EFFECTIVENESS OF RADIOLOGICAL IMAGING TECHNIQUES (X-RAYS, MDCT, AND MRI) FOR DIAGNOSIS OF PELVIC FISTULA: A SYSTEMATIC REVIEW

This study aimed to evaluate the diagnostic performance of different imaging techniques for preoperative detection of pelvic fistula. Imaging and classification of female genital abnormalities considerably pelvic floor fistulas are significant. We conducted a systematic review of the available literature to highlight the effectiveness of different radiological imaging techniques (X-RAY,U/S,CT,MRI) for the diagnosis of different types of pelvic fistulas to see the limitations of conventional scanning and testing over modern imaging techniques and to show the effectiveness of choosing one imaging modality over other depending upon multiple dynamics e.g., site and types of fistula. The controlled and regular research cases (n= 9) available in English from 2011 to 2020 were included in criteria of research. The evidence databases were used for assessment of certain studies analytically by way of PEDro scale and explicated under decision guidelines. In all relevant articles were identified and included in this systematic review. The radiological techniques showed improved diagnostic performance that established the effectiveness of imaging advancement for administration and treatment of pelvic fistula. Conventional methods have less sensitivity and specificity as compared to modern techniques. X-RAY fistulography and ultrasonography has less sensitivity and specifity as compared to CT scan but still found beneficial in the diagnosis of colovaginal, uterovesical fistula and considered as the most basic clue about the existence of a malignant fistula respectively.it is verified that MDCT is the safer accurate and offered more detailed defects in diagnosis of urogenital, urethrorectal, lower urogenital tract fistulas, upper and middle vaginal fistulas colovesical fistulas(along with X-RAY) and prostate symphyseal fistula(along with MRI).It has been concluded that MRI can access colovesical fistulas inherited vaginal fistulas and prostate symphyseal fistulas(along with CT) more efficiently. It has been concluded that diagnostic imaging for all pelvic fistula is useful, to help the physicians, particularly radiologists, in diagnosis of pelvic fistulas. The choice of imaging technique is dependent upon multiple factors. Advanced medical imaging techniques XRAY,MDCT MRI) are considered more recommended choices as compared to conventional imaging.

Download Full-text

Diagnostic Performance of Conventional X-ray for Detecting Foreign Bodies in the Upper Digestive Tract: A Systematic Review and Diagnostic Meta-Analysis

Diagnostics ◽

10.3390/diagnostics11050790 ◽

2021 ◽

Vol 11 (5) ◽

pp. 790

Author(s):

Ta-Wei Yang ◽

Yi-Chung Yu ◽

Yen-Yue Lin ◽

Shih-Chang Hsu ◽

Karen Chia-Wen Chu ◽

...

Keyword(s):

Systematic Review ◽

Diagnostic Accuracy ◽

Digestive Tract ◽

Diagnostic Performance ◽

Meta Analysis ◽

Characteristic Curve ◽

Cochrane Library ◽

X Rays ◽

X Ray ◽

Upper Digestive Tract

Foreign body (FB) ingestion is a common clinical problem in acute settings. Detecting FBs in the upper digestive tract is challenging. The conventional X-ray is usually the first-line imaging tool to detect FBs. However, its diagnostic performance is inconsistent in the literature. In this study, we performed a systematic review and meta-analysis to determine the diagnostic performance of the conventional X-ray for detecting FBs in the upper digestive tract. We conducted a systematic search of PubMed, Embase, Cochrane Library, Web of Science, and Scopus until 1 August 2020. Prospective or retrospective studies investigating the diagnostic accuracy of conventional X-rays for detecting FBs in the upper digestive tract in patients of all ages were included. The Quality Assessment of Studies of Diagnostic Accuracy-2 tool was used to review the quality of included studies. We used a bivariate random-effects model to calculate diagnostic accuracy parameters. Heterogeneity was assessed using I2 statistics. We included 17 studies (n = 4809) in the meta-analysis. Of the 17 studies, most studies were rated as having a high risk of bias. Conventional X-rays had a pooled sensitivity of 0.58 (95% confidence interval [CI] = 0.36–0.77, I2 = 98.52) and a pooled specificity of 0.94 (95% CI = 0.87–0.98, I2 = 94.49) for detecting FBs in the upper digestive tract. The heterogeneity was considerable. The area under the summary receiver operating characteristic curve was 0.91 (95% CI = 0.88–0.93). Deek’s funnel plot asymmetry test results revealed no significant publication bias (p = 0.41). The overall sensitivity and specificity of conventional X-rays were low and high, respectively, for detecting FBs in the upper digestive tract. Hence, conventional X-rays to exclude patients without upper FBs in the digestive tract are not recommended. Further imaging or endoscopic examinations should be performed for at-risk patients.

Download Full-text

Studies of metaphase chromosomes in the scanning transmission x-ray microscope: Image fidelity, radiation damage and specimen preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129826 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1038-1039

Author(s):

Shawn Williams ◽

Xiaodong Zhang ◽

Susan Lamm ◽

Jack Van’t Hof

Keyword(s):

Visible Light ◽

Radiation Damage ◽

Cross Section ◽

Imaging Techniques ◽

Dose Range ◽

Specimen Preparation ◽

X Rays ◽

Metaphase Chromosomes ◽

X Ray ◽

Scanning Transmission

The Scanning Transmission X-ray Microscope (STXM) is well suited for investigating metaphase chromosome structure. The absorption cross-section of soft x-rays having energies between the carbon and oxygen K edges (284 - 531 eV) is 6 - 9.5 times greater for organic specimens than for water, which permits one to examine unstained, wet biological specimens with resolution superior to that attainable using visible light. The attenuation length of the x-rays is suitable for imaging micron thick specimens without sectioning. This large difference in cross-section yields good specimen contrast, so that fewer soft x-rays than electrons are required to image wet biological specimens at a given resolution. But most imaging techniques delivering better resolution than visible light produce radiation damage. Soft x-rays are known to be very effective in damaging biological specimens. The STXM is constructed to minimize specimen dose, but it is important to measure the actual damage induced as a function of dose in order to determine the dose range within which radiation damage does not compromise image quality.

Download Full-text

An x-ray microprobe based upon a close-coupled focal-spot / glass capillary arrangement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133424 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1758-1759

Author(s):

D. A. Carpenter ◽

M. A. Taylor

Keyword(s):

Imaging Techniques ◽

Fluorescence Analysis ◽

High Sensitivity ◽

Specimen Preparation ◽

X Rays ◽

Glass Capillary ◽

Close Coupling ◽

X Ray ◽

Point To Point ◽

Beam Damage

The development of intense sources of x rays has led to renewed interest in the use of microbeams of x rays in x-ray fluorescence analysis. Sparks pointed out that the use of x rays as a probe offered the advantages of high sensitivity, low detection limits, low beam damage, and large penetration depths with minimal specimen preparation or perturbation. In addition, the option of air operation provided special advantages for examination of hydrated systems or for nondestructive microanalysis of large specimens.The disadvantages of synchrotron sources prompted the development of laboratory-based instrumentation with various schemes to maximize the beam flux while maintaining small point-to-point resolution. Nichols and Ryon developed a microprobe using a rotating anode source and a modified microdiffractometer. Cross and Wherry showed that by close-coupling the x-ray source, specimen, and detector, good intensities could be obtained for beam sizes between 30 and 100μm. More importantly, both groups combined specimen scanning with modern imaging techniques for rapid element mapping.

Download Full-text

Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽

10.3390/s21134554 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4554

Author(s):

Ralph-Alexandru Erdelyi ◽

Virgil-Florin Duma ◽

Cosmin Sinescu ◽

George Mihai Dobre ◽

Adrian Bradu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Radiation Dose ◽

Imaging Techniques ◽

Image Resolution ◽

Optical Coherence ◽

X Rays ◽

High Quality ◽

X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

Download Full-text

Spectral Tomography for 3D Element Detection and Mineral Analysis

Minerals ◽

10.3390/min11060598 ◽

2021 ◽

Vol 11 (6) ◽

pp. 598

Author(s):

Jose R. A. Godinho ◽

Gabriel Westaway-Heaven ◽

Marijn A. Boone ◽

Axel D. Renno

Keyword(s):

Energy Spectrum ◽

3D Imaging ◽

X Rays ◽

3D Images ◽

Characterization Methods ◽

X Ray ◽

Additional Information ◽

Mineral Phases ◽

Spectral Computed Tomography

This paper demonstrates the potential of a new 3D imaging technique, Spectral Computed Tomography (sp-CT), to identify heavy elements inside materials, which can be used to classify mineral phases. The method combines the total X-ray transmission measured by a normal polychromatic X-ray detector, and the transmitted X-ray energy spectrum measured by a detector that discriminates between X-rays with energies of about 1.1 keV resolution. An analysis of the energy spectrum allows to identify sudden changes of transmission at K-edge energies that are specific of each element. The additional information about the elements in a phase improves the classification of mineral phases from grey-scale 3D images that would be otherwise difficult due to artefacts or the lack of contrast between phases. The ability to identify the elements inside the minerals that compose ore particles and rocks is crucial to broaden the application of 3D imaging in Earth sciences research and mineral process engineering, which will represent an important complement to traditional 2D imaging mineral characterization methods. In this paper, the first applications of sp-CT to classify mineral phases are showcased and the limitations and further developments are discussed.

Download Full-text

Classification of Fresh Fractures of the Lunate

Journal of Hand Surgery (European Volume) ◽

10.1016/0266-7681_88_90180-5 ◽

1988 ◽

Vol 13 (4) ◽

pp. 458-462

Author(s):

H. TEISEN ◽

J. HJARBAEK

Keyword(s):

Vascular Anatomy ◽

X Rays ◽

Lunate Bone ◽

X Ray

The X-rays of 17 patients with fresh fractures of the lunate bone have been reviewed. The fractures were classified according to their radiological appearances and according to the vascular anatomy of the lunate. A long term X-ray follow-up examination was performed.

Download Full-text

Truncated Inception Net: COVID-19 Outbreak Screening using Chest X-rays

10.21203/rs.3.rs-20795/v1 ◽

2020 ◽

Cited By ~ 4

Author(s):

Dipayan Das ◽

KC Santosh ◽

Umapada Pal

Keyword(s):

Neural Network ◽

World Wide ◽

Imaging Techniques ◽

Imaging Systems ◽

Ct Scans ◽

X Rays ◽

X Ray ◽

X Ray Imaging ◽

Proposed Model ◽

Different Types

Abstract Since December 2019, the Coronavirus Disease (COVID-19) pandemic has caused world-wide turmoil in less than a couple of months, and the infection, caused by SARS-CoV-2, is spreading at an unprecedented rate. AI-driven tools are used to identify Coronavirus outbreaks as well as forecast their nature of spread, where imaging techniques are widely used, such as CT scans and chest X-rays (CXRs). In this paper, motivated by the fact that X-ray imaging systems are more prevalent and cheaper than CT scan systems, a deep learning-based Convolutional Neural Network (CNN) model, which we call Truncated Inception Net, is proposed to screen COVID-19 positive CXRs from other non-COVID and/or healthy cases. To validate our proposal, six different types of datasets were employed by taking the following CXRs: COVID-19 positive, Pneumonia positive, Tuberculosis positive, and healthy cases into account. The proposed model achieved an accuracy of 99.96% (AUC of 1.0) in classifying COVID- 19 positive cases from combined Pneumonia and healthy cases. Similarly, it achieved an accuracy of 99.92% (AUC of 0.99) in classifying COVID-19 positive cases from combined Pneumonia, Tuberculosis and healthy CXRs. To the best of our knowledge, as of now, the achieved results outperform the existing AI-driven tools for screening COVID-19 using CXRs.

Download Full-text

Optimization of the energy for Breast monochromatic absorption X-ray Computed Tomography

Scientific Reports ◽

10.1038/s41598-019-49351-2 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Pasquale Delogu ◽

Vittorio Di Trapani ◽

Luca Brombal ◽

Giovanni Mettivier ◽

Angelo Taibi ◽

...

Keyword(s):

Computed Tomography ◽

Imaging Techniques ◽

Fixed Dose ◽

X Rays ◽

Reconstruction Algorithms ◽

Contrast Resolution ◽

X Ray ◽

X Ray Imaging ◽

X Ray Computed ◽

Dose Levels

Abstract The limits of mammography have led to an increasing interest on possible alternatives such as the breast Computed Tomography (bCT). The common goal of all X-ray imaging techniques is to achieve the optimal contrast resolution, measured through the Contrast to Noise Ratio (CNR), while minimizing the radiological risks, quantified by the dose. Both dose and CNR depend on the energy and the intensity of the X-rays employed for the specific imaging technique. Some attempts to determine an optimal energy for bCT have suggested the range 22 keV–34 keV, some others instead suggested the range 50 keV–60 keV depending on the parameters considered in the study. Recent experimental works, based on the use of monochromatic radiation and breast specimens, show that energies around 32 keV give better image quality respect to setups based on higher energies. In this paper we report a systematic study aiming at defining the range of energies that maximizes the CNR at fixed dose in bCT. The study evaluates several compositions and diameters of the breast and includes various reconstruction algorithms as well as different dose levels. The results show that a good compromise between CNR and dose is obtained using energies around 28 keV.

Download Full-text

K-edge Subtraction Computed Tomography with a Compact Synchrotron X-ray Source

Scientific Reports ◽

10.1038/s41598-019-49899-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Stephanie Kulpe ◽

Martin Dierolf ◽

Benedikt Günther ◽

Madleen Busse ◽

Klaus Achterhold ◽

...

Keyword(s):

Computed Tomography ◽

Contrast Agent ◽

Imaging Techniques ◽

X Rays ◽

Synchrotron Source ◽

X Ray ◽

Inverse Compton Scattering ◽

Inverse Compton ◽

X Ray Computed ◽

Compact Light Source

Abstract In clinical diagnosis, X-ray computed tomography (CT) is one of the most important imaging techniques. Yet, this method lacks the ability to differentiate similarly absorbing substances like commonly used iodine contrast agent and calcium which is typically seen in calcifications, kidney stones and bones. K-edge subtraction (KES) imaging can help distinguish these materials by subtracting two CT scans recorded at different X-ray energies. So far, this method mostly relies on monochromatic X-rays produced at large synchrotron facilities. Here, we present the first proof-of-principle experiment of a filter-based KES CT method performed at a compact synchrotron X-ray source based on inverse-Compton scattering, the Munich Compact Light Source (MuCLS). It is shown that iodine contrast agent and calcium can be clearly separated to provide CT volumes only showing one of the two materials. These results demonstrate that KES CT at a compact synchrotron source can become an important tool in pre-clinical research.

Download Full-text

NuSTAR reveals that the heavily obscured nucleus of NGC 2785 was the contaminant of IRAS 09104+4109 in the BeppoSAX/PDS hard X-rays

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833805 ◽

2018 ◽

Vol 619 ◽

pp. A16

Author(s):

C. Vignali ◽

P. Severgnini ◽

E. Piconcelli ◽

G. Lanzuisi ◽

R. Gilli ◽

...

Keyword(s):

X Rays ◽

X Ray ◽

Star Forming ◽

Physical Description ◽

Enhanced Sensitivity ◽

X Ray Imaging ◽

First Time ◽

In Virtue Of

Context. The search for heavily obscured active galactic nuclei has been revitalized in the last five years by NuSTAR, which has provided a good census and spectral characterization of a population of such objects, mostly at low redshift, thanks to its enhanced sensitivity above 10 keV compared to previous X-ray facilities, and its hard X-ray imaging capabilities. Aims. We aim at demonstrating how NGC 2785, a local (z = 0.009) star-forming galaxy, is responsible, in virtue of its heavily obscured active nucleus, for significant contamination in the non-imaging BeppoSAX/PDS data of the relatively nearby (≈17′) quasar IRAS 09104+4109 (z = 0.44), which was originally mis-classified as Compton thick. Methods. We analyzed ≈71 ks NuSTAR data of NGC 2785 using the MYTorus model and provided a physical description of the X-ray properties of the source for the first time. Results. We found that NGC 2785 hosts a heavily obscured (NH ≈ 3 × 1024 cm−2) nucleus. The intrinsic X-ray luminosity of the source, once corrected for the measured obscuration (L2−10keV ≈ 1042 erg s−1), is consistent within a factor of a few with predictions based on the source mid-infrared flux using widely adopted correlations from the literature. Conclusions. Based on NuSTAR data and previous indications from the Neil Gehrels Swift Observatory (BAT instrument), we confirm that NGC 2785, because of its hard X-ray emission and spectral shape, was responsible for at least one third of the 20–100 keV emission observed using the PDS instrument onboard BeppoSAX, originally completely associated with IRAS 09104+4109. Such emission led to the erroneous classification of this source as a Compton-thick quasar, while it is now recognized as Compton thin.

Download Full-text