Noninvasive techniques for assessing skeletal changes in inflammatory arthritis: imaging technique.

New imaging techniques such as ultrasound and MRI are likely to play increasing roles in the future management of patients with inflammatory arthritis, particularly those with rheumatoid arthritis and spondyloarthropathies. Ultrasound has a number of distinct advantages including its ability to scan multiple joints, safety, and immediately availability in clinic. MRI, however, is more sensitive and has a greater field of view because of its tomographic nature. Both modalities have the added advantage over radiography in that they can image soft tissue as well as bone. Dual X-ray absorptiometry already has an established role to play in the assessment of osteoporosis, but new techniques such as digital radiogrametry, quantitative CT, and ultrasound potentially will have a more important role to play in the future.