TwinTree Insert

20-09 Magnetic Resonance Imaging Equipment

ith the exception of the scientific instrument manufacturers, the medical hard­ware makers had no background in NMR.

Very early NMR attracted the attention of Russel and Sigurd Varian, two bro­thers who were involved in military technology development in World War II. The Californian company became, first and foremost, a major government con­trac­tor for highly sophisticated and classified military technologies. NMR equip­ment for re­search remained an important sideline for the next 50 years (Figure 20-59).

Figure 20-59:
The Varian Associates site in San Carlos, CA, in 1948.

Other scientific manufacturers include JEOL in Japan and Bruker Spectro­spin in Ger­many and Switzerland. Most scientific developments connected to medical MR imag­ing were done on Bruker machines; even the competition used Bruker equipment inside their machines (Figure 20-60). Today Bruker is a US-American enterprise with a wide range of interests, from scientific equipment to military applications.

Figure 20-60:
A resistive Bruker whole-body MR machine from 1983. It operated at 0.15 T.

With few exceptions, most early magnets for MR machines were produced by Ox­ford Magnets. Still today many magnets stem from companies in the Oxford area, al­though nowadays many companies produce their own magnets.

The first hardware manufacturer to get involved in whole-body imaging was Elec­tric and Musical Industries (EMI) in 1974. Later the company was taken over by Picker (later Marconi, today Philips). Philips started research into MR imaging at the same time; P. Rob Locher, André Luiten (Figure 03-01b), and Piet van Dijk were seen at many scientific meetings. Siemens got involved in 1977, with — among others — Ar­nulf Op­pelt, Wilfried Loeffler and Andrew Maud­s­ley working on the project. Johnson & Johnson/ Technicare began their de­ve­lop­ment in 1978/79.

Others followed in the 1980s and 1990s, among them the big Japanese companies Hitachi and Toshiba, as well as the US-American General Electric company in 1983. To add to its competence and market in MR imaging, General Electric acquired Techni­care from John­son & Johnson in 1985, the French CGR in 1988, the MR business of the Israeli company Elscint in 1998 and, a little later, the former Nor­we­gian Nycomed contrast agent business.

M&D Aberdeen was a company originating from the research group at Aber­deen University. It had one machine in Geneva, but the company disappeared a long time ago.

Another effort was the Finnish MR imaging machine in the late 1970s, produced by Instrumentarium in Helsinki. Raimo E. Sepponen (Fi­gu­re 20-61), together with a number of other researchers, among them the sur­ge­on Jorma T. Sipponen, aimed to develop a method and device for detection of internal hemorrhages. Their first clinical MR imaging model was installed at Hel­sin­ki University Central Hospital in June 1982 operating at a field strength of 0.17 T. The second unit operated at 0.02 T, and later units operating at 0.04 T [⇒ Sepponen 1996]. This was — at least at that time — politico-commercially a step in the wrong di­rec­tion. Nowadays, such intelligent and sophis­ti­cat­ed approaches would be wel­comed again.

Figure 20-61: Raimo E. Sepponen.

spaceholder red

Some thoughts written after some decades of MR imaging …

inkpot The 30th anniversary

spaceholder red