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X-ray Vision: Diagnostic X-rays and CT Scans
Published in Suzanne Amador Kane, Boris A. Gelman, Introduction to Physics in Modern Medicine, 2020
Suzanne Amador Kane, Boris A. Gelman
Dual energy x-ray absorptiometry (DEXA or DXA) is the present “gold standard” for osteoporosis screening. DEXA uses collimated x-rays from an x-ray tube source and a scintillation detector positioned so it intercepts x-rays transmitted through the body section of interest, such as the hip, spine, or wrist. At each position, a reading yields the sum of transmitted x-ray intensity (and hence x-ray absorption) along one line through the body. This includes the effect of x-ray absorption from both bone and the surrounding soft tissues; however, the absorption due to soft tissue can be compensated for by comparing different beam paths that do (path A) and do not (path B) include bone.
Survey of Osteoporotic Bone Detection Using Texture Analysis
Published in Durgesh Kumar Mishra, Nilanjan Dey, Bharat Singh Deora, Amit Joshi, ICT for Competitive Strategies, 2020
H. B. Pallavi, Shanmuga rathinam ganesa rathinam
Osteoporosis is diagnosed by measuring the density of the bone using a Dual-Energy X-ray Absorptiometry (DEXA) scan. This provides the density of the bone under consideration and can also be used to assess the body composition in terms of lean muscle and fat. The dual energy X-ray absorptiometry scan makes use of two low energy X-ray beams separating the soft tissue from the bone. These scans are more accurate in identifying osteoporotic bones as it can detect even a small change in bone density.
Physical profiles of elite, sub-elite, regional and age-group netballers
Published in Journal of Sports Sciences, 2019
Marni J. Simpson, David G. Jenkins, Michael D. Leveritt, Vincent G. Kelly
Height and body mass were measured using a stadiometer (Seca 213, Vogel & Halke, Hamburg, Germany) and weighing scales (Seca 762, Vogel & Halke, Hamburg, Germany). Body composition (fat mass, lean mass and body fat percentage) and bone density was measured using a fan-beam dual-energy X-ray absorbtiometry (DEXA) scanner (Hologic QDR Discovery, MA, USA) for elite and sub-elite players only. The standard protocol was used for a Whole Body DXA scan and all scans were performed in the morning, with the athlete ensuring correct positioning (head straight, space between arms and torso, and feet together). Athletes were also encouraged before each scan to maintain a normal hydration status. Speed and acceleration were assessed using a 20m sprint test; all players performed three maximum sprints through dual beam timing gates (Fusion Sport Smart Speed, Brisbane, Australia) positioned at 0 m, 5 m, 10 m and 20 m. Timing gates were positioned at approximate hip height and players started with a foot 30cm behind the first timing gate. A minimum of 120 seconds rest separated each sprint and the fastest time was recorded for later analysis (Taylor, Bonetti, & Tanner, 2013).
A new biosensor for osteoporosis detection
Published in Preparative Biochemistry & Biotechnology, 2019
Sevilay Inal Kabala, Hulya Yagar, Hakkı Mevlut Ozcan
Bone mineral density (BMD) measurement and Dual-Energy-X-ray (DEXA) are commonly used in the diagnosis of osteoporosis.[6] However, these techniques have some limitations. The costs of technologies and the monitoring of bone loss require at least 2–3 years. This reveals the importance and the necessity for instantaneous measurement of bone metabolism.[7] The state of the bone cycle is monitored by measuring the biochemical markers. ELISA, RIA, and HPLC are the most widely used methods to detect biochemical markers of bone turnover.[8] Despite high accuracy, these techniques are both costly and require large bulky devices. Also, they are time-consuming and technically trained personnel are needed. Recently, the advances in biosensor technology may allow the evaluation of the metabolic status of the bone. Since biosensors are the measurement systems, which can easily analyze the compounds with a lower cost when compared to other methods, low-cost, fast, reliable, and high-precision biosensors may be developed to use in the osteoporosis diagnosis.
A Survey on Osteoporosis Detection Methods with a Focus on X-ray and DEXA Images
Published in IETE Journal of Research, 2022
S.M. Nazia Fathima, R. Tamilselvi, M. Parisa Beham
This survey mainly contributes to some of the early methods for bone density measurement and work done so far for the determination of bone density from X-ray and DEXA images. Though, DEXA is a simple, quick, non-invasive procedure for the diagnosis of osteoporosis that uses a very small amount of radiation and measures BMD at both the hip and spine. It has some limitations. A critical shortcoming of DEXA is inconsistency in BMD measurements with different DEXA machines from different manufacturers as different image analysis algorithms are used. The differences are due to different edge detection methods, scanner design and calibration. BMD measurements for the same patients made on different DEXA scanners of the same or different manufacturers are different. DEXA scanners generate two-dimensional images of complex three-dimensional structures. An evident drawback of DEXA is that a larger bone will convey superior strength that may have the same bone density as a smaller bone. Paediatric BMD measurements present several technical problems such as the edge detection algorithms designed for adult structure may not be suitable for paediatric cases. Hologic provided alternative algorithms for low bone density studies. DEXA needs ethnic-specific reference data. There are various factors that influences the effective diagnosis of osteoporosis by DEXA. Reference is taken from the right populations. As it varies in accordance with the genetic makeup, the environmental setup, personal habits, lifestyle, etc. of that particular geographical area/race/sex. Most of the reference data are Caucasian races; there is a lacking of suitable reference data for other ethnic groups. In DEXA imaging, there is manual intrusion, that may lead to several misinterpretations if ROIs is not extracted accurately.