脳動静脈奇形の感受性に基づいた特性評価

Susceptibility-Based Characterization of Cerebral Arteriovenous Malformations.

• Till M Schneider
• Markus Möhlenbruch
• Michael Denoix
• Mark E Ladd
• Martin Bendszus
• Sabine Heiland
• Sina Straub

抄録

目的:

本研究の目的は、脳動静脈奇形（AVM）の血管系の機能的特徴付けのために、脳動静脈奇形（AVM）全体の血液脱酸素化を探索することであった。

OBJECTIVES: The aim of this study was to explore blood deoxygenation across cerebral arteriovenous malformations (AVMs) for functional characterization of AVM vasculature.

材料および方法:

脳動静脈血管奇形患者15名をデジタルサブトラクションアンギオグラフィと3T磁気共鳴イメージングシステムを用いてプロスペクティブに検討した．デジタルサブトラクション血管造影でAVM nidus、主要供給動脈、主要排出静脈を同定し、AVM nidus、AVM関連の流入・流出血管、AVM関連以外の正常静脈の関心量を、造影3D飛行時間データ上に描画した。得られたボリュームは、定量的な感受性マッピングとフローデータに適用された。

MATERIALS AND METHODS: Fifteen patients with cerebral arteriovenous vascular malformation were prospectively studied by digital subtraction angiography and using a 3 T magnetic resonance imaging system, with which three-dimensional (3D) gradient echo data for the calculation of quantitative susceptibility maps, velocity-encoded 3D gradient echo data for 3D flow assessment, and contrast-enhanced 3D time-of-flight data were acquired.The nidus, major supplying artery, and major draining veins were identified on digital subtraction angiography, and volumes of interest of the AVM nidus, AVM-related inflow and outflow vessels, and non-AVM-related normal veins were drawn on coregistered contrast-enhanced 3D time-of-flight data. The resulting volumes of interest were applied to quantitative susceptibility mapping and flow data.

結果:

すべての患者で、給電動脈と仁脈の間、および仁脈と排液静脈の間で感受性の有意な段階的増加が認められた（Padjusted = 0.035、Padjusted = 0.007）。その結果、AVMの供給動脈と排液静脈の間では、正常なtransapillary blood deoxygenation-related susceptibilityが9.3%から50.9%の間で変化していることが明らかになった。尿道血流速度で正規化すると、この変化は尿道周囲血液製剤の存在と相関していた。脳AVMの平均帯磁率変化は、潮汐量で正規化した場合には、平均潮汐流速と逆相関していた。

RESULTS: All patients showed a significant stepwise increase in susceptibility between feeding artery and nidus as well as between nidus and draining vein (Padjusted = 0.035, Padjusted = 0.007, respectively). Results revealed between 9.3% and 50.9% of the normal transcapillary blood deoxygenation-related susceptibility change between the feeding artery and the draining vein of the AVMs. When normalized by nidal blood flow velocity, this change was correlated with the presence of perinidal blood products. The mean susceptibility change across cerebral AVMs normalized with nidal volume inversely correlated with mean nidal flow velocity.

結論:

脳AVM全体の血液脱酸素化を示す感受性の変化は、本研究で初めて示され、末梢血液製剤の存在と関連していた。脱酸素化測定はAVM血管系の機能的特徴付けとして役立つ可能性があり、個々の治療評価と可能なリスク層別化の可能性を提供する可能性がある。

CONCLUSIONS: Susceptibility changes indicating blood deoxygenation across cerebral AVMs were shown for the first time in this study and were associated with the presence of perinidal blood products. Deoxygenation measures may serve as functional characterization of AVM vasculature and may offer the potential for individual treatment assessment and possible risk stratification.