The development project for application of MR imaging to diagnosis of internal hemorrhages was initiated by the Instrumentarium Corporation in 1978. The goal was to develop a diagnostic tool for emergency clinics. Due to the rapid development of imaging technology, the goal was changed to a cost-effective MR unit.
During the past 16 years, several generations of low-field units have been introduced. Consequently, a vast amount of clinical and technical knowledge about low-field MR has been gained.
The interest in low-field units is rapidly increasing. A part of this may be explained by the pressure to reduce the cost of health care. There are some features which make the low-field approach clinically interesting. These include the feasibility of open magnet configurations, and the availability of unique contrast parameters such as magnetization transfer and T1ρ. One important aspect is the inherent safety of a low-field MR unit.
This article reviews the methods and devices introduced through the development of low-field technology in Finland.
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