AdvancedTopic 91 of 102Manufacturing, Robotics & Systems
Medical imaging
X-ray, CT, MRI and ultrasound visualise the body.
In depth
X-ray/CT (attenuation, radiation dose), MRI (nuclear magnetic resonance with gradients and RF), ultrasound (echoes, Doppler), PET/SPECT (radiotracers) and optical methods reconstruct internal anatomy and function. Image reconstruction uses Fourier transforms and filtered back-projection, increasingly AI-assisted.
Key points
- Spatial and contrast resolution
- ALARA principle
- Signal-to-noise ratio
ExampleMRI uses 1.5–3 T magnets and radio waves to image soft tissue without ionising radiation.
What is Medical imaging?
X-ray, CT, MRI and ultrasound visualise the body.
Why is it important to understand medical imaging?
Medical imaging lets clinicians see inside the body without surgery, so imaging physics and signal processing are central to diagnosis.
What does X-ray imaging depend on?
Differences in X-ray absorption between tissues, which give contrast in the image.
How does MRI create images?
Magnetic fields and radio pulses excite hydrogen nuclei, and the signals they release are processed into images that show tissue differences.
How is Medical imaging used in practice?
Typical applications include creating a cross-sectional image of the head with CT, producing images of soft tissue with MRI for diagnosis and using ultrasound to check the heart in real time.
What should I learn before Medical imaging?
Study "Biomedical engineering" first (topic 90 of 102 in Manufacturing, Robotics & Systems). It covers the groundwork this topic builds on.
What are the key points of Medical imaging?
Spatial and contrast resolution. ALARA principle. Signal-to-noise ratio.
Can you give an example of Medical imaging?
MRI uses 1.5–3 T magnets and radio waves to image soft tissue without ionising radiation.
What comes after Medical imaging?
The next topic is "Prosthetics and rehabilitation", which builds directly on this one.
How difficult is Medical imaging?
It is classed as Advanced in Manufacturing, Robotics & Systems (topic 91 of 102). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Manufacturing, Robotics & Systems.