06 List Of Figures

LIST OF FIGURES

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List of Figures Chapter 1 1.2.1. The angular momentum of a spin- 12 nucleus ....................................................3 r 1.2.2. Spin- 12 nuclei in a static magnetic field, B0 .....................................................4 1.2.3. The net magnetization ........................................................................................8 1.4.1. The free-induction decay (FID) .......................................................................11 1.5.1. Fourier pairs commonly used in NMR ............................................................15 1.5.2. The FID and the Fourier transform (FT) of the FID ........................................16 1.5.3. Sinc and rectangular wave Fourier pair ...........................................................16 1.6.1.1. Inversion of spins upon application of a 180° pulse ........................................18 1.6.1.2. Inversion-recovery (IR) pulse sequence ..........................................................19 1.6.1.3. Inversion-recovery (IR) curve..........................................................................20 1.6.2.1. Hahn spin echo (SE) pulse sequence ...............................................................22 1.6.2.2. Spin behavior during Hahn spin echo pulse sequence .....................................23 Chapter 2 2.1.1. 1-3-3-1 binomial pulse .....................................................................................26 2.1.2. Illustration of a 1-3-3-1 chemical-shift-selective binomial pulse sequence on the net magnetization of water and fat .............................................................27 2.2.1. Stimulated-echo (STE) pulse sequence ...........................................................30 2.3.1.1. Relative field strength as a function of spatial position ...................................31 2.3.3.1. Sinc and rectangular wave Fourier pair ...........................................................35 2.3.4.1. Phase-encoding gradient ..................................................................................36 2.3.5.1. Conventional two-dimensional Fourier imaging k-space raster ......................38 2.3.5.2. Gradient-recalled echo (GRE) pulse sequence ................................................39 2.3.5.3. Spin-echo echo-planar imaging (SE-EPI) pulse sequence...............................41 2.3.5.4. Saw tooth k-space trajectory for echo-planar imaging ....................................41 2.4.2.1. Stejskal-Tanner pulsed-field gradient spin-echo (PFGSE) pulse sequence .....48 Chapter 3 3.1. Plot of spectroscopically determined ∆pO2 as a function of time postirradiation with a single large dose (1000 cGy) of 6 MeV electrons ...............62 3.2. Plot of ∆pO2 determined using the weighted-average of the T1-maps as a function of time post irradiation with a single large dose (1000 cGy of 6 MeV electrons) ..........................................................................................................63 3.3. pO2 maps of typical tumors during the time course of the radiation therapy study .................................................................................................................64

LIST OF FIGURES

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Chapter 4 4.1. Examples of oxygen tension maps in a RIF-1 tumor as a function of breathing gas ....................................................................................................................82 4.2. Example of a histological slide used to determine necrotic regions for RIF-1 tumors ..............................................................................................................84 4.3. Schematic representation of a typical D(t) versus t½ curve for a RIF-1 tumor showing the four maps used in the analysis (out of the twenty acquired) .......85 4.4. Scatter plots for the shortest and longest diffusion times showing the correlation between D(t) for air breathing and D(t) for carbogen breathing for a single RIF-1 tumor ........................................................................................86 4.5. Scatter plots for air and carbogen breathing showing the correlation between D(t) and pO2 for the longest diffusion time for a single RIF-1 tumor .............87 Chapter 5 5.1.4.1. 5.1.4.2. 5.1.5.1. 5.1.5.2. 5.1.5.3. 5.1.5.4. 5.1.5.5.

Inversion-recovery spin-echo pulse sequence with diffusion gradients ........110 Pulsed-field-gradient spin-echo (PFGSE) pulse sequence ............................111 Inversion-recovery curves at different gradient values ..................................114 Inversion-recovery curves at different echo times .........................................115 Diffusion attenuation curve for yeast-cell suspension acquired using PFGSE pulse sequence in Fig. 5.1.4.2 ........................................................................118 Calculated M0a and M0b from water in yeast-cell suspensions plotted as a function of b-value .........................................................................................119 Normalized plot of the calculated fits using the two different methods ........120

Chapter 6 6.1. 6.2. 6.3. 6.4. 6.5. 6.6. 6.7. 6.8. 6.9. 6.10.

Loading protocol for rabbit Achilles tendon ..................................................133 Load dependence of ADC || and ADC⊥ for applied loads of 0.4, 5, 10, and 0.4 N...............................................................................................................136 Load dependence of ADC⊥ for applied loads of 0.4, 5, 10, and 0.4 N at 10, 30, and 60 ms diffusion times ........................................................................137 The diffusion-time dependence of water ADC⊥ and ADC || .........................138 Response of a fresh tendon to static 5-N loading ..........................................139 Response of a fresh tendon to static 5-N loading and unloading ...................140 Average tendon response curve to static 5-N loading and unloading (n = 8) 140 Comparison of diffusional anisotropy for tendons stored frozen in phosphate buffered saline and freshly harvested tendons ...............................................141 Stress-strain curve for an Achilles tendon using loads up to 10 N ................143 Photograph showing the extrusion of bulk water from a rabbit Achilles tendon (stored in phosphate-buffered saline) under a 10-N load...............................144