# [TECH] MRI (Magnetic Resonance Imaging)

**MRI** applies NMR physics with spatial magnetic field gradients to create detailed images of soft tissue in living patients, revolutionising medical diagnosis.

## Overview

Paul Lauterbur (1973) proposed using magnetic field gradients to spatially encode NMR signals. Peter Mansfield developed echo-planar imaging (1977), enabling fast whole-body imaging. The first clinical MRI system (Fonar, 1980) was installed in hospitals. Functional MRI (fMRI) maps brain activity (1990s). Modern 7-Tesla systems image sub-millimetre anatomy. MRI requires large superconducting magnets (from BCS theory) and sophisticated signal processing — a direct product of the semiconductor and computing revolutions.

## Key Actors

- **Companies**: GE Healthcare, Siemens Healthineers, Philips Healthcare, Fonar (first MRI system), Bruker
- **Inventors**: Paul Lauterbur (1929–2007), Peter Mansfield (1933–2017)

## Key Patents

- Lauterbur, P. US Patent 3,974,402 (1976) — MRI imaging
- Damadian, R. US Patent 3,789,832 (1974) — NMR tissue characterisation

## Economic Value

Global MRI market: **\$USD 8 billion/year** (2023, Grand View Research). Broader diagnostic imaging market: \$USD 40B/year. Healthcare decisions based on MRI prevent unnecessary surgery and improve outcomes worth \$USD 200B+/year globally.

## Notes

Grand View Research *MRI Market* 2023. **Nobel Prize 2003** awarded to Lauterbur and Mansfield. The value of early cancer detection enabled by MRI is included in the broader diagnostic imaging estimate.

## What This Enables

- **[TECH] Medical Imaging (X-ray, CT, PET)** — MRI is the most advanced soft-tissue imaging modality and anchors the broader diagnostic imaging market.

# Parents

* [SCI] Nuclear Magnetic Resonance (NMR)
* [SCI] Nuclear Magnetic Resonance (NMR)
* [SCI] BCS Superconductivity
* [SCI] Cryogenics