• Osteoporosis diagnostics using magnetic resonance imaging methods

Osteoporosis diagnostics using magnetic resonance imaging methods

Project: VEGA 2/2040/23

Investigators: I. Strolka, V. Jellúš, I. Frollo (IMS SAS) + A. Accardo, D. Dreossi, F. Vittur, R. Toffanin, G. Candido (Dipartimento di Biochimica, Biofisica e Chimica delle Macromolecole, Universitá degli Studi di Trieste, Trieste, Italy)

In collaboration with the University of Trieste, Italy, selected technical aspects related to the observation of the bone osteoporotic status using the methods of MR imaging were studied. Osteoporosis was defined by the World Health Organisation in 1994 as a "systematic skeletal disorder characterised by low bone mass and micro-architectural deterioration of bone tissuewith a consequent increase in bone fragility and susceptibility to fracture".

Currently clinically applied diagnostic methods are based on the X-ray bone mineral density measurements. Estimated bone mineral density (BMD) parameter is the best known singlepredictor of the osteoporotic fracture, however, according to several studies this parameter does not explain 10-90% of the bone strength variation.

Among imaging methods, method of MR imaging can reach highest resolution. Images in the distal radius region with a resolution 156x156x350 micrometers were obtained where individual trabeculae were clearly visible. A new image segmentation method combining an artificial neural network and Markov random field prior model of the trabecular bone image using the Bayes formula was developed. Computer simulation shown, that this method can be used in the presence of a significant amount of noise. NMR methods very likely will not replace in the near future the X-ray osteodensitometry. There is a strong assumption however that after clinical tests NMR methods could be used as a supplementary examination in order to reliably mark those patients, who due to a high risk of the osteoporotic fracture have to undergo an intensive therapy.

Publications:

• STROLKA, Igor - ACCARDO, A. - DREOSSI, D. - VITTUR, F. - TOFFANIN, R. - FROLLO, Ivan. Segmentation of magnetic resonance microimages of trabecular bone: classifiers and Markov random field model. In Measurement Science Review. ISSN 1335-8871. Vol. 3, 2003, p. 53-56.
• ACCARDO, A. - CANDIDO, G. - JELLÚŠ, Vladimír - TOFFANIN, R. - VITTUR, F. Ex Vivo assessment of trabecular bone structure from three-dimensional projection reconstruction MR micro-images. In IEEE Transactions on Biomedical Engineering. ISSN 0018-9294. Vol. 50, no. 8, 2003, p. 967-977.