Intro to Magnetic Resonance Imaging Using K-12 Concepts in Real-life, Hands-On Activities

Background: This learning unit aims to help students combine knowledge of K-12 STEM topics such as waves, electricity, magnetism, polar molecules and engineering design into exciting, real-world activities related to Magnetic Resonance Imaging (MRI). These activities are adapted for 4^th grade Common Core or 8^thgrade Next Generation Science and Engineering Standards. Methods: The unit is broken into steps of about 70 minutes each. 1. Idea: Waves have certain properties and high frequency waves are used in MRI. Project: Create waves (strum a guitar at different frequencies, drop different size pebbles in water, student choice) and explore wave properties. 2. Idea: There are different kinds of magnets and electromagnets are used in MRI. Project: Create an electromagnet using a metal bore, copper wire, and a battery. 3. Idea: Like magnets, certain molecules (especially water) have polarity. MRI uses the polarity of molecules to generate an image of the body. Project: Study and demonstrate properties of the polarity of water using a dropper, pennies, straws, and water. 4. Idea: Objects have a natural, or resonant, frequency at which they tend to vibrate when they are subject to vibrations near this frequency. Resoance between objects is used in MRI ( and this relates to the R in MRI). Project: Excite objects at their resonant frequencies using tuning forks, gourd drums, and rubber-band guitars. 5. Idea: A person’s molecules have a certain resonant frequency inside an MRI scanner. MRI uses very strong magnets and RF waves­­­ at the molecules’ resonant frequency to create anatomical images. Project: Explain/draw idea 5 by using an idea web and by connecting to concepts in steps 1-4. 6.  Idea: The field strength is most consistent and strongest at the center of an MRI scanner. Project: Create a “model MRI scanner” using the concepts from step 2 but with a hollow metallic tube instead of a metal bore. Measure the field strength around the electromagnet using a Gauss Meter. 7. Idea: The magnetic field of an MRI scanner is very strong. Project: Use the electromagnet from step 6 and vary the number of windings around the tube to study the changes in the magnetic field.  Compare the difference between the field strength of homemade electromagnet and clinical MRI scanners. Results: Using the engineering design process in each activity, students show understanding of MRI and STEM topics. Students demonstrate enthusiasm by completing a survey before and after the learning unit. Conclusion: In this project, students combine and apply knowledge of K-12 topics to understand the basics of MRI. The topics presented are consistent with grade 4 Common Core Standards and grade 8 Next Generation Standards. These concepts can be adapted to include students in other grade levels.