Radiographic Techniques, Contrast, and Noise in X-Ray Imaging

Huda, Walter; Abrahams, R Brad

doi:10.2214/ajr.14.13116

Cited by 74 publications

(48 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Furthermore, the contrast indices are decreased by increasing tube's voltage for all setups because the more scatter radiation reaches to the image receptor, the more noise for radiograph will be. Consistent results are achieved by other authors (Huda & Abrahams, 2015;Hendee & Ritenour, 2003;Hobbie & Roth, 2007;Fletcher & McCollough, 2010;Alsleem, 2014) energy is usually associated with higher contrast and vice versa. Suetens (2009) also reported that the higher the contrast is, the lower the useful exposure range is.…”

Section: Image Contrast At Various X-ray Energy (Kvp)supporting

confidence: 87%

See 1 more Smart Citation

Effect of Backscattered Radiation on X-Ray Image Contrast

Naji¹,

Jaafar²,

Ali³

et al. 2017

APR

View full text Add to dashboard Cite

This paper assesses the effect of backscattered radiation on X-ray image contrast by evaluating the effect of backscatter reduction on X-ray image contrast. Contrast test tool RMI Densitometer, and different types of fabricated anti backscattered grids have been utilized in this study. The measurements are recorded at different exposure parameters such as X-ray tube peak voltage (kVp), and X-rays intensities (mAs). For each exposure, the contrast of the image is evaluated by measuring the variation in optical densities for aluminium steps wedge. The results showed that the x-ray image contrast can be enhanced by decreasing the amount of backscattered radiation, also the fabricated anti backscattered grids have a remarkable effect in the improvement of X-ray image contrast according to grid's capability in reducing backscattered radiation. In addition, the effectiveness of fabricated grids in improving image contrast depends on the grid's material and the geometrical design, as well as the radiation exposure parameters. The image contrast enhancements increased up to 36% with the use of crossed iron steel grid which placed under the film screen combination during exposure.

show abstract

Section: Image Contrast At Various X-ray Energy (Kvp)supporting

confidence: 87%

“…The difference in X-ray beam intensity through a lesion relative to the normal background is called subject contrast. The appearance of this subject contrast in the resultant radiograph is called image contrast (Huda & Abrahams, 2015).…”

Section: Introductionmentioning

confidence: 99%

Effect of Backscattered Radiation on X-Ray Image Contrast

Naji¹,

Jaafar²,

Ali³

et al. 2017

APR

View full text Add to dashboard Cite

show abstract

“…A large irregular distribution of photons received by the detector will cause a grainy appearance, also called noise. 33,34 Image noise is measured as SNR by calculating ROI values gathered from the images in question. The ROI measurement was placed manually, but with precision, on the left top side of the significant object used in the grading.…”

Section: Discussionmentioning

confidence: 99%

Optimization of Codman® Hakim® adjustable valve radiography

Bremnes

Kubosch

Ween

2017

RadOpen

View full text Add to dashboard Cite

PurposeCerebrospinal fluid shunt valves are important tools in hydrocephalus treatment. Adjustable valves, sensitive to MRI, are onerous. They need be controlled; in case of re-settings. The vendor give advices for the radiographic procedure; however, hospitals use variations. The purpose was to investigate the different variations. MethodEight images consisting combinations of protocol features, were subjectively and anonymous rated for image quality. The panel consisted of 60 professionals; 50 radiographers and 10 radiologists, from two hospitals doing neurosurgery services. Signal-to-noise ratio compared the level of desired signal to the level of background noise.Results 348 scores were distributed onto all eight images, revealing the image quality difference was within acceptance. Options as valve on the head side near to the detector versus far to; differing geometry, use of head bowl versus not use, air-gap versus grids, were favored by both professional groups and at both hospitals in a clear priority image, given 2.5 times scores over average (108/43). Noise, revealed being the strongest indicator for priority of the best image for shunt evaluation.

show abstract

“…adicionales, tales como ruido y artefactos. El ruido se produce por las diferencias de atenuación del haz de rayos X, que producen diferencias de captación de la radiación por los pixeles de la imagen digital, resultando en pixeles más oscuros y otros más claros (31) . El grado de ruido depende de aspectos tales como: a) cantidad de la radiación ionizante usada, es decir, del miliamperaje (31) , b) características técnicas del detector o c) procesado de la imagen digital (13) .…”

Section: Diagnóstico Radiográfico En Odontologíaunclassified

“…El ruido se produce por las diferencias de atenuación del haz de rayos X, que producen diferencias de captación de la radiación por los pixeles de la imagen digital, resultando en pixeles más oscuros y otros más claros (31) . El grado de ruido depende de aspectos tales como: a) cantidad de la radiación ionizante usada, es decir, del miliamperaje (31) , b) características técnicas del detector o c) procesado de la imagen digital (13) . Con relación a los artefactos, estos elementos son producidos por efectos absorcionales (32) , se visualizan en el examen radiográfico digital sin estar presentes en el objeto de estudio, y pueden dificultar el diagnóstico radiográfico de la imagen obtenida (5) .…”

Section: Diagnóstico Radiográfico En Odontologíaunclassified