Symposium: Innovations in medical imaging
The Forum Medizintechnik-Pharma - an association that provides a recognised contribution to the development of the co-operative environment in medicine, technology and pharmaceuticals, met for a symposium in Germany this July.
Attended by representatives from member institutions, which number 560 from 14 countries (in Europe as well as the USA and Far East) it was chaired by Professor J. Ruediger Siewert MD, also chairman of the board of Heidelberg University Hospital, focused on medical imaging. This includes X-ray technology, encompassing all conventional technologies and computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US).
Innovations in X-ray technology focus on digital post-processing of image data and on automation and standardisation of examination workflow. Currently, PET-CT is experiencing a boom. The stand-alone PET (Positron Emission Tomography) has been fully replaced by the combination of PET and CT. In one scan PET-CTs provide images which allow precise interpretation, in terms of morphology as well as metabolism (NB: In our next EH issue we will publish an interview with Dr Thomas Beyer of Philips Medical Systems on this subject).
In recent decades MRI has developed into an eminently successful imaging modality. MRI advantages include non-invasiveness and non-ionisation, and it can be used in a wide range of applications. However, like any other physical procedure, MRI has limitations. As far as clinical applications are concerned, these limitations can best be described by the so-called ‘magic triangle’: the interdependence of signal-to-noise ratio (SNR), scan time and image resolution. The development of coil arrays for signal detection allowed parallel data capture and thus significantly accelerated the imaging process. Current research is looking at further scan acceleration and whether and how it can be reached with multi-channel coil arrays.
In ultrasound technology new developments and the two-dimensional Doppler technique provide unmatched spatial resolution. Optimisation of signal reception turned out to be insufficient to realise spatial resolution of less than 5 mm. In previous ultrasound technology the waveform of the pulse depended primarily on the transducer’s crystal properties and its backlash.
In modern compound wave generators, however, an electrical pulse which is adapted to the crystal properties avoids backlash and thus generates short micro pulses with clearer echo signals which significantly improve resolution.
All technological developments are driven by the need to provide the clinical user with high-quality, efficient and patient-friendly diagnostic imaging tools and methods. The symposium offered interesting insights in the state-of-the-art technology but also allowed a glimpse at the next generation of medical technology equipment. Report: Guido Gebhardt