DMFR 50thanniversary: Review article: Local cone beam CT: how did it all start?

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20210276 ◽

2021 ◽

Author(s):

Yoshinori Arai

Keyword(s):

Mathematical Theory ◽

Cone Beam Ct ◽

Review Article ◽

Cone Beam ◽

Dental Practice ◽

Television System ◽

Low Radiation Dose ◽

X Ray ◽

Basic Experiments ◽

Local Cone

The mathematical theory of computed tomography (CT) was proposed by J. Radon in 1917. It was declared that the projection of whole datasets was needed to reconstruct CT images. Therefore, according to J. Radon’s original theory, local cone beam CT (local CBCT) was impossible to achieve. In this paper, I discuss how local CBCT was discovered and developed. Its development required many technical elements, such as a turntable and X-ray television system, for basic experiments such as those on which narrow collimation theory and multifunctional panoramic tomography were based. These experiments endured many failures during development. Now, local CBCT is extremely popular in dental practice because local CBCT has a low radiation dose and high resolution. This paper introduces the technical elements and outlines the important stages during the development of local CBCT in the 1990s.

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A Method to Improve Electron Density Measurement of Cone-Beam CT Using Dual Energy Technique

BioMed Research International ◽

10.1155/2015/858907 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Kuo Men ◽

Jian-Rong Dai ◽

Ming-Hui Li ◽

Xin-Yuan Chen ◽

Ke Zhang ◽

...

Keyword(s):

Electron Density ◽

Cone Beam Ct ◽

Density Measurement ◽

Dual Energy ◽

Cone Beam ◽

Imaging Method ◽

Basis Material ◽

X Ray ◽

Dual Energy Imaging ◽

Set Up

Purpose. To develop a dual energy imaging method to improve the accuracy of electron density measurement with a cone-beam CT (CBCT) device.Materials and Methods. The imaging system is the XVI CBCT system on Elekta Synergy linac. Projection data were acquired with the high and low energy X-ray, respectively, to set up a basis material decomposition model. Virtual phantom simulation and phantoms experiments were carried out for quantitative evaluation of the method. Phantoms were also scanned twice with the high and low energy X-ray, respectively. The data were decomposed into projections of the two basis material coefficients according to the model set up earlier. The two sets of decomposed projections were used to reconstruct CBCT images of the basis material coefficients. Then, the images of electron densities were calculated with these CBCT images.Results. The difference between the calculated and theoretical values was within 2% and the correlation coefficient of them was about 1.0. The dual energy imaging method obtained more accurate electron density values and reduced the beam hardening artifacts obviously.Conclusion. A novel dual energy CBCT imaging method to calculate the electron densities was developed. It can acquire more accurate values and provide a platform potentially for dose calculation.

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Dental cone-beam CT reconstruction from limited-angle view data based on compressed-sensing (CS) theory for fast, low-dose X-ray imaging

Journal of the Korean Physical Society ◽

10.3938/jkps.64.1907 ◽

2014 ◽

Vol 64 (12) ◽

pp. 1907-1911

Author(s):

Uikyu Je ◽

Hyosung Cho ◽

Minsik Lee ◽

Jieun Oh ◽

Yeonok Park ◽

...

Keyword(s):

Compressed Sensing ◽

Low Dose ◽

Cone Beam Ct ◽

Cone Beam ◽

Ct Reconstruction ◽

X Ray ◽

X Ray Imaging ◽

Limited Angle

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X-ray scatter correction algorithm for cone beam CT imaging

Medical Physics ◽

10.1118/1.1711475 ◽

2004 ◽

Vol 31 (5) ◽

pp. 1195-1202 ◽

Cited By ~ 220

Author(s):

Ruola Ning ◽

Xiangyang Tang ◽

David Conover

Keyword(s):

Cone Beam Ct ◽

Scatter Correction ◽

Ct Imaging ◽

Cone Beam ◽

Correction Algorithm ◽

X Ray

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Dimensional accuracy of cone beam CT with varying angulation of the jaw to the X-ray beam

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20180319 ◽

2019 ◽

Vol 48 (4) ◽

pp. 20180319

Author(s):

George K. Koch ◽

Adam Hamilton ◽

Kelly Wang ◽

Laura Herschdorfer ◽

Kyu Ha Lee ◽

...

Keyword(s):

Cone Beam Ct ◽

Dimensional Accuracy ◽

Cone Beam ◽

X Ray

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Patient Knowledge Regarding Radiation Exposure from Orthopaedic Foot and Ankle Imaging

Foot & Ankle Orthopaedics ◽

10.1177/2473011418s00158 ◽

2018 ◽

Vol 3 (3) ◽

pp. 2473011418S0015

Author(s):

Daniel Bohl ◽

Blaine Manning ◽

George Holmes ◽

Simon Lee ◽

Johnny Lin ◽

...

Keyword(s):

Ionizing Radiation ◽

Ct Scan ◽

Radiation Exposure ◽

Cone Beam Ct ◽

Plain Film ◽

Ct Scans ◽

Cone Beam ◽

X Rays ◽

Foot And Ankle ◽

X Ray

Category: Other Introduction/Purpose: Foot and ankle surgeons routinely prescribe diagnostic imaging that exposes patients to potentially harmful ionizing radiation. The purpose of this study is to characterize patients’ knowledge regarding radiation exposure associated with common forms of foot and ankle imaging. Methods: A survey was administered to all new patients prior to their first foot and ankle clinic appointments. Patients were asked to compare the amount of harmful radiation associated with chest x-rays to that associated with various types of foot and ankle imaging. Results were tabulated and compared to actual values of radiation exposure from the published literature. Results: A total of 890 patients were invited to participate, of whom 791 (88.9%) completed the survey. The majority of patients believed that a foot x-ray, an ankle x-ray, a “low dose” CT scan of the foot and ankle (alluding to cone-beam CT), and a traditional CT scan of the foot and ankle all contain similar amounts of harmful ionizing radiation to a chest x-ray (Table 1). This is in contrast to the published literature, which suggests that foot x-rays, ankle x-rays, cone beam CT scans of the foot and ankle, and traditional CT scans of the foot and ankle expose patients to 0.006, 0.006, 0.127, and 0.833 chest x-rays worth of radiation. Conclusion: The results of the present study suggest that patients greatly over-estimate the amount of harmful ionizing radiation associated with plain film and cone-beam CT scans of the foot and ankle. Interestingly, their estimates of radiation associated with traditional CT scans of the foot and ankle were relatively accurate. Results suggest that patients may benefit from increased counseling by surgeons regarding the relatively low risk of radiation exposure associated with plain film and cone-beam CT imaging of the foot and ankle.

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The way we were (and how we got here): fifty years of technology changes in dental and maxillofacial radiology

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20200133 ◽

2020 ◽

pp. 20200133 ◽

Cited By ~ 1

Author(s):

Roberto Molteni

Keyword(s):

Cone Beam Ct ◽

Cone Beam ◽

Maxillofacial Radiology ◽

Technological Changes ◽

X Ray ◽

Technology Changes ◽

The World ◽

History Of ◽

Phosphor Plates ◽

Different Parts

The history of the last 50 years (1970–2020) of technological changes and progresses for equipment and procedures in dental and maxillofacial radiology is related from the insider perspective of an industrial physicist and technologist who has been instrumental at innovating and developing medical equipment in different parts of the world. The onset and improvement of all major categories of dental and maxillofacial radiographic equipment is presented, from the standpoint of their practical acceptance and impact among common dentists and maxillofacial radiologists: X-ray sources and detectors for intraoral radiography, and panoramic systems, both film-based and digital (including photo-stimulated phosphor plates); and cone beam CT.

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