瀬戸 洋平

Yohei SETO

東京女子医科大学八千代医療センターリウマチ・膠原病内科

Department of Rheumatology, Tokyo Women's Medical University Yachiyo Medical Center

キーワード : ultrasonography, rheumatoid arthritis, spondyloarthritis, gout, calcium pyrophosphate deposition

リウマチ性疾患領域における筋骨格エコーは，関節リウマチの早期診断への応用からはじまり脊椎関節炎や痛風，ピロリン酸カルシウム結晶沈着症などの結晶沈着性関節疾患といったリウマチ学の主要な疾患の評価にも広がりをみせている．高周波プローブとパワードプラ法の登場により，高い感度，信頼性をもって患者の病状や疾患のプロセスを観察可能となり，臨床研究における重要な評価手段の一つとして用いられるとともに，実診療でもその有用性が認知され今やリウマチ専門医や超音波検査技師の間でも最も高い関心を得ている分野といえるだろう．「関節エコー」は関節炎の早期診断と鑑別診断に有用で，疾患活動性評価に適している．多くの研究で単純Ｘ線検査では描出できない所見を検出可能で，身体診察よりも高い精度，再現性をもって実施できることが示されている．検査の標準化，患者レベルでのスコアリング方法のコンセンサスなど今後の課題も残るが，診療におけるアウトカムの改善とリウマチ学における疾患のより深い理解に寄与することが期待される．

The clinical application of musculoskeletal ultrasonography in rheumatology started with the use in early diagnosis of patients with rheumatoid arthritis, and now its role has expanded to evaluation of other common rheumatic diseases such as spondyloarthritis and crystal-associated arthropathy (i.e., gout and calcium pyrophosphate deposition disease). Introduction of high-frequency probes and power Doppler has enabled highly sensitive and reliable evaluation of a patient's condition and disease processes. Ultrasonographic assessments subsequently have become one of the important outcome measures in clinical studies, and its usefulness has been recognized in daily clinical practice. Ultrasonography is useful in early and differential diagnosis of inflammatory arthritis, and its property should be well adapted to evaluation of disease activity. Many data have proven that it is more sensitive and reliable than physical examination, and it can describe subtle pathology that cannot be detected by conventional radiography. Though further progress towards standardization of the technique and development of a consensus in scoring methods is needed, it is expected that ultrasonography will not only improve clinical outcomes but also contribute to gaining more insight into rheumatic diseases.