管内段视神经损伤的诊断和疗效分析

Clinical analysis of traumatic optic nerve dysfunction

目的分析管内段视神经损伤所致视力障碍的诊断要点、疗效及影响愈后的因素。方法对２６例（２７侧）管内段视神经损伤继发视力障碍的患者，经眶部ＣＴ检查后，在药物治疗的同时，采用鼻外开筛进路视神经减压术治疗。结果该病的眶部ＣＴ检查总阳性率为６６７％，其中视神经管骨折阳性率为８１３％，视神经水肿阳性率为５５．６％。伤后立即出现视力障碍者有效率为５７．１％，非伤后立即出现视力障碍者有效率为８３３％。术中明确发现有视神经管骨折者有效率为５６．３％，仅见视神经水肿者有效率为６６．７％。手术时机愈晚，疗效愈差。结论眶部ＣＴ检查对管内段视神经损伤具有重要诊断价值，ＣＴ检查阴性不能除外该病；疗效与视神经损伤程度和手术时机等因素有关。

Objective To evaluate the key factors in diagnosis, treatment and prognosis of optic nerve trauma at the canalicular segment. MethodsWT5BZTwentysix patients with optic nerve dysfunction resulted from trauma to the nerve at canalicular segment were analyzed. All the patients received orbital CT scans, corticosteroid therapy and surgical optic canal decompression through the external ethmoid approach. Results With the help of CT scan, the total diagnostic rate was 66.7%; that for canal fracture was 81.3%, for nerve swelling 56.3%.The improvement rate of surgical decompression depended on the time of visual loss and types of toauma. Specifically, the improvement rate was 57.1% in patients with visual loss occurred immediately after the trauma, 83.3% in patients with visual loss occurred a moment after the trauma, 66.7% in patients with optic nerve swelling and 56.3% with optic canal fracture. The possibility of recovery decreased with delay of the surgery. Conclusion Orbital CT scan facilitates the diagnosis of optic canal fracture. However, the possibility of traumatic optic nerve dysfunction can not be ruled out in patients without the sign of canal fracture in the CT scan. The key factors in determining nerve recovery were associated with the severity of optic nerve trauma and the chance of surgery. Serious trauma and delay of the surgery may result in the blindness.