颈内动脉床突段与眼动脉关系的多层螺旋CT观察

Relationship of clinoid segment of internal carotid artery and ophthalmic artery:a study by multi-slice spiral CT scanning

目的利用多层螺旋CT(multi-slice spiral computed tomography,MSCT)三维重建在活体个性化观察颈内动脉(internal carotid artery,ICA)床突段与眼动脉(ophthalmic artery,OA)分支的关系。方法观察100例(200侧)受检者薄层轴位和容积再现(volume rendering,VR)融合图像上OA的起始位置,并将轴位ICA前半部分分成前内、中、外各1/3等分,分别记录OA起始点所在的位置;常规进行VR重建颅骨,沿眶截骨平面模拟切除颅盖骨,同时分别距前床突左或右外侧缘1 cm处模拟矢状位切除左或右外侧颅骨,并以正中矢状面将其分成左右两部分,于左或右侧分别观察OA与ICA的上下关系。结果 100例(200侧)受检者中,轴位上OA起始于ICA前、中、外1/3各占52.00%(左29.00%,右23.00%)、45.00%(左19.50%,右25.50%)和3.0%(左右各1.50%)。侧位上OA起始于OA段、床突段及其交界处者分别为76.50%(左39.00%,右37.50%)、6.00%(左、右侧各3.00%)、17.50%(左9.00%,右8.50%)。结论 MSCT能清楚地显示前床突、ICA床突段与OA起始部的关系,能为显微外科手术入路的选择和术中磨除前床突提供有用的影像学信息。

Objective To observe the relationship between the anterior clinoid process （ACP） of internal carotid artery （ICA） and ophthalmic arterial branch by multi-slice spiral computed tomography （MSCT） with three-dimensional imaging reconstruction. Methods A total of 100 patients’ （including 200 sides） ophthalmic artery （OA） opening was observed on the axial thin slice and volume rendering （VR） images. The anterior segment of axial ICA were divided into 3 parts according to its position from the axial superior surface of ICA, namely, the anterior-medial one-third, anterior-median one-third, and anterior-lateral one-third. Then the opening position of ophthalmic artery was recorded respectively. The VR technique was used to reconstruct the skull, by removing along superorbital 1.5-cm-superoccipital tuberosity 1.0 cm plane and the left or right lateral sagittal planes 1 cm to the lateral rim of the ACP in the simulation. Then the rest skull was divided into left and right parts along and median sagittal plane and integrated with the VR reconstruction of ICA with different color image respectively. The sagittal anatomy relationships between the ACP and ophthalmic artery opening position from the sagittal anterior surface of ICA were observed and recorded respectively. Results In 100 patients’ （200 sides） OA, 52.00% （left 29.00% and right 23.00%） came from above the medial one-third of the axial superior surface of ICA, 45.00% （left 19.50% and right 25.50%） from the median one-third, and 3% （right 1.50% and left 1.50%） from the lateral one-third. OA originated from proximally to the distal ring in 6% （left 3.00% and right 3.00%）, distally in 76.50% （left 39.00% and right 37.50%）, or closed to the distal ring in 17.50% （left 9.00% and right 8.50%）. Conclusion MSCT scanning clearly shows the relationship between the ACP, clinoid segment of ICA and OA opening, which can provide useful imaging information for the selection of operative approaches and removal of ACP in microsurgical operation.