Course Description
Discovered in 1977, magnetic resonance imaging (MRI) has become an increasingly popular imaging tool requiring no ionizing radiation, while producing high-quality, diagnostic images with excellent soft-tissue detail. MRI acquires images by producing a strong external magnetic field and radiofrequency (RF) pulses, while using the body's natural magnetic properties.

Hydrogen nuclei are used in MRI due to their abundance within the body and strong magnetism. When placed in a strong external magnetic field, hydrogen's magnetic field aligns and processes at a specific rate. Introducing an RF source at the same rate will cause resonance, increasing the hydrogen energy state. The release of this energy can then be measured by MRI coils. Pulse sequences apply RF pulses at predetermined intervals in order to take advantage of properties in various tissues and create diagnostic images with optimal visual contrast. Varying the timing and strength of these RF pulses creates a range of imaging options to enhance the radiologist's ability to make an appropriate diagnosis. 

In this chapter, we'll examine the basic fundamentals of MRI, understand how image contrast can be manipulated by pulse sequences, and discover advanced imaging techniques such as cardiac, functional, and 3-dimensional (3D) MR imaging. Advances in MRI continue to improve image quality, techniques, and patient experience, allowing for faster acquisition time and enhanced spatial resolution.

Learning Objectives
After reading the content, the participant should be able to:

• EXPLAIN the fundamental properties of MRI and how signal is produced to acquire an image.
• SUMMARIZE the importance of the linear gradient magnetic field and the ways in which it can manipulate the phase shift of hydrogen nuclei spins.
• IDENTIFY the relationship between spatial resolution and signal-to-noise ratio as well as the affect slice thickness can have on these properties.
• OUTLINE how spin echo and gradient-echo pulse sequences are used to achieve different image contrasts to demonstrate certain pathologies.
• IDENTIFY some advantages of advanced MRI techniques and how they distinguish MRI from other modalities.

 

Categories: Magnetic Resonance Imaging

In order to receive CE credit, you must first complete the activity content. When completed, go to the "Take CE Test!" link to access the post-test.

Submit the completed answers to determine if you have passed the post-test assessment. You must answer 14 out of 18 questions correctly to receive the CE credit. You will have no more than 3 attempts to successfully complete the post-test.

Participants successfully completing the activity content and passing the post-test will receive 1.75 ARRT Category A credits.

This program is approved by AHRA, a Recognized Continuing Education Evaluation Mechanism (RCEEM), approved by the ARRT to grant Category A CE credit.

Approved by the state of Florida for ARRT Category A credit.

Texas direct credit.

This activity may be available in multiple formats or from different sponsors. ARRT does not allow CE activities such as Internet courses, home study programs, or directed readings to be repeated for CE credit in the same biennium.

Category	Content Area	Credits
Magnetic Resonance	Image Production	1.75

Category	Subcategory	Credits
Magnetic Resonance	Data Acquisition, Processing, and Storage	0.5
Magnetic Resonance	Physical Principles of Image Formation	1
Magnetic Resonance	Sequence Parameters and Options	0.25

Category	Credits
Digital	0
Fluoroscopy	0
Mammography	0