosphor screen coupled CMOS imager for long-term radiation exposure

Kim, Kwang Hyun

doi:10.1016/j.nima.2009.03.157

Cited by 1 publication

(3 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The image creation procedure involves X-ray absorption in the image detector, creation of secondary quanta (electrons in direct conversion detectors or optical photons in indirect conversion detectors [ 9 , 13 , 17 , 31 , 32 , 33 , 34 , 35 , 36 ]), the spread of the secondary quanta to the output and the interaction in its electronic part. Therefore, the final image is characterized by visual unsharpness (i.e., blur) in object details and noise due to the statistical properties of signal propagation [ 9 , 10 , 11 , 12 , 13 , 14 , 31 ]. The blur can be described in the spatial frequency domain via the MTF .…”

Section: Methodsmentioning

confidence: 99%

“…In addition, dual energy imaging methodologies in mammographic imaging with novel detectors have been reported [ 7 , 8 ]. X-ray detectors are evaluated either experimentally or by using theoretical models [ 9 , 10 , 11 , 12 , 13 ]. In each case, imaging metrics, such as the modulation transfer function ( MTF ) showing image sharpness, the normalized noise power spectrum ( NNPS ) showing image noise and the detective quantum efficiency (DQE) showing signal-to-noise transfer, are evaluated using standardized protocols [ 11 , 14 , 15 , 16 , 17 , 18 ].…”

Section: Introductionmentioning

confidence: 99%

“…In addition, physical phantoms may be used to determine other parameters such as contrast-to-noise ratio and detectability of lesions in noisy background [ 10 , 11 , 12 , 19 , 20 , 21 , 22 ]. This type of evaluation is important since the visibility of objects of different contrast and dimensions can lead to the optimization of the exposure and detector readout conditions per clinical examination, thus regulating the dose to the patient.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A Novel Method to Model Image Creation Based on Mammographic Sensors Performance Parameters: A Theoretical Study

Kalyvas

Chamogeorgaki

Michail

et al. 2023

Sensors

View full text Add to dashboard Cite

Background: Mammographic digital imaging is based on X-ray sensors with solid image quality characteristics. These primarily include (a) a response curve that yields high contrast and image latitude, (b) a frequency response given by the Modulation Transfer Function (MTF), which enables small detail imaging and (c) the Normalize Noise Power Spectrum (NNPS) that shows the extent of the noise effect on image clarity. Methods: In this work, a methodological approach is introduced and described for creating digital phantom images based on the measured image quality properties of the sensor. For this purpose, a mathematical phantom, simulating breast tissue and lesions of blood, adipose, muscle, Ca and Ca(50%)-P(50%) was created by considering the corresponding X-ray attenuation coefficients. The simulated irradiation conditions of the phantom used four mammographic spectra assuming exponential attenuation. Published data regarding noise and blur of a commercial RadEye HR CMOS imaging sensor were used as input data for the resulting images. Results: It was found that the Ca and Ca(50%)-P(50%) lesions were visible in all exposure conditions. In addition, the W/Rh spectrum at 28 kVp provided more detailed images than the corresponding Mo/Mo spectrum. Conclusions: The presented methodology can act complementarily to image quality measurements, leading to initial optimization of the X-ray exposure parameters per clinical condition.

show abstract