MAGNETIC RESONANCE IMAGING (MRI) TECHNOLOGIST

Magnetic resonance imaging (MRI) technologists utilize the resonant frequency properties of atoms within a magnetic field to image anatomic and/or physiologic conditions of the body to assist physicians in the diagnosis of disease. They work primarily in hospitals and clinics.

Magnetic Resonance Imaging Certification and Registration

The American Registry of Radiologic Technologists (ARRT) offers both primary and post-primary pathways to Magnetic Resonance Imaging certification and registration as part of its mission to recognize qualified individuals in medical imaging, radiation therapy, and interventional procedures.

This course is the first part of an extensive course series about the most versatile medical imaging modality, MRI, and magnetic resonance in general. In the course we are going to discuss what magnetic resonance is and how it works in real life from magnets and coils through spins and tissue parameters to RF pulses and processing tools.

The topics aim to give a broad and detailed overview about the principles of both theoretical and practical magnetic resonance as well as cover the vast majority of the RF pulse types and techniques used today.

While some math, engineering or science background is definitely beneficial none of these are essential. The course is designed to start from the very basics and gradually reach a level of understanding which can readily be used in practice and extended with self-teaching later on.

The course is structured as follows:

• Introduction - This introductory lecture gives a brief overview about the entirety of magnetic resonance from the physical phenomenon to the signal detection.

• Signal & Contrast types - MRI is the most versatile medical imaging tool in terms of achievable contrast types and tissue information. This lecture discusses some of the most important ones of these as well as the principles of MR signal generation

• Relaxation parameters and simple sequences - Here we discuss relaxation in details including how to measure the relaxation time constants and we introduce the pulse acquire and the spin echo pulse sequences and the most often used contrast weightings

• Detection and spectra - This session covers the physical principles of signal detection by means of RF coils as well as the main processing of MR, the Fourier-transform. Then we discuss the properties of the resulted complex spectra

• Steady-state sequences - The fastest and highest SNR yielding sequences are the steady-state sequences. This session gives an extensive overview about their properties, pros and cons as well as the generated signal

• RF pulse - Introduction - An introductory lecture about the RF pulses in general and more specifically the low flip-angle approximation-based Fourier pulse design

• RF pulses - SLR design - The lecture introduces the concept of the SLR design as a tool for larger flip-angle pulse design. The different SLR filter types that yield RF pulse types are discussed in details

• RF pulses - Adiabatic pulses - In this section the family of adiabatic pulses are discussed by introducing the principle behind adiabatic rotation and the most often used pulse types

• RF pulses with gradient - The last session about RF pulses introduces the topic of slice selection as well as the spectral-spatial pulses for advanced excitation

• RF coils and the Transmit-Receive chain - The closing lecture of the course gives a broad overview about the path the RF waves traverse from pulse generation to acquired signal processing. The principles of RF coils are also discussed via the example of surface coil building closing the course with some practical tips

Quizzes: Test your knowledge by taking the quizzes at the end of each lesson. If you pass, well done! If you don't, you can review the videos and notes again or ask for help in the Q&A section.

Coding exercises: Some of the courses come with coding exercises to help the understanding of the given topic. These are implemented in Python. Probably the easiest way is to run them in VisualStudio Code or Jupyter Notebook. If you have no experience with python neither have a coding environment set up open the files with a text editor and copy paste the content to the online python editor on replit and press run. Please read the comments thoroughly throughout the files as the comments contain instructions and useful information

Who this course is for:

• Mainly for those who are interested in or are currently studying magnetic resonance and wish to have a deeper understanding of both the theoretical and the practical aspects.

• Everyone who is interested in a cool application of math and science (such background is not strictly required)