Clinical MR Imaging and Physics: A Tutorial

ISBN-13: 9783540779995 / Angielski / Miękka / 2008 / 188 str.

Haris S. Chrysikopoulos

Opis

Keywords Spin Electromagnetic radiation Resonance Nucleus Hydrogen Proton Certain atomic nuclei possess inherent magnetic Let us summarize the MRI procedure. Te patient properties called spin, and can interact with electro- is placed in a magnetic feld and becomes temporarily 1 magnetic (EM) radiation through a process called magnetized. Resonance is achieved through the - resonance. When such nuclei absorb EM energy they plication of specifc pulses of EM radiation, which is proceed to an excited, unstable confguration. Upon absorbed by the patient. Subsequently, the excess - return to equilibrium, the excess energy is released, ergy is liberated and measured. Te captured signal producing the MR signal. Tese processes are not is processed by a computer and converted to a gray random, but obey predefned rules. scale (MR) image. Te simplest nucleus is that of hydrogen (H), con- Why do we need to place the patient in a m- sisting of only one particle, a proton. Because of its net? Because the earth s magnetic feld is too weak to abundance in humans and its strong MR signal, H be clinically useful; it varies from 0. 3 0. 7 Gauss (G). is the most useful nucleus for clinical MRI. Tus, foC r urrent clinical MR systems operate at low, mid or our purposes, MRI refers to MRI of hydrogen, and for h igh feld strength ranging from 0. 1 to 3."

Recenzje

From the reviews:

"This introductory book is designed to take readers from the fundamentals of proton interactions to the interpretation of clinical MR imaging studies. ... All healthcare professionals are the intended audience. The book is certainly suitable for radiologists interested in MRI or MR technologists wanting to learn the essentials of the technique. ... provides a good starting point for those involved in MR imaging with a clinical perspective. It is well-illustrated and practically demonstrates how physical principles directly govern the images of any MR imaging study." (R. Terry Thompson, Doody's Review Service, March, 2009)

Spis treści

Resonance.- Electromagnetic Fields.- Macroscopic Magnetization.- Macroscopic Magnetization Revisited.- Excitation Phenomena.- T1 Relaxation (Longitudinal or Spin-Lattice Relaxation).- T2 Relaxation (Transverse or Spin–Spin Relaxation).- Magnetic Substrates of T1 Relaxation.- Magnetic Substrates of T2 Relaxation.- Proton (Spin) Density Contrast.- Partial Saturation.- Free Induction Decay.- Spin Echo.- Integration of T1, T2, and Proton Density Phenomena.- Inversion Recovery.- Image Formation – Fourier Transform – Gradients.- Gradient Echo Imaging.- Pulse Sequences.- Fast or Turbo Spin Echo Imaging.- Selective Fat Suppression.- Chemical Shift Imaging.- Magnetization Transfer Contrast.- Diffusion.- Artifacts.- Noise.- Imaging Time.- Resolution.- Contrast Agents.- Blood Flow.- MR Angiography.- Basics of MR Examinations and Interpretation.