Ikeda H, Yoshimoto T
Department of Neurosurgery, Tohoku University School of Medicine, Sendai, Japan.
Acta Neurol Scand. 1995 Aug;92(2):157-60. doi: 10.1111/j.1600-0404.1995.tb01031.x.
To clarify the relationship between visual disturbances caused by pituitary adenomas and the degree of chiasmal compression, MRI (1.5T) findings were assessed two dimensionally.
50 cases of pituitary adenomas and 17 control cases were studied. The position of the optic chiasm was measured by the distance from the line of the frontal base and posterior clinoid process on the sagittal T1 weighted image, and from the upper surface of the bilateral internal carotid artery on the coronal T1 image.
Visual disturbances appeared when the chiasm was displaced to more than 8 mm above the aforesaid reference level on the sagittal image and more than 13 mm above on the coronal image. There was a good correlation between the appearance of visual field defects and the degree of chiasmal compression.
The degree of chiasmal displacement measured by MRI two dimensionally can provide useful information for predicting the appearance of visual disturbances.
为阐明垂体腺瘤引起的视觉障碍与视交叉受压程度之间的关系，对MRI（1.5T）检查结果进行二维评估。
研究了50例垂体腺瘤患者及17例对照者。在矢状位T1加权像上，通过测量视交叉与额底和后床突连线的距离，以及在冠状位T1像上测量视交叉与双侧颈内动脉上表面的距离，来确定视交叉的位置。
当视交叉在矢状位图像上移位至上述参考水平上方超过8mm，在冠状位图像上移位至上述参考水平上方超过13mm时，出现视觉障碍。视野缺损的出现与视交叉受压程度之间存在良好的相关性。
通过MRI二维测量的视交叉移位程度可为预测视觉障碍的出现提供有用信息。
