- New imaging methods of Achilles tendon based on magnetic resonance for clinical applications
- Optical measurement methods for nanoelectronics
- New magnetic resonance imaging based diagnostic methods of musculoskeletal system
- Comparison of coherence and phase synchronization on sleep electroencephalogram
- Model based interpretation of the nondipolarity in integral surface potential maps accidentally occurring in arrhythmia patients
Result 1: New imaging methods of Achilles tendon based on magnetic resonance for clinical applications
Projects: Project
VEGA 2/0090/11 and ŠPVV
no. 2003SP200280203. (Institute of measurement science SAS).
Authors: V. Juráš, L.
Valkovič, P. Szomolányi, I. Frollo
New methods of lower leg imaging have been investigated by magnetic resonance imaging (MRI). Novel imaging methods have been developed for visualization of the ankle joint and Achilles tendon disease. Based on the known biochemical analysis which validated the increase of proteoglycan content in degenerative tendon disease, we suggested new method for sodium MRI of Achilles tendon. This method is able to reveal the disease in early stages. Method was validated on 20 volunteers and 8 patients with Achilles tendinopathy. This approach offers the link between biochemical knowledge and noninvasive diagnostic method.
Thorough investigation has been performed in measuring of relaxation constants in Achilles tendon. The calculation of those is quite complicated due to their shortness and multi-component nature. Using the novel 3D-UTE sequence (three-dimensional sequence with ultra-short echo time) we have validated clinical feasibility of relaxation constants on 10 volunteers and 5 patients. It was shown; the relaxation constants can be used for diagnosis of degenerative disorders of collagen fibers in Achilles tendon.
These new methods allow clinicians to reveal degenerative processes in Achilles tendon in early stages.
Co-operating institution:
Univ.-Prof. Dr. Siegfried Trattnig, MR Center, Highfield MR, Department of
Radiology, Medical University of Vienna, Austria.
Fig. 1.A: A morphological image of the ankle of 46-years old patient with the pain in Achilles tendon. Besides the moderate swelling, there is not possible to identify a disorder. B: increased relaxation times suggest the changes in collagen matrix. C: using the sodium imaging, it was possible to non-invasively detect the proteoglycan content typical for tendinopathy.
Publications:
-
JURÁŠ,
Vladimír - ZBÝŇ, Š. - PRESSL, Ch. - VALKOVIČ, Ladislav - SZOMOLÁNYI,
Pavol - FROLLO, Ivan - TRATTNIG, S.
Regional variations of T2* in healthy and pathologic achilles tendon in
vivo at 7 Tesla: Preliminary results. In
Magnetic Resonance in Medicine, 2012, vol. 68, p. 1607-1613. ISSN
0740-3194. (2.964-IF2011)
-
JURÁŠ,
Vladimír - ZBÝŇ, Š. - PRESSL, CH. - DOMAYER, S. - HOFSTAETTER, J. -
MAYERHOEFER, M. - WINDHAGER, R. - TRATTNIG, S. Sodium MR imaging of achilles
tendinopathy at 7 T: Preliminary results. In Radiology, 2012, vol. 262,
no. 1, p. 199-205. ISSN 0033-8419. (5.726-IF2011)
-
JURAS,
V., WELSCH, G., BAER, P., KRONNERWETTER, C., FUJITA, H., TRATTNIG, S.:
Comparison of 3 T and 7 T MRI clinical sequences for ankle imaging. European Journal of Radiology, vol 81,
2012, pp. 1846-1850. (2.606-IF2011)
-
JURÁŠ,
Vladimír - APPRICH, S. - PRESSL, C. - ZBYN, S. - SZOMOLANYI, P. -
DOMAYER, S. - FROLLO, Ivan - TRATTNIG, S. Multiparametric MRI assessment
of cadaver achilles tendon at 7T. In Proceedings of the International
Society for Magnetic Resonance in Medicine (ISMRM 2012) : 20th Annual Meeting
& Exhibition. Editors J.G. Pipe, G.E. Gold et al. - Berkeley, CA, USA :
ISMRM, 2012. ISSN 1545-4428, p. 3317. CD-ROM.
-
JURÁŠ, Vladimír -
PRESSL, C. - NOEBAUER-HUHMANN, I.M. - ZBYN, S. - SZOMOLANYI, P. - DOMAYER, S. -
FROLLO, Ivan - TRATTNIG, S. Sodium MR imaging as a marker for achilles
tendinopathy. In Proceedings of the International Society for
Magnetic Resonance in Medicine (ISMRM 2012) : 20th Annual Meeting &
Exhibition. Editors J.G. Pipe, G.E. Gold et al. - Berkeley, CA, USA :
ISMRM, 2012. ISSN 1545-4428, p. 1461. CD-ROM.
Result 2: Optical measurement methods for nanoelectronics
Projects: -
Author: M. Hain
Long-standing scientific cooperation with the Japanese institute „Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan" was in 2012 focused on the development of optical measuring methods applicable in research and electronic industries in the field of nanoelectronics. Cooperation is covered by a written agreement Memorandum of Understanding of directors of partner institutions, which was in 2012 with the agreement of both parties extended for another five years. A new method of measuring the scattering of optical radiation incident on a surface of the test material was jointly elaborated. The measurement is carried out using the specialized optics, digital CCD camera and computer with the developed measuring software.The method was experimentally verified and the experimental apparatus Scatterometer was developed for the fast measurement of distribution function of the reflected light. The results were published and the equipment was in 2012 protected by a patent on a worldwide basis.
Foreign partner: Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan.
.
Fig.1. Scatterometer for fast and accurate measurement of distribution function of the reflected light (left) and user interface of the developed measuring software (right).
Publications:
- KAWATE, E. - HAIN, Miroslav. New scatterometer
for spatial distribution measurements of light scattering from materials. In Measurement Science Review, 2012, vol.
12, no. 2, p. 56-61. ISSN 1335-8871. (0.418-IF2011; WOS, Scopus, Copernicus
International)
-
KAWATE, Etsuo - HAIN, Miroslav. Optical Characteristic
Measurement Device. Patent č. WO 2012/121323 A1. Dátum nadobudnutia účinkov
patentu: 13.09.2012. (č. prihlášky PCT/JP2012/055945, 08.03.2012). Majiteľ:
National Institute of Advanced Industrial Science and Technology, Tokyo, Japan;
Kawate Etsuo; Hain Miroslav.
Result 3: New magnetic resonance imaging based diagnostic methods of musculoskeletal system
Projects: VEGA 2/0090/11 a ŠPVV
no. 2003SP200280203. (Ústav merania
SAV).
Authors: L. Valkovič, V. Juráš,
P. Szomolányi, I. Frollo, D. Gogola
New diagnostic methods for musculoskeletal system based on the nuclear magnetic resonance (NMR) were developed, experimentally tested and validated in clinical praxis. Special focus was put on imaging methods of these body parts: leg musculature, knee joint, wrist joint and intervertebral disks. In cooperation with the foreign research facility were developed several new imaging and spectroscopic methods usable in clinical praxis. The tests of these new methods were performed on MR systems with different field strengths: 0.18 Tesla, 3.0 Tesla and 7.0 Tesla.
Intensive research was focused on measurements of oxidative muscle metabolism at rest and after exercise. New fast and robust spectroscopic sequence was specially designed for these experiments. In addition, new imaging methods of sodium content in intervertebral disks, knee joint and wrist joint were developed. The newly developed methods were successfully tested on healthy volunteers and patients, validating their possible use in orthopedic clinics and dialectological laboratories. The feasibility of the methods is pronounced especially in patient measurements during follow up after operational treatment.
Co-operating institution: Univ.-Prof. Dr. Siegfried Trattnig, MR Center, Highfield MR,
Department of Radiology, Medical University of Vienna, Austria.
Fig.1. Left: Plot showing high reproducibility of the new method for measurement of muscle metabolism at rest (bright = original method, dark = new method).
Middle: MR image of sodium content in intervertebral disks, the arrow indicates the place of pathology with lower glycosaminoglycan concentration.
Right: MR image of the lumbar spine of the same patient, with possible pathology.
Publications:
- VALKOVIČ,
Ladislav - JURÁŠ, Vladimír - GOGOLA, Daniel - FROLLO, Ivan. The early effect of
alcohol and caffeine on a BOLD signal measured in human hand at low-field MRI.
In Applied Magnetic Resonance, 2012, vol. 42, no. 4, p. 463-471. ISSN
0937-9347. (0.755-IF2011)
- NOEBAUER-HUHMANN,
I.-M., JURAS, V., PFIRRMANN, C.W.A., SZOMOLANYI, P., ZBYN, S.,
MESSNER, A., WIMMER, J., WEBER, M., FRIEDRICH, K.M., STELZENEDER, D., TRATTNIG,
S.: Sodium MR imaging of the lumbar intervertebral disk at 7 T: Correlation
with T2 mapping and modified Pfirrmann score at 3 T - Preliminary results. Radiology,
2012.vol 265, pp. 555-564. (5.726-IF2011)
- ZBÝŇ,
Š. - STELZENEDER, D. - WELSCH, G.H. - NEGRIN, L.L. - JURÁŠ, Vladimír -
MAYERHOEFER, M.E. - SZOMOLÁNYI, Pavol - BOGNER, W. - DOMAYER, S.E.
- WEBER, M. - TRATTNIG, S. Evaluation of
native hyaline cartilage and repair tissue after two cartilage repair surgery
techniques with 23Na MR imaging at 7 T: Initial experience. In Osteoarthritis
and Cartilage, 2012, vol. 20, p. 837-845. ISSN 1063-4584. (3.904-IF2011)
- TRATTNIG,
S. - ZBÝŇ, Š. - SCHMITT, B. - FRIEDRICH, K. - JURÁŠ, Vladimír - SZOMOLÁNYI,
Pavol - BOGNER, W. Advanced MR methods at ultra-high field (7 Tesla) for
clinical musculoskeletal applications. In European Radiology, 2012, vol.
22, p. 2338-2346. ISSN 0938-7994. (3.222-IF2011)
- NÖBAUER-HUHMANN,
I.-M. - PRETTERKLIEBER, M. - ERHART, J. - BÄR, P. - SZOMOLÁNYI, Pavol -
KRONNERWETTER, C. - LANG, S. - FRIEDRICH, K.M. - TRATTNIG, S. Anatomy and
variants of the triangular fibrocartilage complex and its MR appearance at 3
and 7T. In Seminars in Musculoskeletal Radiology, 2012, vol. 16,
no. 2, p. 93-103. ISSN 1089-7860. (0.932-IF2011)
- KRUSCHE-MANDL,
I. - SCHMITT, B. - ZAK, L. - APPRICH, S. - ALDRIAN, S. - JURÁŠ,
Vladimír - FRIEDRICH, K.M. - MARLOVITS, S. - WEBER, M. - TRATTNIG, S. Long-term
results 8 years after autologous osteochondral transplantation: 7 T gagCEST and
sodium magnetic resonance imaging with morphological and clinical correlation.
In Osteoarthritis and Cartilage, 2012, vol. 20, p. 357-363. ISSN
1063-4584. (3.904-IF2011)
- VALKOVIČ,
Ladislav - CHMELIK, M. - KUKUROVA, I.J. - KRŠŠÁK, M. - GRUBER, S. - FROLLO,
Ivan - TRATTNIG, S. - BOGNER, W. Time-resolved phosphorous magnetization
transfer of the human calf muscle at 3T and 7T: A feasibility study. In Proceedings
of the International Society for Magnetic Resonance in Medicine (ISMRM
2012) : 20th Annual Meeting & Exhibition. Editors J.G. Pipe, G.E. Gold
et al. - Berkeley, CA, USA : ISMRM, 2012. ISSN 1545-4428, p. 439. CD-ROM.
- VALKOVIČ,
Ladislav - UKROPCOVA, B. - CHMELIK, M. - BALAZ, M. - TKACOV, M. - BOGNER,
W. - SCHMID, A.I. - FROLLO, Ivan - KLIMES, I. - ZEMKOVA, E. - UKROPEC,
J. - TRATTNIG, S. - KRŠŠÁK, M. Skeletal muscle metabolism measured at rest and
after excercise in obese non-diabetic subjects. In Proceedings of the International
Society for Magnetic Resonance in Medicine (ISMRM 2012) : 20th Annual Meeting
& Exhibition. Editors J.G. Pipe, G.E. Gold et al. - Berkeley, CA, USA :
ISMRM, 2012. ISSN 1545-4428, p. 1436. CD-ROM.
- SHIOMI,
T. - SZOMOLÁNYI, Pavol - JURÁŠ, Vladimír - ZBYN, S. - NISHII, T.
- TRATTNIG, S. Biomechanical MR imaging of the human knee cartilage in vivo. In
Proceedings of the International Society for Magnetic Resonance in
Medicine (ISMRM 2012) : 20th Annual Meeting & Exhibition. Editors J.G.
Pipe, G.E. Gold et al. - Berkeley, CA, USA : ISMRM, 2012. ISSN 1545-4428, p.
1385. CD-ROM.
Result 4: Comparison of coherence and phase synchronization on sleep electroencephalogram
Projects: Bilateral project Slovak Academy of Sciences - Academy of Sciences of the Czech Republic, 2012-2014: Modern methods for evaluation of electrophysiological signals.
Authors: K. Mezeiová, V.
Witkovský, A. Krakovská, M. Chvosteková
Synchronization measures applied to the electroencephalogram (EEG) reflect the level of coordination between different parts of the cerebral cortex. Investigation of these phenomena has been done mostly by the means of coherence. The concept of phase synchronization allows us to separate the effect of the amplitude and phase of the signals. In the first part of the study we compared the two methods to estimate the synchronization of the signals. In the second part we examined the kinds of synchronization occurring during sleep - depending on the strength of the couplings between signals we detect uncorrelated state, the state of phase synchronization or full synchronization. To answer these questions, we have calculated the coherence (Fig. 1), the mean phase synchronization and Pearson’s correlation coefficient of analytic amplitudes in the spectral ranges used in the analysis of EEG. These measures were calculated for 6-channel whole-night EEG recordings from 25 healthy subjects. Evaluation of the measures was made with respect to three aspects - a state of consciousness (waking, sleep with rapid eye movement (REM) and without rapid eye movement (nonREM)), spectrum band and various positions of the electrodes on the head. The results show that the coherence and phase synchronization provide the same statistical differences between sleep stages of human EEG. Regarding the type of EEG synchronization, the high-frequency gamma-band synchronization depends on the state of consciousness, while synchronization in other spectral ranges depends primarily on the positions of the electrodes on the head. The connection between the EEG signals were mainly characterized by a phase synchronization, for most strongly linked parts of the head, full synchronization was present. Full synchronization, which is characterized by high correlation of amplitudes and phases, occurred between the homologous parts of the hemispheres. Weakest synchronization of EEG during sleep was observed between fronto-occipital electrode positions. Considering gamma band, phase synchronization during vigilance and nonREM sleep turns into complete synchronization in REM sleep stages.
Partner: Institute of Computer Science, Academy of Sciences of the Czech Republic
Fig.1. EEG coherence between the head areas during waking hours (black), in nonREM sleep (grey) and in REM sleep (white).
Publication:
- MEZEIOVÁ, Kristína - PALUŠ, M. Comparison of
coherence and phase synchronization of the human sleep electroencephalogram. In
Clinical Neurophysiology, 2012, vol. 123, no. 9, p. 1821-1830. ISSN 1388-2457.
(3.406-IF2011)
Result 5: Model based interpretation of the nondipolarity in integral surface potential maps accidentally occurring in arrhythmia patients
Projects: VEGA 2/0210/10 „Methods and systems for multichannel measurement and evaluation of bioelectric signals of the heart and brain", APVV-0513-10 „Measuring, communication and information systems for monitoring of the cardiovascular risk in hypertension patients". Interacademic cooperation with Hungary, project „Measurement and processing of information for diagnostic brain and heart („Measurement and Information Processing for Diagnostic Imaging of Cardiac and Brain Electrical Fields")
Authors: G. Kozmann, Z. Tarjanyi,
G. Tuboly, V Szathmáry, J. Švehlíková, M. Tyšler
Based on analysis of the nondipolarity index (NDI) in integral surface potential maps for consecutive heart beats it was shown that in some beats the NDI suddenly accidentally increases. It is supposed that this fenomenon could precede later dangerous arrhythmia. Using computer simulations, such changes of myocytes action potentials were modeled in a simplified ventricular model that eventuated in NDI changes identical to those observed in measured patient integral maps. It was shown that extreme NDI values can rise in those heart beats where besides the normal ventricular activation also ectopic activation starting at the outer ventricular walls near apex and advancing towards the inner ventricular walls what is in oposite direction as the normal activation. From the model it could be also deduced that in the vicinity of the ectopic activation, the action potential duration decreases proportionally to the distance from the site of the initial activation.
Foreign partner: Faculty of Information Technologies, Panonia University Veszprém, Hungary
Publications:
-
KOZMANN, G. - TARJÁNYI, Z. - TUBOLY, G. - SZATHMÁRY, V.
- ŠVEHLÍKOVÁ, Jana - TYŠLER, Milan. Model interpretation of
non-dipolar integral body surface QRST maps randomly appearing in arrhythmia
patients. In 8th IFAC Symposium on
Biological and Medical Systems. Editors B. Balazs, A. Steen et al. -
International Federation of Automatic Control, 2012, Vol. 8, Part 1. ISBN
978-3-902823-10-6. CD-ROM.
-
TUBOLY, G. - KOZMANN, G. - TARJÁNYI, Z. - SZATHMÁRY, V.
- ŠVEHLÍKOVÁ, Jana - TYŠLER, Milan. Differences in QRST integral
map variability in healthy subjects and arrhythmia patients. In Variability in
Biomedical Signals : Lecture Notes of the ICB Seminar. Editors R. Maniewski, A.
Liebert, O. Meste, H. Rix. Warsaw, Poland: International Centre of
Biocybernetics, Polish Academy of Sciences, 2012, p. 52 + S10-S11.
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Selected Results