超声测量视神经鞘直径在颅脑损伤患者中应用的临床进展
Clinical Progress of Ultrasonic Measurement of Optic Nerve Sheath Diameter in Patients with Traumatic Brain Injury

视神经是间脑的一部分，属于中枢神经的白质，通过视神经管进入眼眶，外面包有由三层脑膜延续而来的三层被膜，视神经鞘来源于硬脑膜，其内有充满脑脊液的蛛网膜下腔。脑脊液可在颅内和眼眶内蛛网膜下腔之间自由移动，眼眶内蛛网膜下腔压力变化与颅内蛛网膜下腔相同。当颅内压升高时，颅内和眼眶内蛛网膜下腔脑脊液充盈，ONSD会扩张增粗。同样颅内压降低也与视神经鞘蛛网膜下腔内脑脊液减少有关。因此在理论基础上，ONSD可反应颅内压变化。超声测量视神经鞘直径具有连续、动态、简便、安全等优点，尤其适用于重症患者的颅内压监测。本文就传统颅内压监测手段、超声测量视神经鞘直径在颅脑损伤中的应用及ONSD的局限性等部分对国内外相关研究进展进行综述，希望能为临床医生提供参考。
The optic nerve is a part of the diencephalon and belongs to the white matter of the central nervous system. It enters the eye socket through the optic nerve tube and is covered by three layers of meninges. The optic nerve sheath originates from the dura mater and contains a subarachnoid space filled with cerebrospinal fluid. Cerebrospinal fluid can freely move between the intracranial and orbital subarachnoid spaces, and the pressure changes in the orbital subarachnoid space are the same as those in the intracranial subarachnoid space. When intracranial pressure increases, the cerebrospinal fluid in the subarachnoid space of the skull and orbit becomes filled, and the ONSD expands and thickens. Similarly, the decrease in intracranial pressure is also related to the reduction of cerebrospinal fluid in the subarachnoid space of the optic nerve sheath. Therefore, on a theoretical basis, ONSD can reflect changes in intracranial pressure. Ultrasound measurement of optic nerve sheath diameter has the advantages of continuity, dynamics, simplicity, and safety, especially suitable for monitoring intracranial pressure in critically ill patients. This article reviews the research progress on traditional intracranial pressure monitoring methods, the application of ultrasound measurement of optic nerve sheath diameter in traumatic brain injury, and the limitations of ONSD both domestically and internationally. It is hoped that this can provide reference for clinical doctors.