The use of digital magnification to reduce radiation dose in the cardiac catheter laboratory

2022 ◽  
Vol 95 (1129) ◽  
Author(s):  
Shailesh Dalvi ◽  
Hywel Mortimer Roberts ◽  
Christopher Bellamy ◽  
Michael Rees
Keyword(s):  
Radiation Dose ◽  
In Vitro Study ◽  
Significant Loss ◽  
Image Resolution ◽  
Cardiac Catheter ◽  
X Ray ◽  
Large Screen ◽  
Viewing Screen ◽  
Catheter Laboratory

Objectives: To audit whether using magnification of images by use of a large viewing screen using digital matrix magnification which enlarges the image by 33% without using the X-ray machine zoom magnification protocols on a Siemens Artis Zee X-ray machine in a cardiac catheter laboratory results in a reduction of kerma–area product (KAP) for both diagnostic and interventional procedures. This reduction was predicted in an in vitro study in our laboratory, which has previously shown a 20.4% reduction in KAP. Methods: A retrospective analysis was conducted of the radiation exposure to compare the measured KAP recorded during the period when conventional magnification with automatic brightness and dose control was used on a Siemens Artis Zee X-ray machine with a flat panel detector and when magnification settings were avoided by using a large screen to enlarge and project a non-magnified image by digital magnification. The analysis was carried out for patients having a diagnostic coronary angiogram and those having an interventional coronary procedure. Results: For diagnostic coronary angiograms the median KAP per procedure in the period using conventional magnification was 2124.5 µGy.m2 compared to 1401 µGy.m2 when image matrix magnification was used, a 34% reduction (p < 0.0001). For interventional coronary procedures, the median KAP per procedure in the period using conventional magnification was 3791 µGy.m2 compared to 2568.5 µGy.m2 when image matrix magnification was used, a 32% reduction (p < 0.0001). Conclusion: Avoiding using conventional magnification in the cardiac catheter laboratory and using a large screen to magnify images was associated with a statistically significant greater than 30% reduction in KAP. Advances in knowledge: This paper is the proof in clinical practice of a theoretical conclusion that radiation dose (KAP) is reduced by use of Image matrix magnification using a large viewing screen without the need to use X-ray tube magnification without significant loss of image resolution in interventional cardiology. The same approach will be useful in interventional radiology.

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

Sensors ◽  
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.

Comparison of bivalirudin, enoxaparin, and unfractionated heparin in preventing cardiac catheter thrombosis

2008 ◽  
Vol 100 (10) ◽  
pp. 693-698 ◽  
Author(s):  
Michael Buerke ◽  
Sebastian Schubert ◽  
Iris Reindl ◽  
Thomas Michel ◽  
Baerbel Hauroeder ◽  
...  
Keyword(s):  
Unfractionated Heparin ◽  
Continuous Infusion ◽  
Treatment Strategies ◽  
In Vitro Study ◽  
Coronary Intervention ◽  
Thrombin Inhibitor ◽  
P Value ◽  
Cardiac Catheter ◽  
Before And After

SummaryBivalirudin, a direct thrombin inhibitor binds specifically and reversibly to both fibrin-bound and unbound thrombin. Bivalirudin is approved for use as an anticoagulant in patients undergoing percutaneous coronary intervention. The OASIS-5 trial presented a significant increase in cardiac catheter thrombosis for the pentasaccharid fondaparinux compared to enoxaparin. Catheter thrombosis has never been reported in any trial using bivalirudin. Our study compared the development of catheter thrombosis for bivalirudin, enoxaparin, and unfractionated heparin in a controlled in-vitro environment. Ten healthy male volunteers were pretreated with aspirin 500 mg 2 hours before venesection of 50 ml of blood. The seven groups of anticoagulant combinations tested were:UFH, UFH + eptifibatide, enoxaparin, enoxaparin + eptifibatide, bivalirudin bolus, bivalirudin + eptifibatide, bivalirudin bolus + continuous infusion. The blood/anticoagulant mix continuously circulated through a cardiac guiding catheter for 60 minutes or until the catheter became blocked with thrombus. Thrombus development was assessed by weighing each catheter before and after the procedure. Electron microscopy was used to quantify the degree of erythrocyte, platelet and fibrin deposition. Following anticoagulation with bolus dose bivalirudin, the catheter was invariably occluded with thrombus after 33 minutes of circulation. However, a continuous infusion of Bivalirudin prevented the development of occlusive catheter thrombosis. In the bolus bivalirudin group the mean thrombus weight was significantly greater than in all other groups (p-value < 0.01 in all analyses). Bivalirudin given as a bolus was not sufficient to prevent cardiac catheter thrombosis in our in-vitro study. However, a continuous infusion of bivalirudin had similar anti-thrombotic efficacy compared to other treatment strategies.

In vitro Study into the Influence of X-Ray Beam Angulation on the Detection if Artificial Caries Defects on Bitewing Radiographs

1989 ◽  
Vol 23 (5) ◽  
pp. 334-341 ◽  
Author(s):  
P.F. van der Stelt ◽  
U.E. Ruttiman ◽  
R.L. Webber ◽  
P. Heemstra
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
X Ray

Fabrication and in Vitro Evaluation of Calcium Phosphate Combined with Chitosan Fibers for Scaffold Structures

2009 ◽  
Vol 24 (1_suppl) ◽  
pp. 113-124 ◽  
Author(s):  
Qin Lian ◽  
Dichen Li ◽  
Zhongmin Jin ◽  
Jue Wang ◽  
Aimin Li ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Calcium Phosphate ◽  
In Vitro Study ◽  
Cement Composites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chitosan Fiber ◽  
In Vitro Performance ◽  
Rapid Tool

A rapid prototyping and rapid tool technique-based method was developed to fabricate chitosan fiber calcium phosphate cement composites (CF/CPC) for bone tissue engineering scaffold applications. The products were characterized and the in vitro performance with canine bone marrow stem cells (BMCs) on CF/CPC scaffold with controlled fiber structures evaluated. The X-ray diffraction analysis showed that about 91% of the inorganic part of the CF/CPC scaffold was hydroxyapatite (HA) and the variation in CF had little effect on the percentage of HA content. The results from in vitro study demonstrated that the interconnected macropores rapidly formed inside the CF/CPC scaffolds and that the patterns were related to the fiber structures used. The differences in the fiber structures altered the morphology of the BMCs without affecting the proliferation of the BMCs.

scholarly journals MicroCT X-ray comparison of aligner gap and thickness of six brands of aligners: an in-vitro study

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Luca Lombardo ◽  
Mario Palone ◽  
Mattia Longo ◽  
Niki Arveda ◽  
Michele Nacucchi ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
X Ray

scholarly journals Efficacy of silver and gold nanoparticles obtained from vermiwash: In vitro study on antimicrobial and antidiabetic activities

2021 ◽  
Vol 13 (4) ◽  
pp. 1317-1325
Author(s):  
Latha Rathinam ◽  
S. P. Sevarkodiyone ◽  
J. Pandiarajan
Keyword(s):  
Gold Nanoparticles ◽  
In Vitro Study ◽  
Xrd Analysis ◽  
Antidiabetic Activity ◽  
Assay Method ◽  
Sem Images ◽  
X Ray ◽  
Silver And Gold Nanoparticles ◽  
Vitro Effect

Emerging nanobiotechnology has provided innovative techniques to synthesize nanoparticles through biological methods to explore the potentialities of biological sources like phytoextracts, microbes, animal secretions and excretion. This research studies the potential of vermiwash to synthesize the silver and gold nanoparticles and evaluate its in vitro effect of antimicrobial   and antidiabetic activities. The characterization of the nanoparticles was analyzed through various techniques. Ultraviolet (UV)-Visible spectroscopy showed the maximum absorption spectrum at 413 nm for silver and 541 nm for gold nanoparticles. Fourier transform infrared spectroscopy (FTIR) revealed the reducing agent involved in nanoparticles synthesis. Scanning electron microscope (SEM) images revealed the size of the silver and gold nanoparticles as 24 nm and 50 nm, respectively. Energy dispersive X-ray (EDAX) analysis revealed the elemental composition of the synthesized nanoparticles. X-ray diffraction (XRD) analysis confirmed the crystalline nature of the nanoparticles that displayed the preferential orientation of the crystals toward the (111) plane.  Antimicrobial activity was assessed using the resazurin assay method.  A minimum inhibitory concentration (MIC) of less than 7.8 µg was observed in Staphylococcus aureus and Klebsiella pneumoniae. In the antifungal activity, MIC at 250 µg was noted in Mucor sp. and Candida albicans. Antidiabetic activity was assessed by α-amylase and α-glucosidase inhibitory assay. IC50 of α-amylase and α-glucosidase activity of the silver nanoparticles was noted as 218 and 221 µg/mL, respectively. IC 50 value for the enzymatic assay dose-dependently confirmed the effect. Conclusively biosynthesized nanoparticles from vermiwash showed potential efficiency of antibacterial, antifungal and antidiabetic activities.

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