What's the difference between MRI and CT?#
Step 1 — MRI in patient terms#
You lie still inside a tube (or open design) while magnets align hydrogen atoms in your body. Soft tissues — brain, discs, ligaments — show detail that CT sometimes misses. Claustrophobia and implanted devices require screening beforehand. Once you have the disc, our free MRI viewer opens the sequence list (T1, T2, FLAIR, DWI) in the browser.
Step 2 — CT in patient terms#
A ring-shaped gantry spins an X-ray tube; detectors measure how much beam passes through you. The math rebuilds slices in seconds. Trauma bays love CT because speed matters; stroke protocols often start with CT before MRI arrives. Our free CT viewer opens the same DICOM folder with adjustable window/level for lung, bone, and soft-tissue views.
Step 3 — Why your doctor picked one#
They weigh suspicion (tumour vs fracture), urgency, pregnancy, kidney function, and hardware compatibility. You can ask politely why MRI followed CT or vice versa — the answer educates you without second-guessing their training.
Step 4 — "Which is better?"#
Wrong question. Ask "Which answers today's clinical question with the least risk?" Sometimes the answer is both at different times. OpenMyScan displays either stack once you have the files; it does not choose modalities for you.
Step 5 — Opening both in OpenMyScan#
Copy each study into its own folder, drag them in separately, and use the sidebar to hop between series. CT window presets differ from MRI — if an image looks extreme, reset windowing before assuming something broke.
What goes wrong after the scan?#
- I received both MRI and CT discs
- Label folders by date and modality so you do not merge them accidentally.
- The report mentions "artifact"
- That usually means imaging noise — not automatically a finding in your body.
- I'm anxious about radiation from CT
- Ask your team for numbers in context; they balance dose against what the scan adds for your care.
- MRI was cancelled because of my implant
- Bring your device card next time — some implants are safe only at certain MRI magnet strengths (most scanners are 1.5 Tesla or 3 Tesla).
Common questions#
Do I need contrast for my scan?
Sometimes. Contrast changes what radiologists can see, but allergies and kidney issues matter — the ordering team decides.
Is a CT dangerous because of radiation?
A single clinically indicated CT is usually a small dose relative to benefit; ask if you are pregnant or had many prior scans.
Which is louder?
MRI. CT is mostly quiet aside from motion instructions.
Does this work offline?
Yes, after the first successful load. OpenMyScan caches in your browser, so you can use it on a plane or without WiFi as long as the page loaded once. Your files stay local either way.