Mansour Ahmad M, Mansour Hana A, Arevalo J Fernando
Department of Ophthalmology, Rafic Hariri University Hospital, Beirut, Lebanon ; Department of Ophthalmology, American University of Beirut, Beirut, Lebanon.
Department of Biology, American University of Beirut, Beirut, Lebanon.
Clin Ophthalmol. 2014 Nov 13;8:2243-50. doi: 10.2147/OPTH.S74163. eCollection 2014.
This patient presented for surgery at the age of 32 years, 14 months after his initial complaint of metamorphopsia and visual loss in the right eye. Past tests demonstrated a whitish epiretinal membrane (ERM) with translucent stress lines over a thickened macula. Visual acuity was found on last presentation to be normal with minimal alteration on Amsler grid testing. A torn ERM was found in the center with left-over ERM temporally and rolled-over ERM nasally at the site of the epicenter with no posterior vitreous detachment. Visual recovery occurred gradually over several days 2 months prior to presentation apparently following heavy weight-lifting with a sensation of severe eye pressure. Sequential funduscopy and optical coherence tomography scans demonstrated the peeling of an ERM accompanied by normalization of foveal thickness. Valsalva maneuver had put excessive tension on ERM which tore in its center at the weakest line with gradual contraction of the ERM away from the fovea towards the peripapillary area. This is a new mechanism of self-separation of ERM induced by Valsalva. ERM in young subjects is subject to rupture and subsequent separation by tangential traction. There are three mechanisms for spontaneous separation of ERM: 1) posterior vitreous detachment with pulling of ERM by detaching vitreous (most common in adults); 2) the contracting forces of the immature ERM become stronger than its adhesions to the retina resulting in slow tangential traction on the edges of the ERM and gradual separation from the edges towards the center (remodeling common in youngsters); and 3) acute tearing of ERM at its weakest central point and retraction of part of the membrane towards the epicenter (current case report).
该患者在初次抱怨右眼出现视物变形和视力丧失14个月后,于32岁时接受手术。既往检查显示在增厚的黄斑上有一个白色的视网膜前膜(ERM),伴有半透明的应力线。上次检查时视力正常,阿姆斯勒方格表测试仅有轻微改变。在中心发现一个撕裂的ERM,在震中部位颞侧有残留的ERM,鼻侧有翻转的ERM,无玻璃体后脱离。在就诊前2个月,患者在进行重物举重后明显感到眼内压力剧烈,随后几天视力逐渐恢复。连续的眼底镜检查和光学相干断层扫描显示ERM被剥离,同时黄斑厚度恢复正常。瓦尔萨尔瓦动作使ERM承受了过大的张力,导致其在最薄弱的部位中央撕裂,随后ERM逐渐从黄斑向视乳头周围区域收缩。这是瓦尔萨尔瓦动作诱发ERM自我分离的一种新机制。年轻患者的ERM易因切线牵引力而破裂并随后分离。ERM自发分离有三种机制:1)玻璃体后脱离,脱离的玻璃体牵拉ERM(在成年人中最常见);2)未成熟的ERM收缩力强于其与视网膜的粘连,导致ERM边缘缓慢的切线牵引力,并从边缘向中心逐渐分离(在年轻人中常见的重塑);3)ERM在其最薄弱中心点急性撕裂,部分膜向震中回缩(本病例报告)。