Applications of Imaging Technologies in Maxillary Cyst Assessment

2017 ◽  
Vol 68 (5) ◽  
pp. 1130-1136
Author(s):  
Ademir Horia Stana ◽  
Otilia Lavinia Stana (Gag) ◽  
Gheorghe Ciobanu ◽  
Anca Porumb ◽  
Calin Gheorghe Cioban ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Panoramic Radiography ◽  
X Rays ◽  
Radiographic Image ◽  
3D Images ◽  
Maxillary Bone ◽  
X Ray ◽  
Pathologic Lesions ◽  
Maxillary Cyst ◽  
Risk Of Exposure

The use of dental radiographies is nowadays indispensible for the clinician, and the evolution of x-rays provide quality images of the anatomic structures. The indications for a radiographic exam must be based on a clinical examination of the patient. Although the most used radiographies in dentistry are the retroalveolar and the panoramic one, it is considered that the indication for a CBCT scanning should be professional justified and evaluated as a balance between the benefits and the risk of exposure at radiation. The CBCT scans provide good quality images of the anatomic structures, with an accurate delimitation of the pathologic lesions, fact that allows the practitioner to proper evaluate the surrounding structures. CBCT technique uses an x-ray beam shaped like a cone that records 3D images in a single gantry rotation (360 degrees) within 6-20 seconds, with a radiation dose that depends on several factors. The comparison of the radiation dose of the CBCT (11-674 mSv) and the panoramic radiography (2.7�24.3 mSv) demonstrates that the CBCT requires a higher dose of radiation, but the high image quality is competing with the ones obtained with MSCT (280�1,410 mSv). The panoramic radiography uses an x-ray beam that is angled at aproximately 8 degrees, providing the practitioner a 2D radiographic image of the anatomic structures. The disadvantages of the panoramic radiography are the overlapping of the anatomic structures, the distortion and the blurry image. The study is based on the measurements of cystic lesions of the mandibular and maxillary bone that were present on radiographies and CBCT scans of 25 patients. The result of the measurements was that significative differences were found between the panoramic image of the cyst and the reconstructive image that the CBCT.

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.

scholarly journals Spectral Tomography for 3D Element Detection and Mineral Analysis

Minerals ◽  
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.

scholarly journals QUALITY CONTROL X RAYS MAMMOGRAPHY IN THE EFFORT MITIGATION INCREASING NUMBER OF CANCER PATIENTS

2017 ◽  
Vol 17 (1) ◽  
pp. 45
Author(s):  
Rini Safitri ◽  
Evi Yufita
Keyword(s):  
Breast Cancer ◽  
Quality Control ◽  
Early Stage ◽  
Input Voltage ◽  
Test Subject ◽  
X Rays ◽  
Radiographic Image ◽  
X Ray ◽  
Radiation Output

Abstract. Early detection of breast cancer is the first step in prevention that can be done by women, therefore when one is diagnosed with breast cancer, the appropriate treatment can be performed quickly and accurately. Early diagnosis of breast cancer can be a way of mitigation in preventing breast cancer through the use of mammography. Bureau of Radiology as said by The Joint Commission on Accreditation of Hospitals (JHCA) stated that one of the responsibilities of the radiology unit is to control the quality of service which aims to minimize the radiographic image repetition factor; as well as maximizes the quality of radiographic image. Quality control tests are an effort that is needed on the mammography X-ray diagnostics tools. This is done to maintain the quality of expected output. The parameters that are included within the radiation output are the magnitude of current and the voltage of tube that are produced; therefore they remained constant and correspond to the recommended standard. Bureau of Radiological Health, as said by JHCA mentioned that to control the quality of image which will minimize the radiographic image repetition and maximizes the quality of radiographic image. Therefore the radiation output will not be dangerous later. The early stage of the quality control test on the machine was conducted by setting all the filtrations which were placed to capture the x-ray on the x-ray plane tube with minimum value. Then, ionization chamber is placed on the test subject points; right after that the distance between it to the radiation source is noted. The x-ray film is place on a film on the compression table of the patient and the distance between film and the focus point is noted. This is then exposed using a target filter Mo/Mo by setting the current as well as variation the voltage and time. The standard voltage measurements are 20-33kVp. This data is from the observations of time exposure; the output value is then noted. The above procedure is conducted from the minimum voltage to the maximum voltage. The output ray is measured for each voltage. The same procedure is conducted to the target filter Mo/RH. The results obtained are that the greater the input voltage and current will subsequently produce greater doses, therefore the exposure has exceeded the standard limit 0.1 mHy with longer exposure time. The HVL density thickness on the mammography X-ray machine determined the quality of the beam and the doses of x-ray exposure on the mammography machine. The output stability of x-ray beam exposure in the mammography machine mode Mo/Mo still fulfill the standard which is the value of 69% Keywords: Quality Control, Sinar-X, mammography, Mp/Mo, Mo/RH

Interaction of ionizing radiations with matter

2015 ◽  
Author(s):  
Colin J Martin
Keyword(s):  
Radiation Dose ◽  
Scattered Radiation ◽  
Final Section ◽  
Radioactive Decay ◽  
Photoelectric Effect ◽  
X Rays ◽  
X Ray ◽  
Radiation Fields ◽  
Ionizing Radiations ◽  
Radiology Image

Interactions of ionizing radiations with matter are fundamental to the practice of radiation protection. They determine the magnitude and distribution of doses in tissues, the performance of detectors and imaging devices, and the attenuating properties of shielding materials. This chapter describes briefly the processes of radioactive decay and the properties of the various particles emitted, and then goes on to consider the interactions of radiation with matter. Electron interactions with metals result in bremsstrahlung and characteristic X-rays that form the basis of X-ray production. The interaction mechanisms of X-rays with tissue, particularly the photoelectric effect and Compton scattering, are inherent in the process of radiology image formation. Understanding the physics behind X-ray interactions so that scattered radiation can be taken into account is crucial in designing methods for accurately measuring radiation dose parameters. The final section deals with the dose related variables involved in measurement of radiation fields.

IN-VIVO ELEMENTAL ANALYSIS BY PIXE-μ-CT

2007 ◽  
Vol 17 (01n02) ◽  
pp. 41-46 ◽  
Author(s):  
Y. KAWAMURA ◽  
K. ISHII ◽  
H. YAMAZAKI ◽  
S. MATSUYAMA ◽  
Y. KIKUCHI ◽  
...  
Keyword(s):  
High Resolution ◽  
Absorption Edge ◽  
Ion Beam ◽  
Projection Data ◽  
Elemental Distribution ◽  
X Rays ◽  
Ct Reconstruction ◽  
3D Images ◽  
X Ray

We have developed “micron-CT”, using micro-PIXE for in-vivo imaging. This system comprises an X-ray CCD camera (Hamamatsu photonics C8800X9) with high resolution (pixel size: 8×8 μm 2, number of pixels: 1000×1000) and an X-ray-point-source with a spot size of 1.5×1.5 μm 2 which is generated by irradiation of a microbeam on a pure metal target. Thus we can acquire projection data with high resolution. The sample is placed in a small diameter tube and is rotated by a stepping motor. The 3D images were reconstructed from the obtained projection data by using cone-beam CT reconstruction algorithm. X-ray spectra produced by heavy charged particle bombardment, exhibit a much smaller continuous background compared to electron bombardment. Therefore, X-rays produced by ion beam can be used as a monochromatic and low energy X-ray source. The feature is very effective to investigate small insects. Moreover we can get elemental distribution image of object by choosing appropriate characteristic X-rays corresponding to the absorption edge. On the other hand, the conventional X-ray CT, in which continuous X-rays are used, provides images of the electron density in the object. Using this system, we were able to get 3D images of a living ant's head with 6 μm spatial resolution. By using Fe - K -X-rays (6.40 keV) and Co - K -X-rays (6.93 keV), we can investigate the 3D distribution of Mn ( K -absorption edge = 6.54 keV) in an ant's head.

scholarly journals UJI KELAYAKAN PESAWAT SINAR-X TERHADAP PROYEKSI PA (POSTERO-ANTERIOR) DAN LAT (LATERAL) PADA TEKNIK PEMERIKSAAN FOTO THORAX

2017 ◽  
Vol 18 (1) ◽  
pp. 27
Author(s):  
Kadek Miniati ◽  
Gusti Ngurah Sutapa ◽  
I Wayan Balik Sudarsana
Keyword(s):  
Radiation Dose ◽  
X Rays ◽  
Tube Voltage ◽  
Limit Values ◽  
X Ray ◽  
Limit Value ◽  
Irradiation Field ◽  
Interval Distance ◽  
Dosage Guidelines ◽  
Feasibility Test

Research has been conducted to determine feasibility test of the X-ray planePA and LAT projections on chest x-ray techniques. The study using a water phantom object as a substitute for patients with variations in interval distance ofthe  100-180 cm. Measurement of radiation dose X-rays performed five repetitions , measurable doses had be read on the device electrometer. Exposition factors to the PA projection using a tube voltage of 75 kV, current and time of 3,2 mAs, the irradiation field areaof (30 x 30) cm2.For the LAT projection tube voltage of 80 kV, current and time of 6,3 mAs, and the irradiation field area of (20 x 30) cm2. It the study of the radiation dose X-ray plane projection PA and LAT is optimal is below the limit value at the level of dosage guidelines BAPETEN No 08 of 2011. Obtained PA projections are below the value of 0,4 mGy while LAT projection is below the value of 1,5 mGy. The radiation dose X-rays plane using a variation of 100-180 cm distance is still below the dose limit values ??, thus meeting the objectives anssurance quality and quality control.

Characterization of the Theorectical Radiation Dose Enhancement from Nanoparticles

2007 ◽  
Vol 6 (5) ◽  
pp. 395-401 ◽  
Author(s):  
John C. Roeske ◽  
Luis Nuñez ◽  
Mark Hoggarth ◽  
Edwardine Labay ◽  
Ralph R. Weichselbaum
Keyword(s):  
Radiation Dose ◽  
Enhancement Factor ◽  
Low Energy ◽  
External Beam ◽  
X Rays ◽  
Nanoparticle Concentration ◽  
Dose Enhancement ◽  
X Ray ◽  
Delivered Dose

Recently, nanoparticles have been considered as a method of providing radiation dose enhancement in tumors. In order to quantify this affect, a dose enhancement factor (DEF) is defined that represents the ratio of the dose deposited in tumor with nanoparticles, divided by the dose deposited in the tumor without nanoparticles. Materials with atomic numbers (Z) ranging from 25 to 90 are considered in this analysis. In addition, the energy spectrum for a number of external beam x-ray sources and common radionuclides are evaluated. For a nanoparticle concentration of 5 mg/ml, the DEF is < 1.05 for Co-60, Ir-192, Au-198, Cs-137, 6, 18, and 25 MV x-rays for all materials considered. However, relatively large increases in the DEF are observed for 50, 80, 100, and 140 KVp x-rays as well as Pd-103 and I-125. The DEF increases for all sources as Z varies from 25–35. From Z = 40–60, the DEF plateaus or slightly decreases. For higher Z materials (Z>70), the DEF increases and is a maximum for the highest Z materials. High atomic number nanoparticles coupled with low energy external beam x-rays or brachytherapy sources offer the potential of significantly enhancing the delivered dose.

WHY MEASUREMENT OF RADIATION DOSE BY MEDICAL PHYSICIST AND RADIATION ONCOLOGIST BOTH?

2021 ◽  
pp. 219-222
Author(s):  
Rubina Rubina ◽  
Baig M.Q ◽  
Kumar Dev
Keyword(s):  
Radiation Dose ◽  
Gamma Rays ◽  
Biological Effect ◽  
Radiation Energy ◽  
The Body ◽  
X Rays ◽  
Radiation Oncologist ◽  
X Ray ◽  
Γ Rays ◽  
Different Tissues

Many years after the discovery of X-ray's and gamma rays. They have been used empirically in medicine, later on realized that this approach was dangerous mainly in radiotherapy and up to some extent in diagnostic radiology. Thus Means of measuring x-ray/γ-rays had to be found in terms of unit of x-rays quantity dened and accepted. The magnitude of the biological effect desirable in case therapy and undesirable in case of diagnosis. It depends upon how much radiation energy is absorbed by irradiated material. X-ray dosimetry is the measurement of energy absorbed in any material particularly in different tissues of the body.

scholarly journals CBCT's Cone Beam Computed Tomography

2014 ◽  
Vol 1 (1) ◽  
pp. 9
Author(s):  
Sahithya Kailash
Keyword(s):  
Computed Tomography ◽  
Panoramic Radiography ◽  
Cone Beam ◽  
X Rays ◽  
Health Issues ◽  
X Ray ◽  
3 Dimensional ◽  
Area Of Interest ◽  
Multiplanar Imaging ◽  
Dimensional Reconstruction

Dental X- Rays are important for diagnosing and treating patients by helping to detect oral health issues when they can't be detected by visual or physical examination alone. Dental X-Ray take a much closer look and provide valuable information in the area of interest. Though 2 Dimensional X-Ray and Panoramic radiography can predict diagnosis in number of clinical cases, certain situations demand multiplanar imaging, one such technology is CBCT. CBCT is a specialised 3Dimensional Craniofacial imaging in which 3 Dimensional reconstruction is possible. The final reconstructed image produced, reveals multilayer images in 3 orthogonal planes (coronal, sagittal and transverse) This article focuses on CBCT and its applications in various fields of dentistry.

scholarly journals Predicting fringe visibility in dual-phase grating interferometry with polychromatic X-ray sources

2020 ◽  
Vol 28 (6) ◽  
pp. 1055-1067
Author(s):  
Aimin Yan ◽  
Xizeng Wu ◽  
Hong Liu
Keyword(s):  
Radiation Dose ◽  
Numerical Simulations ◽  
Design Optimization ◽  
Phase Modulation ◽  
Dual Phase ◽  
X Rays ◽  
Fringe Visibility ◽  
Phase Grating ◽  
X Ray ◽  
Quantitative Theory

Dual phase grating X-ray interferometry is radiation dose-efficient as compared to common Talbot-Lau grating interferometry. The authors developed a general quantitative theory to predict the fringe visibility in dual-phase grating X-ray interferometry with polychromatic X-ray sources. The derived formulas are applicable to setups with phase gratings of any phase modulation and with either monochromatic or polychromatic X-rays. Numerical simulations are presented to validate the derived formulas. The theory provides useful tools for design optimization of dual-phase grating X-ray interferometers.

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