Abstract
To reduce variability of Cobb angle measurement for scoliosis assessment, a computerized method was developed. This method automatically measured the Cobb angle on spinal posteroanterior radiographs after the brightness and the contrast of the image were adjusted, and the top and bottom of the vertebrae were selected. The automated process started with the edge detection of the vertebra by Canny edge detector. After that, the fuzzy Hough transform was used to find line structures in the vertebral edge images. The lines that fitted to the endplates of vertebrae were identified by selecting peaks in Hough space under the vertebral shape constraints. The Cobb angle was then calculated according to the directions of these lines. A total of 76 radiographs were respectively analyzed by an experienced surgeon using the manual measurement method and by two examiners using the proposed method twice. Intraclass correlation coefficients (ICC) showed high agreement between automatic and manual measurements (ICCs > 0.95). The mean absolute differences between automatic and manual measurements were less than 5°. In the interobserver analyses, ICCs were higher than 0.95, and mean absolute differences were less than 5°. In the intraobserver analyses, ICCs were 0.985 and 0.978, respectively, for each examiner, and mean absolute differences were less than 3°. These results demonstrated the validity and reliability of the proposed method.
References
Yawn BP, Yawn RA, Hodge D, Kurland M, Shaughnessy WJ, Ilstrup D, Jacobsen SJ: A population-based study of school scoliosis screening. JAMA 282:1427–1432, 1999
Rogala EJ, Drummond DS, Gurr J: Scoliosis: incidence and natural history. A prospective epidemiological study. J Bone Joint Surg Am 60:173–176, 1978
Lonstein JE: Adolescent idiopathic scoliosis. Lancet 344:1407–1412, 1994
Cobb JR: Outline for the study of scoliosis. Am Acad Orthop Surg Inst Course Lect 5:261–275, 1948
Morrissy RT, Goldsmith GS, Hall EC, Kehl D, Cowie GH: Measurement of the Cobb angle on radiographs of patients who have scoliosis. Evaluation of intrinsic error. J Bone Joint Surg Am 72:320–327, 1990
Pruijs JEH, Hageman MAPE, Keessen W, Meer R, Wieringen JC: Variation in Cobb angle measurements in scoliosis. Skelet Radiol 23:517–520, 1994
Greiner KA: Adolescent idiopathic scoliosis: radiologic decision-making. Am Fam Phys 65:1817–1822, 2002
Allen S, Parent E, Khorasani M, Hill DL, Lou E, Raso JV: Validity and reliability of active shape models for the estimation of Cobb angle in patients with adolescent idiopathic scoliosis. J Digit Imaging 0:1–11, 2007
Chockalingam N, Dangerfield PH, Giakas G, Cochrane T, Dorgan JC: Computer-assisted Cobb measurement of scoliosis. Eur Spine J 11:353–357, 2002
Xu Z, Pan J, Zhang S: A novel automatic framework for scoliosis x-ray image retrieval. IJCNN 2007, Oriando, Florida, USA, pp 2482–2485
Han JH, Koczy LT, Poston T: Fuzzy Hough transform. Pattern Recogn Lett 15:649–658, 1994
Lenke LG, Betz RR, Harms J, Bridwell KH, Clements DH, Lowe TG, Blanke K: Adolescent idiopathic scoliosis: a new classification to determine extent of spinal arthrodesis. J Bone Joint Surg AM 83:1169–1181, 2001
Perona P, Malik J: Scale-space and edge detection using anisotropic diffusion. IEEE Trans Pattern Anal Mach Intell 12:629–639, 1990
Canny J: A computational approach to edge detection. IEEE Trans Pattern Anal Mach Intell 8:679–714, 1986
Hough PVC: Method and means for recognizing complex patterns. U.S. Patent 3069654, 1962
Duda RO, Hart PE: Use of the Hough transform to detect lines and curves in pictures. Commun Ass Comput Mach 15:11–15, 1972
Shrout P, Fleiss J: Intraclass correlations: uses in assessing rater reliability. Psychol Bull 68:420–428, 1979
Currier DP: Elements of research in physical therapy, Baltimore: Williams and Wilkins, 1990
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This work was supported by Edmonton Orthopedic Research Society.
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Zhang, J., Lou, E., Le, L.H. et al. Automatic Cobb Measurement of Scoliosis Based on Fuzzy Hough Transform with Vertebral Shape Prior. J Digit Imaging 22, 463–472 (2009). https://doi.org/10.1007/s10278-008-9127-y
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DOI: https://doi.org/10.1007/s10278-008-9127-y