Sahin Neslin, Mohan Suyash, Maralani Pejman J, Duddukuri Srikalyan, O'Rourke Donald M, Melhem Elias R, Wolf Ronald L
1 Department of Radiology, Sifa University School of Medicine, Fevzipasa Blvd 172/2, 35240 Basmane Izmir, Turkey.
2 Department of Radiology, University of Pennsylvania, Philadelphia, PA.
AJR Am J Roentgenol. 2016 Dec;207(6):1263-1270. doi: 10.2214/AJR.15.15119. Epub 2016 Sep 13.
The purpose of this study was to assign confidence levels to structural MRI and functional MRI (fMRI) for localization of the primary motor cortex.
Ninety-one fMRI studies with at least one motor task (178 hemispheres) were identified. Three anatomic assessments were used to localize the primary motor cortex: relation between the superior frontal sulcus and precentral sulcus; cortical thickness; and configuration of the precentral knob. In 105 hemispheres, interreader agreement was assessed for two investigators with different experience levels. Confidence ratings from 0 to 5 (0, no confidence; 5, 100% confidence) were assigned for fMRI and each anatomic localization method.
Cortical thickness had the highest confidence rating (mean, 4.90 ± 0.47 [SD]) with only one failure. The relation between the superior frontal sulcus and precentral sulcus had the lowest confidence rating (4.33 ± 0.91) with three failures. The greatest statistical significance was observed for the cortical thickness and superior frontal sulcus-precentral sulcus methods (post hoc Bonferroni test, p < 0.001). Confidence rating scores were significantly higher for the cortical thickness sign than for fMRI results (4.72 ± 0.54) for a single motor task (post hoc Bonferroni test, p = 0.006); however, the mean confidence rating for fMRI improved to 4.87 ± 0.36 when additional motor tasks were performed. Interreader differences were least for the cortical thickness sign (paired t test, t = 4.25, p < 0.001).
Cortical thickness is a better anatomic landmark than fMRI localization for assigning confidence regarding localization of the primary motor cortex; however, localization of motor function is more specific when combined with fMRI findings. Multiple techniques can be used to increase confidence in identifying the hand motor cortex.
本研究旨在为结构磁共振成像（MRI）和功能磁共振成像（fMRI）对初级运动皮层的定位确定置信水平。
确定了91项至少包含一项运动任务的fMRI研究（178个半球）。采用三种解剖学评估方法来定位初级运动皮层：额上沟与中央前沟之间的关系；皮质厚度；中央前结节的形态。在105个半球中，评估了两名经验水平不同的研究者之间的阅片者一致性。为fMRI和每种解剖定位方法分配了0至5的置信度评分（0表示无信心；5表示100%信心）。
皮质厚度的置信度评分最高（平均值为4.90±0.47[标准差]），仅有一次定位失败。额上沟与中央前沟之间的关系置信度评分最低（4.33±0.91），有三次定位失败。皮质厚度和额上沟 - 中央前沟方法具有最大的统计学意义（事后邦费罗尼检验，p<0.001）。对于单个运动任务，皮质厚度指标的置信度评分显著高于fMRI结果（4.72±0.54）（事后邦费罗尼检验，p = 0.006）；然而，当进行额外的运动任务时，fMRI的平均置信度评分提高到了4.87±0.36。皮质厚度指标的阅片者差异最小（配对t检验，t = 4.25，p<0.001）。
对于确定初级运动皮层定位的置信度而言，皮质厚度是比fMRI定位更好的解剖学标志；然而，结合fMRI结果时运动功能的定位更具特异性。可使用多种技术来提高识别手部运动皮层的置信度。
