J Bone Metab.  2014 Feb;21(1):2-7.

Quality Control of DXA System and Precision Test of Radio-technologists

• Kim HS
• Yang SO

Abstract

The image quality management of bone mineral density (BMD) is the responsibility and duty of radio-technologists who carry out examinations. However, inaccurate conclusions due to the lack of understanding and ignorance regarding the methodology of image quality management can be a fatal error to patients. The accuracy and precision of BMD measurement must be maintained at the highest level so that actual biological changes can be detected with even slight changes in BMD. Accuracy and precision should be continuously preserved for image quality of machines. Those factors will contribute to ensure the reliability of BMD examination. The enforcement of proper quality control of radiologists performing BMD inspections which brings about the durability extensions of equipment and accurate results of calculations will help the assurance of reliable inspections.

Keyword

Bone density; Densitometry; Dual-energy X-ray absorptiometry; Precision; Quality control

MeSH Terms

Absorptiometry, Photon
Bone Density
Densitometry
Humans
Quality Control*

Figure

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  Fig. 1 General phantoms and scan images. (A) The European Spine Phantom (ESP; QRM GmbH Dorfstrasse 4. 91096, Möhrendorf, Germany). (B) ESP scan image. (C) Bio-imaging bone fide spine phantom (BFP; Bio-Imaging Technologies Inc., Newtown, PA, USA). (D) BFP scan image.

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  Fig. 2 Precision test method.

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  Fig. 3 Calculation of least significant change (LSC) at 95% confidence level (in case of device error: 1%, operator error: 1%).

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  Fig. 4 Variation of precision error according to confidence level.

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