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_3 very important.ppt
The document discusses the physical principles behind signal generation in magnetic resonance imaging (MRI). It describes how hydrogen protons generate a signal when placed in a strong magnetic field. The protons precess around the field at their Larmor frequency. A radiofrequency pulse excites the protons, which then relax back to equilibrium and emit a magnetic resonance signal that is detected by a receiver coil. The signal decays over time according to the T1 longitudinal relaxation time and T2* transverse relaxation time, which are tissue properties that can provide contrast for MRI.
_3 very important.ppt
- 1. HOME philips PHYSICAL PRINCIPLES Signal Generation Changinghow the world looks at MR
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- 3. HOME philips nuclei, protons andspins signal generation longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2
- 4. HOME philips nuclei, protons andspins signal generation longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2
- 5. HOME philips ATOM proton positive charge neutron no charge elektron negativecharge water atom proton nucleus signal generation nuclei, protons and spins
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- 8. HOME philips electric charge + rotation signal generation nuclei,protons and spins magnetism
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- 10. HOME philips X Y Z signal generation nuclei, protonsand spins summed magnetization
- 11. HOME philips X Y Z signal generation nuclei, protonsand spins summed magnetization
- 12. HOME philips X Y Z signal generation nuclei, protonsand spins summed magnetization
- 13. HOME philips 0,01 Tesla 0 Kelvin= - 274 C o o signal generation nuclei, protons and spins
- 14. HOME philips 20 Celsius o 5 ppm 0,5Tesla 1,5 Tesla 15 ppm signal generation nuclei, protons and spins
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- 27. HOME philips B0 f0 = x B0 f = frequency = constant of isotope B = magnetic field signal generation nuclei, protons and spins
- 28. HOME philips signal generation nuclei, protonsand spins fo (0.5 T) fo (1.5 T) 21.3 MHz 42.6 MHz 63.8 MHz 20.0 MHz 40.1 MHz 60.2 MHz 8.6 MHz 17.2 MHz 25.7 MHz 5.7 MHz 11.3 MHz 17.1 MHz 5.4 MHz 10.7 MHz 16.1 MHz 1 H 19 F 31 P 23 Na 13 C Nucleus o (1.0 T) f
- 29. HOME philips signal generation nuclei, protonsand spins 1 H 19 F 31 P 23 Na 13 C Sensitivity 1 0,83 0,066 0,093 0,016 Nucleus
- 30. HOME philips nuclei, protons andspins signal generation longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2
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- 44. HOME philips X Y Z B0 Mz net magnetisation and 90° pulse signalgeneration exitation
- 45. HOME philips net magnetisation and 90° pulse X Z B0 Y signalgeneration exitation
- 46. HOME philips net magnetisation and 90° pulse X Y Z B0 Y signalgeneration exitation
- 47. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 48. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 49. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 50. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 51. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 52. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 53. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 54. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 55. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 56. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 57. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 58. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 59. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 60. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 61. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 62. HOME philips net magnetisation and 90° pulse X Y Z B0 signalgeneration exitation
- 63. HOME philips net magnetisation and 90° pulse X Y Z B0 M signalgeneration exitation
- 64. HOME philips net magnetisation and 90° pulse X Y Z B0 Mxy signalgeneration exitation
- 65. HOME philips nuclei, protons andspins longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2 signal generation
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- 97. HOME philips nuclei, protons andspins longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2 signal generation
- 98. HOME philips longitudinal relaxation T1 Spin- lattice relaxation signal generation
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- 106. HOME philips time Mz T1 definition T1: the timethat a tissue needs to regain 63% of its original magnetisation 63% signal generation longitudinal relaxation T1
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- 114. HOME philips nuclei, protons andspins longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2 signal generation
- 115. HOME philips transverse relaxation T2 Spin- Spin relaxation signal generation
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- 132. HOME philips S time Free Induction Decaysignal FID T2* signal generation transverse relaxation T2
- 133. HOME philips T2 S T2 63% definition T2: the timethat passes untill 63% of the original signal has been lost time signal generation transverse relaxation T2
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- 148. HOME philips 180º 180º refocusing pulse signalgeneration transverse relaxation T2
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- 150. HOME philips in conclusion: • T1relates to magnetisation • T2 relates to signal signal generation
- 151. HOME philips nuclei, protons andspins longitudinal relaxation T1 transverse relaxation T2 exitation and relaxation relation between T1 and T2 signal generation
- 152. HOME philips 0 time 100 Longitudinale and Transverse Relaxation: 90 o signalgeneration relation between T1 and T2
- 153. HOME philips 0 time 100 Longitudinale and Transversale Relaxation:at the same moment 90 o magnetisation signal signal generation relation between T1 and T2
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- 155. HOME philips short T1 short T2 0 time 100 90 o 90 o signalgeneration relation between T1 and T2
- 156. HOME philips long T1 0 time 100 90 o 90 o signal generation relationbetween T1 and T2
- 157. HOME philips long T1 long T2 0 time 100 90 o 90 o signalgeneration relation between T1 and T2
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- 163. HOME philips signal generation relation betweenT1 and T2 T1 contrast
- 164. HOME philips time 90 o longitudinal relaxation =magnetisation signal generation T1 contrast
- 165. HOME philips time 90 o magnetisation cannot bemeasured! signal generation T1 contrast
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- 172. HOME philips TE 10 msTE 30 ms TE 40 ms TR 400 ms signal generation T1 contrast
- 173. HOME philips T1 weighted images: TRshort TE short < 600 ms < 25 ms signal generation T1 contrast
- 174. HOME philips Fat bright bone marrow whitematter muscle grey body fluids bone air black grey matter TR < 600 ms TE < 25 ms i.v.contrast signal generation T1 contrast
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- 176. HOME philips Glioblastoma T1 T1 withGadolinium signal generation T1 contrast
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- 178. HOME philips T2 contrast signal generation relationbetween T1 and T2
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- 187. HOME philips TR 2500 ms TE20 ms TE 60 ms TE 100 ms TE 140 ms signal generation T2 contrast
- 188. HOME philips T2 weighted images: TRlong TE long > 1800 ms > 80 ms signal generation T2 contrast
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- 191. HOME philips T1 T1 +KM T2 signal generation T2 contrast
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