眶下神经起源于上颌神经，经眶下裂进入眼眶，与眶下动脉一起走行于眶底的眶下沟和眶下管，于眶下孔出眶。此神经损伤多见于眶底骨折，而眶爆裂性骨折多发生于眶底，其发生率为85%。临床表现多为同侧下睑中部，鼻翼皮肤、上唇皮肤和黏膜的感觉异常。分析原因：（1）外伤直接或间接所致的神经周围组织水肿导致眶下管内压力升高，神经严重受压；（2）累及眶下管、眶下沟、眶下孔的眼眶骨折，骨折处可直接压迫神经导致损伤。针对眶下神经损伤的治疗，有保守治疗和手术两种方案。至于哪种更有优势，尚无定论。

Infraorbital nerve originates in maxillary nerve which is the second branch of trigeminal nerve. It goes through inferior orbital fissure,then goes by inferior orbital groove and inferior orbital canal, at the end, it goes out of orbits at the inferior orbital foramen.Infraorbital nerve is highly vulnerable to damage in the fracture of orbital floor with the incidence of 85%. The clinical manifestations are featured by paresthesia of the middle of the ipsilateral lower eyelid, the nose skin and the upper lip skin and mucous membranes.The reasons can be analyzed: (1) optic nerve edema caused by trauma leads to the increasing internal pressure of inferior orbital canal；(2) the fracture line directly compresses the nerve.According to the therapy of the damage in inferior orbital nerve,there are conservative treatment and operative treatment. There is no final conclusion about which treatment is better.