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. 2009 Dec;31(10):1337-42.
doi: 10.1016/j.medengphy.2009.08.011. Epub 2009 Oct 12.

Reliability, validity, and precision of an active stereophotogrammetry system for three-dimensional evaluation of the human torso

Scott M Paul  1 , Andrew P Chamberlin, Charles Hatt, Amritha V Nayak, Jerome V Danoff
Affiliations

Reliability, validity, and precision of an active stereophotogrammetry system for three-dimensional evaluation of the human torso

Scott M Paul et al. Med Eng Phys. 2009 Dec.

Abstract

To determine the reliability, stability, validity and precision of a stereophotogrammetry (SP) system for use in quantifying the complex three-dimensional structure of the human torso, we performed assessments of the system using images of geometric solids and a human-form mannequin. Analysis of geometric solids revealed excellent intra- and interrater reliability of the system for linear, surface area and volume measurements (r>0.99, P<0.001). Overall, no significant difference was found between SP and manual measurements (F=4.23, P>0.06). The system exhibited excellent stability in images of the mannequin over time (r>0.99). The limit of precision (error>5%) of the system to detect objects on the surface of the mannequin was estimated at an object size of 23.5cm(2) for surface area and 32mL for volume. These results demonstrate the capability of SP of the torso to be used as a reliable, stable and valid measure of torso morphology to be applied as a clinical outcome tool in studies of bony and soft tissue pathologies such as scoliosis, rib deformities, obesity or edema.

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Conflict of interest statement

Conflict(s) of interest: None

Figures

Figure 1
Figure 1
Series of sample images of a 4″ sphere taken from one of the imaging pods. The two black and white images (A and B) show the speckle pattern applied by the projector. The color image (C) provides surface texture which is applied to the 3D model. The wire frame model (D) is a created by compiling the images from all four pods, a total of eight images (plus four color images to apply the surface texture).
Figure 2
Figure 2
Diagrams of the camera pod arrangements for the two capture modes: 180 (A) and 360 (B) degrees.
Figure 3
Figure 3
System precision as represented by percent error in SP measurement of half-sphere size: Percent error in the SP calculated surface area (A) and volume (B) of different sized half-spheres imaged on a flat surface and on a human-form mannequin compared to the manual measurements.
Figure 4
Figure 4
The stability of the system image capture was tested by taking repeated images of the human-form mannequin over time in both 180 (A) and 360 (B) degree modes. Images were obtained every 20 minutes for 5 and 2/3 hours to obtain a total of 17 images. The four measurements that were taken on each image were: The caliper distance between nipples (NC), the surface distance between nipples (NSD), the caliper distance between acromia (AC) and the surface distance between acromia (ASD).
See this image and copyright information in PMC

References

    1. Herron R. A biomedical perspective on stereographic anthropometry. Biomedical Sciences Instrumentation. 1969;1969:53–56.
    1. Lee J-Y, Choi J-W. Validity and Reliability of an Alginate Method to Measure Body Surface Area. Journal of Physiological Anthropology. 2006;25(3):247–255. - PubMed
    1. Aldridge K, Boyadjiev SA, Capone GT, DeLeon VB, Richtsmeier JT. Precision and error of three-dimensional phenotypic measures acquired from 3dMD photogrammetric images. American Journal of Medical Genetics Part A. 2005;138A(3):247–253. - PMC - PubMed
    1. Weinberg SM, Naidoo S, Govier DP, Martin RA, Kane AA, Marazita M. Anthropometric Precision and Accuracy of Digital Three-Dimensional Photogrammetry: Comparing the Genex and 3dMD Imaging Systems with One Another and with Direct Anthropometry. Journal of Craniofacial Surgery. 2006 May;17(3):477–483. - PubMed
    1. Ghoddousi H, Edler R, Haers P, Wertheim D, Greenhill D. Comparison of three methods of facial measurement. International Journal of Oral and Maxillofacial Surgery. 2007;36(3):250–258. - PubMed