Ultra-high field magnetic resonance diffusion tensor imaging of the hyaline articular cartilage [Elektronische Ressource] / Lucianna Filidoro. Betreuer: Maximilian Reiser

Filidoro, Lucianna

Sujets

• Gesundheit

Informations

• Publié par: ludwig-maximilians-universitat_munchen
• Publié le: 01 janvier 2011
• Nombre de lectures: 22
• Poids de l'ouvrage: 11 Mo

Extrait

Aus dem Josef Lissner Laboratory for Biomedical Imaging
des Instituts für Klinische Radiologie
der Ludwig-Maximilians-Universität München


Direktor: Prof. Dr. med. Dr. h.c. Maximilian F. Reiser, FACR, FRCR



Ultra-high field magnetic resonance diffusion tensor imaging
of the hyaline articular cartilage



Dissertation zum Erwerb des Doktorgrades der Humanbiologie
an der Medizinischen Fakultät der Ludwig-Maximilians-Universität zu München





vorgelegt von
Lucianna Filidoro
aus
Florenz (Italien)

2011








Mit Genehmigung der Medizinischen Fakultät der Universität München





Berichterstatter:
Prof. Dr. med. Dr. h.c. Maximilian F. Reiser, FACR, FRCR

Mitberichterstatter:
Prof. Dr. Karl-Hans Englmeier
Prof. Dr. Peter E. Müller

Mitbetreuung durch die promovierten Mitarbeiter:
Prof. Dr. med. Dr. h.c. Maximilian F. Reiser, FACR, FRCR
Priv.-Doz. Dr. med. Christian Glaser
Priv.-Doz. Dr. rer. nat. Olaf Dietrich
Dr. rer. biol. hum. José Raya

Dekan:
Prof. Dr. med. Dr. h.c. Maximilian F. Reiser, FACR, FRCR



Tag der mündlichen Prüfung:
21.11.2011





Content


1 Introduction ................................................................................................................... 1
2 Articular cartilage .......................................................................................................... 5
2.1 Functional characteristics and composition ....................................................... 5
2.2.1 Morphology ................................................................................................ 7
2.2.2 Chondrocytes .............................................................................................. 9
2.2.3 Collagen ...................................................................................................... 9
2.2.4 Glycans ..................................................................................................... 11
2.2.5 Interstitial water ........................................................................................ 13
2.2.6 Metabolic activities................................................................................... 13
2.3 Ultrastructure ................................................................................................... 14
2.3.1 Tangential zone......................................................................................... 15
2.3.2 Transitional zone ...................................................................................... 15
2.3.3 Radial zone ............................................................................................... 15
2.4 Osteoarthritis .................................................................................................... 16
2.4.1 Epidemiology ........................................................................................... 16
2.4.2 Etiology 16
2.4.3 Pathogenesis ............................................................................................. 17
2.4.4 Symptoms ................................................................................................. 19
2.4.5 Diagnosis .................................................................................................. 19
2.4.6 Early diagnosis ......................................................................................... 19
2.4.7 Therapy ..................................................................................................... 20
3 Magnetic resonance imaging (MRI) of molecular diffusion ....................................... 21
3.1 Introduction ...................................................................................................... 21
3.2 Diffusion-weighted imaging (DWI) ................................................................ 23
3.2.1 Theory of diffusion ................................................................................... 23
3.2.2 Measurement principles ............................................................................ 23
3.2.2 Apparent diffusion coefficient (ADC) ...................................................... 26
3.3 Diffusion tensor imaging (DTI) ....................................................................... 27
3.3.1 Determination of the diffusion tensor ....................................................... 27
3.3.2 Quantitative parameters obtained by DTI ................................................ 28
4 DTI of cartilage at 9.4 Tesla ........................................................................................ 31
4.1 Introduction ...................................................................................................... 31



4.2 Materials & Methods ....................................................................................... 32
4.2.1 Sample preparation ................................................................................... 32
4.2.2 MRI ........................................................................................................... 34
4.3 Results .............................................................................................................. 37
4.4 Discussion and conclusions ............................................................................. 43
5 DTI of cartilage at 17.6 Tesla: feasibility and limitations ........................................... 47
5.1 Introduction ...................................................................................................... 47
5.2 Instrument ........................................................................................................ 47
5.2.1 Main magnet ............................................................................................. 48
5.2.2 Gradient system ........................................................................................ 49
5.2.3 RF coil 50
5.3 Optimization of the DTI protocol .................................................................... 51
5.3.1 DTI in an isotropic phantom ..................................................................... 52
5.3.2 Analysis of temperature influences .......................................................... 54
5.3.3 Analysis of b-matrix ................................................................................. 56
5.3.4 Eddy-current effects 57
5.3.5 Chemical-shift artifacts............................................................................. 57
5.4 Coordinate systems .......................................................................................... 61
5.5 FA versus SNR ................................................................................................ 63
5.6 Discussion and conclusions 64
6 DTI of cartilage at 17.6 T: correlation with histology and scanning electron
microscopy ..................................................................................................................... 67
6.1 Introduction ...................................................................................................... 67
6.2 Materials & Methods ....................................................................................... 68
6.2.1 Sample preparation ................................................................................... 68
6.2.2 MRI ........................................................................................................... 68
6.2.3 Biomechanical testing............................................................................... 72
6.2.3 Scanning electron microscopy (SEM) ...................................................... 74
6.2.4 Histology .................................................................................................. 77
6.3 Results .............................................................................................................. 78
6.3.1 MRI 78
6.3.2 Biomechanical testi80
6.3.3 SEM .......................................................................................................... 81
6.3.4 Histology 83
6.4 Discussion and conclusions ............................................................................. 85
6.4.1 Comparison with previous DTI in articular cartilage ............................... 85
6.4.2 DTI under mechanical loading ................................................................. 87
6.4.3 DTI versus SEM ....................................................................................... 87
6.4.4 DTI versus Histology ............................................................................... 88
6.4.5 Influence of cartilage components on the measured parameters .............. 88
6.4.6 Conclusions .............................................................................................. 90
7 Conclusions and summary ........................................................................................... 91
ii



Zusammenfassung .......................................................................................................... 95
Bibliograph