臨床整形外科49巻11号

2014年11月発行

誌上シンポジウム 運動器画像診断の進歩

頚髄イメージングの進歩と拡散MRIの将来展望

著者： 藤吉兼浩¹²³ 許斐恒彦¹²³ 畑純一²⁴ 小牧裕司²⁴ 山田雅之⁵ 疋島啓吾²⁴⁶ 岡野栄之² 戸山芳昭¹ 中村雅也¹

所属機関： ¹慶應義塾大学医学部整形外科 ²慶應義塾大学生理学 ³独立行政法人国立病院機構村山医療センター整形外科 ⁴実験動物中央研究所 ⁵藤田保健衛生大学医療科学部放射線学科 ⁶沖縄科学技術大学院大学

ページ範囲：P.959 - P.970

　水分子の制限された拡散に着目し，その拡散異方性を捉えようとする磁気共鳴像を拡散テンソルMRIまたは拡散テンソルイメージング(diffusion tensor imaging：DTI)と呼ぶ．また，拡散異方性の情報をトラクトすることにより得た画像を拡散テンソルトラクトグラフィ〔diffusion tensor (fiber) tractography：DTT〕という．現在では脊髄損傷や圧迫性脊髄症などにおいても臨床応用が可能となっており，大規模な多施設での検討が始まろうとしている．また近年，世界中で競争が始まったニューロンのネットワーク全容を解明しようとするコネクトーム(connectome)プロジェクトにおいても拡散テンソルは不可欠である．本稿では拡散テンソルの基本原理と最新の知見を概説するとともに，拡散MRIの将来展望について述べる．

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