Question

In: Physics

Explain how Free Induction Decay contributes to creating a MRI image.

Explain how Free Induction Decay contributes to creating a MRI image.

Solutions

Expert Solution

A free induction decay curve is generated as excited nuclei relax. The amplitude of the FID signal becomes smaller over time as net magnetization returns to equilibrium. If transverse magnetization of the spins is produced, e.g. by a 90° pulse, a transient MR signal will result that will decay toward zero with a characteristic time constant T2 (or T2*); this decaying signal is the free induction decay.
The signal peaks of the echoes fall onto this T2 decay curve, while at each echo the signals arise and decay with T2*. The typical T2 relaxation times being of the order of 5-200 ms in the human body. The first part of the FID is not observable (named the 'receiver dead time') caused by residual effects of the powerful exciting radio frequency pulse on the electronics of the receiver.


Related Solutions

How does magnetic resonance image (MRI) allow us to see details in soft nonmagnetic tissue? Use/connect...
How does magnetic resonance image (MRI) allow us to see details in soft nonmagnetic tissue? Use/connect magnetic field related concepts learned in class.
Explain how public sector contributes to the economic development of a nation.
Explain how public sector contributes to the economic development of a nation.
Explain the process of RNAi and how it contributes to differential gene expression
Explain the process of RNAi and how it contributes to differential gene expression
What is the importance of knowing the steps involved in creating an image? Why can’t the...
What is the importance of knowing the steps involved in creating an image? Why can’t the technologist just place the patient under the collimator light and press the exposure button? How many different types of X-ray machines will you be working with as a student technologist or as a technologist? What should you expect to be similar, and what may be different?
Question 8 Choose the item below that describes the process of creating an image with the...
Question 8 Choose the item below that describes the process of creating an image with the lowest file size that still renders a good quality image. O optimization O multimedia O validation O bandwidth QUESTION 9 Choose the item that creates an image link to the school.htm page when the school.gif graphic is clicked. O <a href="school.html" src="school.gif" alt="school"> </a> O <a href="school.html"> <img src = "school.gif" alt = " school "> </a> O <img src =" school.gif "href ="...
Explain "clonal expansion" of lymphocytes and how it contributes to the features of adaptive immunity, such...
Explain "clonal expansion" of lymphocytes and how it contributes to the features of adaptive immunity, such as specificity, elimination of pathogens and memory.
how to use the bateman’s equations of decay with a long decay chain. Please provide and...
how to use the bateman’s equations of decay with a long decay chain. Please provide and example
Explain how each of the assumptions of perfect competition contributes to the fact that all decision...
Explain how each of the assumptions of perfect competition contributes to the fact that all decision makers in perfect competition are price takers. If the assumptions of perfect competition are not likely to be met in the real world, how can the model be of any use? Explain the difference between marginal revenue, average revenue, and price in perfect competition.
Describe the process of cultural diffusion and explain how it contributes to cultural leveling. Give an...
Describe the process of cultural diffusion and explain how it contributes to cultural leveling. Give an example
Explain how covalent catalysis contributes to the function of the serine protease. Examine each of the...
Explain how covalent catalysis contributes to the function of the serine protease. Examine each of the different major classes of proteases. In what way is the mechanism of each class similar, and different, to the serine protease mechanism?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT