Gartus Andreas, Geissler Alexander, Foki Thomas, Tahamtan Amir Reza, Pahs Gerald, Barth Markus, Pinker Katja, Trattnig Siegfried, Beisteiner Roland
Study Group Clinical fMRI at the Department of Neurology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Eur Radiol. 2007 Jun;17(6):1634-43. doi: 10.1007/s00330-006-0459-z. Epub 2006 Oct 12.
Functional magnetic resonance imaging (fMRI) performed by echo-planar imaging (EPI) is often highly distorted, and it is therefore necessary to coregister the functional to undistorted anatomical images, especially for clinical applications. This pilot study provides an evaluation of human and automatic coregistration results in the human motor cortex of normal and pathological brains. Ten healthy right-handed subjects and ten right-handed patients performed simple right hand movements during fMRI. A reference point chosen at a characteristic anatomical location within the fMRI sensorimotor activations was transferred to the high resolution anatomical MRI images by three human fMRI experts and by three automatic coregistration programs. The 3D distance between the median localizations of experts and programs was calculated and compared between patients and healthy subjects. Results show that fMRI localization on anatomical images was better with the experts than software in 70% of the cases and that software performance was worse for patients than healthy subjects (unpaired t-test: P = 0.040). With 45.6 mm the maximum disagreement between experts and software was quite large. The inter-rater consistency was better for the fMRI experts compared to the coregistration programs (ANOVA: P = 0.003). We conclude that results of automatic coregistration should be evaluated carefully, especially in case of clinical application.
通过回波平面成像（EPI）进行的功能磁共振成像（fMRI）常常会出现高度扭曲，因此有必要将功能图像与未扭曲的解剖图像进行配准，尤其是在临床应用中。这项初步研究对正常和病理大脑的人类运动皮层中的人工和自动配准结果进行了评估。十名健康的右利手受试者和十名右利手患者在功能磁共振成像期间进行简单的右手运动。由三位功能磁共振成像专家和三个自动配准程序将在功能磁共振成像感觉运动激活区域内一个特征性解剖位置处选择的参考点转移到高分辨率解剖磁共振成像图像上。计算专家和程序的中位定位之间的三维距离，并在患者和健康受试者之间进行比较。结果表明，在70%的情况下，专家在解剖图像上对功能磁共振成像的定位比软件更好，并且软件在患者中的表现比健康受试者更差（非配对t检验：P = 0.040）。专家和软件之间的最大差异为45.6毫米，相当大。与配准程序相比，功能磁共振成像专家之间的评分者间一致性更好（方差分析：P = 0.003）。我们得出结论，自动配准的结果应仔细评估，尤其是在临床应用中。
