How an ECG Records the Heart’s Electrical Activity
An ECG records tiny voltage differences created by the beating heart. Learn what the leads measure, how waveforms form and where artifacts arise.
Medical Technology
Medical Technology
How do MRI, CT, ultrasound, pacemakers and other medical devices work? Clear explanations of the signals, sensors and engineering behind modern care.
Medical Technology
How a Pulse Oximeter Estimates Blood Oxygen
A pulse oximeter uses red and infrared light to estimate blood oxygen. See how pulsatile absorption becomes SpO2 and why readings can be wrong.
Medical Technology
How Ultrasound Turns Echoes into a Moving Image
Ultrasound imaging converts timed echoes into moving pictures. Learn how the probe sends pulses, measures depth and handles resolution limits.
Medical Technology
How CT Builds Cross-Sectional Images
CT imaging turns many angled X-ray measurements into cross-sectional slices. Follow the scan, reconstruction and key dose-versus-detail trade-offs.
Medical Technology
How MRI Turns Radio Signals into an Image
An MRI scanner does not take a photograph of the body. It performs a carefully timed measurement: a strong magnetic […]