小児腫瘍学における胸部MRI：造影後自由呼吸下3次元T1強調画像の有用性と画質

Thoracic MRI in Pediatric Oncology: Feasibility and Image Quality of Post-Contrast Free-Breathing Radial 3D T1 Weighted Imaging.

抄録

:胸部MRIを受ける小児腫瘍患者において、造影後自由呼吸radial stack-of-stars 3D T1w turbo-field echo Dixonシーケンス（3D T1w VANE mDIXON）と従来のカルテジアン息止め3D T1w fast-field echo mDIXONシーケンスの実行可能性と画質を比較する。合計48人の小児（女性34人、平均年齢5.3±3.7歳）が造影胸部MRIを受け、24人が3D T1w VANE mDIXONシーケンスで、24人が従来の息止め3D T1w mDIXONシーケンスで検査を受けた。画質は3人の放射線科医が独立して5点満点で評価した。信号対雑音比（SNR）は、血管や信号の不均一性を避けながら、均質な傍脊柱筋領域（SNR）と肝尖部（SNR）の2つの解剖学的部位で測定した。呼吸性アーチファクトの有無、総撮影時間、全身麻酔または鎮静の必要性が記録された。観察者間一致はFleissのκ（0）を用いて判定し、平均SNR値は独立標本検定を用いて群間で比較した。3D T1w VANE mDIXONシーケンスでは、SNRおよびSNRが有意に高く（530±120；570±110 vs 370±110；400±90；＜0.001）、診断画質は約25％改善し、呼吸性アーチファクトは約23％減少した。観察者間の一致はほぼ完璧であった。重要なことは、3D T1w VANE mDIXONを使用した場合、全身麻酔の必要性が有意に減少したことである（< 0.001）。自由呼吸下3D T1w VANE mDIXON胸部MRIは、小児がん患者にとって実現可能で効果的な撮像法であり、従来の方法と比較して優れた画質を提供し、全身麻酔の必要性を減少させる。

: To compare the feasibility and image quality of a post-contrast free-breathing radial stack-of-stars 3D T1w turbo-field echo Dixon sequence (3D T1w VANE mDIXON) with a conventional cartesian breath-hold 3D T1w fast-field echo mDIXON sequence in pediatric oncology patients undergoing chest MRI. : A total of 48 children (34 females; mean age 5.3 ± 3.7 years) underwent contrast-enhanced chest MRI, with 24 examined using the 3D T1w VANE mDIXON sequence and 24 with a conventional breath-hold 3D T1w mDIXON sequence. Image quality was independently assessed by three radiologists using a 5-point scale. Signal-to-noise ratio (SNR) was measured at two anatomical sites, a homogeneous paraspinal muscle region (SNR) and the liver apex (SNR), while avoiding vessels and signal inhomogeneities. The presence of respiratory artifacts, total imaging time, and the need for general anesthesia or sedation were recorded. Interobserver agreement was determined using Fleiss's kappa (ϰ), and mean SNR values were compared between groups using an independent samples -test. : The 3D T1w VANE mDIXON sequence yielded significantly higher SNR and SNR (530 ± 120; 570 ± 110 vs. 370 ± 110; 400 ± 90; < 0.001), improved diagnostic image quality by approximately 25%, and reduced respiratory artifacts by about 23%. Interobserver agreement was almost perfect. Importantly, the need for general anesthesia was significantly reduced using the 3D T1w VANE mDIXON ( < 0.001). : Free-breathing 3D T1w VANE mDIXON chest MRI is a feasible and effective imaging approach for pediatric oncology patients, offering superior image quality and reducing the need for general anesthesia compared to conventional methods.