Hellmuth Hertz invented medical ultrasound
Hellmuth Hertz was one of the pioneers of biomedical engineering in Lund. As early as the 1950s, the young physicist, together with cardiologist Inge Edler, was exploring how to use ultrasound to examine a functioning heart.
Today, ultrasound has overtaken radiography as the most used imaging technology in healthcare.
Hertz was part of the first generation of professors at LTH. Besides ultrasound, he also laid the foundations for another global success story, the inkjet printer. But in both cases it was in other countries that these innovations were developed into commercial successes.
Hertz died in 1990. A few years ago, his efforts were recognised in two different books. Former university vice-chancellor and physiologist Håkan Westling, together with Hellmuth’s colleague Lennart Grahm from the Department of Measurement Technology and Industrial Electrical Engineering, wrote “Med fysiken i blodet” (“With physics in his blood”). The book is about Hellmuth Hertz’s exciting life.
Growing up in Germany in a family of physicists with a father who was a Nobel prize-winner and a paternal uncle who gave his name to the Hertz frequency unit, and friends such as Albert Einstein, he ended up during and after the Nazi period being a prisoner of the Americans before physicists such as James Franck and Niels Bohr steered him towards professor Thorsten Gustafsson in Lund.
In professor Gustafsson’s family, Hertz found a new home and soon started a new career in the fifthies, from 1964 as a professor at LTH.
Cardiologist Inge Edler wanted a method to see into the heart and wondered whether radar could be used for this purpose. Radar had been developed during the war. Hertz didn’t think so, when he heard about the issue, but he came up with the idea of ultrasound which had been developed to detect submarines. It was on 20 October 1954 that a living human heart was first observed with a device borrowed from Kockum’s shipyard. The result was a usable two-dimensional eco-cardiography, showing the heart’s movements in real time. A camera in front of the oscilloscope recorded the images.
The second book from Lund is entitled “Ultrasound in Clinical Diagnosis” (published by the Swedish Royal Physiographic Society) and also describes the further development of ultrasound within medicine. At a symposium in the hospital auditorium last year, the book’s authors each presented their own section of the work, among them LTH professor emeritus Kjell Lindström, who was also head of biomedical engineering at SUS (Skåne University Hospitals).
Much of the subsequent development then took place among Lund physicians. Nils Rune Lindström tested the method on children’s hearts, Stig Jeppsson investigated children’s abdomens in Africa and Lars Leksell looked at bladders, Bertil Sundén in Lund and Ian Donald in Glasgow started on what ultrasound would become best known for, namely foetal examination. Several different malformations could be detected. Nowadays, 97 % of Swedish foetuses are examined in the 18th and the 32nd gestational weeks.
Doppler technology made it possible to visualise the flow of blood. Blood vessels such as the aorta can be examined and atherosclerosis can be discovered 15 years before symptoms appear. 80 000 Swedes are examined every year with ultrasound for cataracts, explained Bernt Ehinger.
“It was Sam Maslak at MIT who, in cooperation with Hewlett Packard (HP), produced the first ultrasound machines. Today, 6 billion dollars-worth of such machines are sold every year!” said Kjell LindströmUltrasound can also be used for treatments such as breaking up tumours and kidney stones. The development is continuing with increasingly sophisticated emitters and receivers, which can reproduce both 3D and 4D images. Today, the limits are set by computer power and electronics.
Text: MATS NYGREN