Right now, the timeframe for a market-ready PET/MRI product is still to be nailed down, though Siemens points out that the machine is already being used to generate in vivo human-brain PET/MRI images at its facilities in the US. Full-on testing starts later this year. Executives, for their part, are predicting that PET/MRI has the potential to become the modality of choice for neurological investigations, certain forms of cancer, stroke, and the emerging study of stem-cell therapy.

From a commercial perspective, the fusion of PET and MRI is a logical progression. Scanners that combine PET with CT have been around for about a decade, and were rapidly adopted for routine clinical diagnostics. In fact, in recent years more than 90% of all PET scanners purchased have been combined PET/CT systems - a clear demonstration of the value of integrated molecular and anatomical imaging.

Convergence, though, has implications beyond the core imaging technologies. For starters, research in medical imaging is becoming a more multidisciplinary affair, with radiologists and nuclear-medicine specialists working not only with clinicians from other disciplines but also with physicists, biochemists, physiologists, computer specialists and biomedical engineers. In the clinical setting, while multimodal imaging systems have enormous potential for efficient diagnosis, they also challenge established patterns of professional practice and patient care.

Working together

One thing is clear: effective coordination and communication are going to be essential as the boundaries blur between previously discrete disciplines. With this in mind, the European Society of Radiology (ESR) and European Association of Nuclear Medicine (EANM) have put their heads together and agreed a common position paper in an effort to encourage best practice in multimodality imaging - at least from the European perspective.

The timing of the white paper looks apposite, especially given the emphasis it places on joined-up training programmes. The ESR/EANM proposals specify training models aimed at "providing opportunities for acquisition of special competency certification in multimodality imaging". Significantly, both organizations also commit to work together on common procedural guidelines to coordinate the purchasing and management of hybrid imaging systems and ensure appropriate reimbursement of multimodal examinations.

Another core theme of the document is European research on multimodal technologies. "The coming years will decide whether European research in this area manages to defend its leading position or whether it falls back behind other leading economies," write the authors. "Since research teams in the [EU] member states are not always interconnected, more European input is necessary to create interdisciplinary bridges between research institutions."

Put another way: Europe not only has to get different disciplines working together; it must also get scientists working effectively on a pan-European basis. Operationally, the ESR and EANM plan to facilitate cross-border collaborations through the European Institute for Biomedical Imaging Research (EIBIR), a body funded by the EU Commission and several leading equipment makers. Top of the agenda at the EIBIR is the creation of a network of excellence to pull together fundamental and clinical research programmes in diagnostic imaging, mechanical and electronic engineering, informatics and biostatistics, and epidemiology.

As an exercise in prioritization, the ESR/EANM white paper looks eminently sensible and, just as important, achievable. As always, though, it's the execution - both near and longer term - that will determine whether this stuff remains largely aspirational or something more substantive.

• To download the ESR:EANM white paper in full, click here.