See what the scanner sees, and understand why.
Inside MRI breaks magnetic resonance imaging down into the physics, sequences, and anatomy that actually make a scan work — built for students, technologists, and anyone who's ever wondered what happens inside the bore.
Every scan starts with three ingredients.
No calculus required — just a clear picture of what the machine is actually doing to your body.
A very strong magnet
The main magnetic field lines up billions of hydrogen protons in your body, the way iron filings line up near a magnet — this alignment is what makes a signal possible at all.
A radio pulse
A precisely tuned radio wave knocks those protons out of alignment. As they fall back into place, they release energy the scanner can detect.
Gradient coils
Three smaller magnets vary the field across your body in each direction, giving every signal a location — this is how the machine knows where each pixel comes from.
From radio signal to finished image.
Every MRI, regardless of body part, follows the same four-stage pipeline.
Excite
An RF pulse tips protons in the chosen slice out of alignment with B0.
Encode
Gradient coils tag each returning signal with a position in space.
Receive
Coils near the body pick up the faint radio signal as protons relax.
Reconstruct
A Fourier transform turns raw signal data into the image on screen.
Six modules, taught the way a good mentor would.
Work through them in order, or jump to whatever you're stuck on this week.
Physics fundamentals
Spin, precession, and why hydrogen is the star of every scan.
Pulse sequences
Spin echo, gradient echo, and how timing shapes contrast.
K-space
The raw data grid behind every image, demystified with pictures.
Contrast & weighting
Reading T1, T2, and PD images like a radiologist does.
Safety & screening
Why the magnet never turns off, and what that means for you.
Clinical anatomy
Recognizing structures across the body's most common scan planes.
Get the next lesson before you need it.
One short, clear lesson a week — no spam, no stock photos of scanners, just the physics and practice that make MRI make sense.