Han Seongsik, Kim Byung Jun, Suh Pae Sun, Moon Hye Hyeon, Kim So-Yeon, Yoon Jong-Tae, Kwon Boseong, Lee Deok Hee, Song Yunsun
From the Department of Radiologic Technology (S.H.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Advanced Therapies (B.J.K.), Siemens Healthineers Ltd., Seoul, Korea.
AJNR Am J Neuroradiol. 2025 Jun 3;46(6):1173-1179. doi: 10.3174/ajnr.A8672.
3D rotational angiography (3DRA) is a crucial diagnostic tool for assessing neurovascular diseases. Despite its superior spatial resolution, challenges arise in visualizing minute vasculatures. This study investigates the impact of voxel size on the spatial resolution and noise of cerebral 3DRA.
3DRA data from January 2022 to May 2022 were retrospectively analyzed, including a total of 10 patients with 50 small vessels (<1.0 mm in diameter) analyzed (5 vessels per patient). Using the Artis Q biplane angiography machine, 3DRA data sets were acquired and reconstructed at various voxel sizes ranging from 0.05 mm to 0.30 mm. Quantitative assessment included measurement of vessel visibility (maximum grayscale intensity within the vessel), vessel sharpness (slope of grayscale intensity calculated between 20% and 80% of maximum intensity), and background noise (standard deviation within a nonvascular region). Qualitative assessments-sharpness, noise, and overall image quality-were evaluated by 3 neuroradiologists.
A total of 50 vessels were analyzed quantitatively. Both the maximum intensity and slope of grayscale intensity at vessel walls decreased with increasing voxel size. There was a significant 2.94% increase in vessel intensity for every 0.05 mm decrease in voxel size ( < .001). Background noise significantly decreased as the voxel size increased ( < .001). Qualitatively, as the voxel size decreased, the sharpness of the image improved, and the amount of noise decreased. The overall image quality generally improved with decreasing voxel size. A good interrater agreement was observed among the neuroradiologists (κ = 0.601).
Voxel size significantly influences 3DRA image quality. Smaller voxel sizes enhance spatial resolution and overall image clarity despite increased noise and reduced field of view. Strategic application of smaller voxel sizes is crucial for detailed vascular assessments, such as aneurysm morphology and fine vascular structures.
三维旋转血管造影（3DRA）是评估神经血管疾病的重要诊断工具。尽管其具有卓越的空间分辨率，但在显示微小血管方面仍存在挑战。本研究调查了体素大小对脑部3DRA空间分辨率和噪声的影响。
回顾性分析2022年1月至2022年5月的3DRA数据，共纳入10例患者，分析其中50条小血管（直径<1.0 mm）（每位患者5条血管）。使用Artis Q双平面血管造影机，在0.05 mm至0.30 mm的不同体素大小下采集并重建3DRA数据集。定量评估包括测量血管可见性（血管内的最大灰度强度）、血管清晰度（在最大强度的20%至80%之间计算的灰度强度斜率）和背景噪声（非血管区域内的标准差）。3名神经放射科医生对图像清晰度、噪声和整体图像质量进行定性评估。
共对50条血管进行了定量分析。血管壁的最大强度和灰度强度斜率均随体素大小的增加而降低。体素大小每减小0.05 mm，血管强度显著增加2.94%（P<0.001）。背景噪声随体素大小的增加而显著降低（P<0.001）。定性分析显示，随着体素大小减小，图像清晰度提高，噪声量减少。整体图像质量通常随体素大小减小而改善。神经放射科医生之间观察到良好的评分者间一致性（κ=0.601）。
体素大小显著影响3DRA图像质量。较小的体素大小可提高空间分辨率和整体图像清晰度，尽管噪声增加且视野减小。对于动脉瘤形态和精细血管结构等详细血管评估，战略性地应用较小体素大小至关重要。
