视神经管骨折高分辨率CT检查及准(斜)矢状位重建的影像特征

Characteristics of Imaging of High-resolution CT examination and reconstruction of quasi-sagittal images of optic canal fracture

目的探讨视神经管骨折高分辨率CT(HRCT)检查及准矢状位重建的影像特征及其临床应用价值。方法对19例视神经管骨折患者行层厚1.5mm,间距1mm的视神经管横轴位及冠状位HRCT扫描,并利用多平面重建技术重建准(斜)矢状位,对视神经管骨折的CT表现进行联合分析。结果视神经管骨折的直接征象表现为视神经管壁骨质连续性中断,可分为凹陷型、线状型、粉碎型、嵌入型、混合型5型;间接征象表现为蝶窦积血、筛窦积血、视神经增粗、泪滴征等。19例(22眼)中,单壁骨折17眼(77.3%),多壁骨折5眼(22.7%),其中内壁骨折14眼(63.6%),外壁骨折4眼(18.2%),上壁骨折6眼(27.3%),下壁骨折3眼(13.6%)。结论视神经管HRCT检查可清楚的显示视神经管骨折的部位及分型,进行准矢状位重建可提高骨折的检出率,可为临床诊断及选择治疗方案提供可靠的影像学依据。

OBJECTIVE To investigate the characteristics of imaging of CT with high-resolution CT（HRCT） examination and reconstruction of quasi-sagittal images of optic canal fracture,and evaluate the clinical value. METHODS Nineteen cases of patients with fractures of optic canal underwent thin layer （1.5mm thickness,1mm pitch） HRCT scanning in axial and coronal positions,and multiplanar reconstruction technique was used for quasi-sagittal reconstruction. And the united performances of HRCT were analyzed. RESULTS The direct sign of the optic canal fracture was the interruption of the continuity of the wall,including 5 types：depression type,line type,crusing type,embedded type and mixed type. The indirect signs were hematocele sphenoid,ethmoid hematoma,optic nerve thickening and teardrop sign. In the 19 cases （22eyes） of optic canal fracture,single-walled fractures 17 eyes （77.3%）,multi-walled fractures 5 eyes （22.7%）. Fractrues of 14 eyes （63.6%） were on the medial wall,fractrues of 4 eyes （18.2%） were on the lateral wall,fractrues of 6 eyes （27.3%） were on the superior wall,fractures of 3 eyes （13.6%） were on the inferior wall. CONCLUSIONS HRCT examination of the optic canal could clearly show the site of fracture and its sub-type,and quasi-sagittal reconstruction might improve the detection rate of fracture. It could provide reliable imaging basis for the clinical diagnosis and treatment selection.