リアルタイムNMRビーム誘導速度マッピング. VモードNMRはVモードである
J D Pearlman1, J R Moore, M J Lizak
1Department of Medicine, Massachusetts General Hospital, Boston.
Circulation
|November 1, 1992
まとめ
Vモード核磁気共鳴 (NMR) は,どの角度からでも血流速度をリアルタイムで測定することができ,現在の技術の限界を克服します. この新しいMRIメソッドは,心臓および血管研究のための臨床的に重要なデータを提供します.
科学分野:
- メディカルイマージング (医学イメージング)
- 心血管生理学 心血管の生理学
- バイオメディカルエンジニアリング
背景:
- 現在の非侵襲的血流速度測定は,視界方向 (ドップラー超音波) や時間解像度 (MRI) に制限があります.
- リアルタイムで血液動力学的データを収集するための高度な技術が必要です.
- Vモード核磁気共鳴 (NMR) は,潜在的な解決策を提供します.
研究 の 目的:
- リアルタイムで血流速度を測定するためのVモードNMRの導入と評価.
- 任意の方向での技術の性能を評価する.
- その臨床的適用性を実証するために.
主な方法:
- 標準的な1.5-Tの臨床NMR画像機にVモードNMRを実装する.
- このテクニックを幽霊と人間のボランティアでテストする.
- 60Hzまでの速度の流れ速度のデータを取得します.
主要な成果:
- 幻の測定速度と実際の速度との高い相関関係 (r > 0.99) がある.
- 人間の下降性大動脈における血流の測定が成功しました.
- 大動脈不全患者の特徴的なバックフローの検出.
結論:
- VモードNMRは,臨床的に重要な血流情報のリアルタイム取得を可能にします.
- このテクニックは,任意の角度から測定を可能にします.
- 骨または空気-組織インターフェイスでの衰弱の影響を受けず,幅広い適用性を提供します.
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