Boren Rance A, Cloy Carson D, Gupta Ankur S, Dewan Vinay N, Hogan R Nick
Brownwood Regional Medical Center (RB, CC), Brownwood, Texas; and Department of Ophthalmology (AG, VD, RNH), University of Texas Southwestern Medical Center, Dallas, Texas.
J Neuroophthalmol. 2016 Dec;36(4):439-447. doi: 10.1097/WNO.0000000000000440.
Migration of intravitreal silicone to the retrolaminar optic nerve was detected pathologically in 1983, symptomatic migration to the subarachnoid space of the optic nerve was reported in 1994, and asymptomatic intraventricular silicone was first seen radiographically in 1999. Since then, little advance has been made in understanding this phenomenon despite numerous case reports. Although some authors have restricted their attention to cases of intraventricular silicone, we believe that these represent part of a clinical spectrum and that all cases with retrolaminar silicone should be considered. The pathophysiology of silicone migration may have significant implications for the management of patients after vitrectomy.
Two patients were evaluated by the authors. An internet-based literature review was conducted, beginning with the key search terms "intraventricular, intracranial, subarachnoid, or optic nerve silicone," and "complications of vitrectomy or intravitreal silicone." Further searches cascaded from the initial search results. An additional 24 cases of retrolaminar migration of silicone oil were found and summarized. The relevant anatomy and pathophysiology were reviewed, with attention to additional information from enucleation studies, as well as to gaps in the current understanding of this process.
Retrolaminar migration of silicone oil may be more common than previously thought, especially in at-risk patient groups, and may be associated with visual and neurologic symptoms. Some impressions regarding the cause and significance of this syndrome seem incorrect. Although this process is likely linked to postoperative elevations of intraocular pressure, the exact mechanisms of silicone entry into the subarachnoid space remain undefined. A number of anatomic factors may influence the movement of silicone from the orbit and in the various compartments of the subarachnoid space and ventricular system, resulting in variability of clinical presentations and radiologic findings. Implications for clinical decision making and directions for further research are discussed.
Greater awareness on the part of treating physicians, systematic study of at-risk populations, and advances in imaging technology will allow further insight into this phenomenon.
1983年在病理学上检测到玻璃体内硅油迁移至视神经管后段，1994年报告了有症状的硅油迁移至视神经蛛网膜下腔，1999年首次在影像学上发现无症状的脑室内硅油。自那时以来，尽管有大量病例报告，但在理解这一现象方面进展甚微。虽然一些作者将注意力局限于脑室内硅油病例，但我们认为这些只是临床谱系的一部分，所有视神经管后段硅油病例都应予以考虑。硅油迁移的病理生理学可能对玻璃体切除术后患者的管理具有重要意义。
作者对两名患者进行了评估。进行了基于互联网的文献综述，起始关键词为“脑室内、颅内、蛛网膜下腔或视神经硅油”以及“玻璃体切除术或玻璃体内硅油的并发症”。从初始搜索结果进一步展开搜索。另外发现并总结了24例硅油向后段迁移的病例。回顾了相关解剖学和病理生理学，关注摘出眼球研究的更多信息以及目前对这一过程理解中的空白。
硅油向后段迁移可能比之前认为的更常见，尤其是在高危患者群体中，并且可能与视觉和神经症状相关。关于该综合征病因和意义的一些观点似乎并不正确。虽然这一过程可能与术后眼压升高有关，但硅油进入蛛网膜下腔的确切机制仍不明确。一些解剖学因素可能影响硅油从眼眶以及在蛛网膜下腔和脑室系统各个腔隙中的移动，导致临床表现和影像学结果的差异。讨论了对临床决策的影响以及进一步研究的方向。
治疗医师提高认识、对高危人群进行系统研究以及成像技术的进步将有助于进一步深入了解这一现象。
