Department of Radiology, Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
AJNR Am J Neuroradiol. 2010 Jun;31(6):1076-9. doi: 10.3174/ajnr.A1992. Epub 2010 Jan 21.
The cisternal segment of the trochlear nerve is difficult to identify reliably by routine MR imaging. We investigated the visibility and anatomic features of the trochlear nerve by using high-resolution 3D-bTFE imaging in healthy subjects.
This study was conducted with 32 healthy subjects without ocular movement disorders. For us to visualize the cisternal segment of the trochlear nerve, all subjects underwent 3D-bTFE imaging at 3T with 2 different resolutions: conventional resolution (voxel size, 0.67 x 0.45 x 1.4 mm) and high resolution (voxel size, 0.3 x 0.3 x 0.25 mm). Visibility of the trochlear nerve was graded with the use of a qualitative scale of certainty as follows: definite, probable, and indeterminate. The diameter of the trochlear nerve was measured.
On conventional-resolution images, the visibility of the trochlear nerve was definite in 3 nerves, probable in 12 nerves, and indeterminate in 49 nerves. On high-resolution images, visibility was definite in 63 nerves and probable in 1 nerve. The mean diameter of the trochlear nerve was 0.54 mm (range, 0.35-0.96 mm).
The trochlear nerve was visualized 100% of the time on high-resolution imaging with a voxel smaller than the nerve diameter. High-resolution imaging should have an important role in investigating the pathogenic mechanism of neuropathic strabismus, such as congenital superior oblique palsy.
滑车神经的池段在常规磁共振成像（MR）中很难可靠识别。我们通过对健康受试者的高分辨率 3D-bTFE 成像来研究滑车神经的可视性和解剖特征。
本研究纳入了 32 名无眼球运动障碍的健康受试者。为了使我们能够可视化滑车神经的池段，所有受试者均在 3T 下接受了两种不同分辨率（体素大小分别为 0.67×0.45×1.4mm 和 0.3×0.3×0.25mm）的 3D-bTFE 成像。使用确定性的定性评分标准对滑车神经的可视性进行分级，分别为明确、可能和不确定。测量滑车神经的直径。
在常规分辨率图像上，3 条神经的滑车神经可视性为明确，12 条神经为可能，49 条神经为不确定。在高分辨率图像上，63 条神经的可视性为明确，1 条神经为可能。滑车神经的平均直径为 0.54mm（范围，0.35-0.96mm）。
在体素小于神经直径的高分辨率成像上，滑车神经的可视性为 100%。高分辨率成像应该在研究神经源性斜视（如先天性上斜肌麻痹）的发病机制方面发挥重要作用。
