FLASH MRI

Fast Low Angle Shot, the Göttingen imaging method that cut MRI scan times by a factor of about 100. It is the Max Planck Society's most lucrative patent, with about 155 million euros in licence income.

Made by: Max Planck Society
From: Munich, Bavaria
Category: Health & Life Sciences
Introduced: 1985

What it is

FLASH (Fast Low Angle SHot) is a way of collecting magnetic resonance images quickly. It was developed by Jens Frahm, Axel Haase and colleagues at the Max Planck Institute for Biophysical Chemistry in Göttingen. The German patent application was filed on 12 February 1985; the US patent followed in 1987 and the European patent in 1989.

How it works

Classic MRI tipped the magnetisation of hydrogen nuclei by a large angle and then had to wait for it to recover before the next measurement. FLASH uses a gradient echo and a small flip angle, exciting only a fraction of the protons each time. Because most of the magnetisation stays in place, measurements can follow each other almost immediately. Scan times fell from minutes to seconds, by a factor of at least 100.

Why it stands out

FLASH made routine 3D imaging and moving images of the heart practical, and manufacturers adopted it within months. General Electric, Siemens and Philips first opposed the patents and used the method anyway. The Max Planck Society and its transfer company fought for years; Siemens took a licence in 1992 and the others followed, with a final judgment in 1993. Licence fees totalled about 155 million euros, the largest sum in the history of Max Planck Innovation. In 2010 Frahm's team presented FLASH2, real-time MRI at up to 100 images per second.

Where you meet it

The patent has expired, but the technique is in every modern scanner; Siemens still uses the name FLASH for its sequence. The Max Planck Society says around 100 million MRI scans a year use it. Frahm received the European Inventor Award in 2018.

The licence history is a model case for European technology transfer: early filing, firm defence of the patent and a modest royalty across a whole global industry.

Sources

Stories

Innovations4 November 2026

How a Göttingen MRI trick became the Max Planck Society's most lucrative invention

In 1985 a small team in Göttingen made MRI a hundred times faster. Then they spent years fighting GE, Siemens and Philips in court. The result: about 155 million euros and a technique in every scanner.

Read the article

Explainers4 November 2026

German science you use every day without knowing

Your alarm clock, your MRI scan, your Netflix stream and the map in your phone all lean on work done in German research institutes. Here is where, who and how it got out of the lab.