Where is imaging going in rheumatology?

Four new approaches to imaging are now becoming available. First is filmless radiology, with flat detectors that 'permit access' to PACS, the picture archiving communication system, and teleteaching. Second is ultrasonography (US), involving three-dimensional volume, harmonic Doppler energy and digital technology techniques, with contrast agents and biopsy needles. Next is computer tomography (CT), using volume acquisition multislices, spiral reconstruction and solid detectors, as well as multidetectors. Finally comes magnetic resonance imaging (MRI). A low magnetic field with an open MRI scan permits interventional radiology in musculoskeletal disease. High magnetic fields are mainly used for clinical research and permit rapid examination, in approximately 10 minutes. In interventional radiology, many procedures can be performed with the guidance of digital radiography, US or MRI. Two areas of localization have to be considered: the spine and the peripheral joints, particularly the shoulder, wrist and foot. Guidelines contribute to good medical practice, but there are other considerations, such as machine accessibility, the nature of the treatment, the personality of the patient and the role of the hospital. Overinvestigation has to be avoided for four reasons: an increase in patient anxiety, the cost of health-care management, the risk of irradiation and sometimes the lack of diagnostic value of these procedures. In rheumatoid arthritis, MRI can detect lesions at an earlier stage of their development and identify subtle lesions and synovitis. Imaging (using x-rays, MRI and US) is important in the assessment of the effectiveness of slow-acting drugs in rheumatoid arthritis, especially since joint damage can progress in spite of a clinical improvement in joint inflammation. In the future, teletransmission, by the Internet or intranet and using PACS, will change our approach to the diagnosis of musculoskeletal disease. Future developments therefore include PACS, filmless radiology, the Internet and intranet, harmonic US, multidetector CT scanning and open MRI on the technical side, as well as the study of cartilage and international radiology on the clinical side.