脉络膜厚度测量在眼病诊断及病情监测中的应用

增强深部成像的相干光断层扫描技术(enhanced depth imaging optical coherence tomography,EDI-OCT)是在传统频域相干光断层扫描技术(optical coherence tomography,OCT)的基础上改进的能反映脉络膜组织结构的技术,可以定量测量脉络膜厚度,初步检测脉络膜血流情况,是一种简单、快捷、经济、实用的新方法,为临床相关研究提供了依据.目前,以健康人脉络膜厚度的研究为基础,这一技术已经用于多种眼底疾病特别是黄斑部疾病如中心性浆液性脉络膜视网膜病变、老年性黄斑变性、息肉状脉络膜血管病变、高度近视、糖尿病性视网膜病变黄斑水肿、黄斑裂孔等的研究中,取得了一定进展.     

湿性年龄相关性黄斑变性OCT特点与视力的相关研究

目的 研究湿性年龄相关性黄斑变性OCT图像特征与患者视力的相关性.方法 纳入湿性年龄相关性黄斑变性患者106例106只眼,记录患者最佳矫正视力(EDTRS视力),并对患者眼底进行光学相干断层扫描分析,统计黄斑区视网膜厚度、黄斑区总容积、测量脉络膜新生血管膜厚度,脉络膜新生血管与黄斑中心凹距离.结果 患者视力与脉络膜新生血管病变的最大线性距离、黄斑区总容积、CNV厚度、CNV距中心凹距离呈明显相关关系(P＜0.05).结论 湿性年龄相关性黄斑变性患者中心视力与脉络膜新生血管病变的位置、大小、视网膜水肿程度明密切相关.     

息肉样脉络膜血管病变的诊断及治疗

息肉样脉络膜血管病变(polypoidal choroidal vasculopathy,PCV)特征是后极部视网膜下桔红色息肉样病变,伴有出血性和浆液性视网膜色素上皮及神经上皮脱离.荧光素眼底血管造影无特征性表现,吲哚青绿血管造影能显示分支血管组成的脉络膜血管网和血管末端息肉样或动脉瘤样扩张.OCT表现为视网膜色素上皮及脉络膜毛细血管高反射层呈陡峭的穹窿状隆起,其下见中等反射或结节状改变.本病应与湿性年龄相关性黄斑变性和某些长期不愈的中心性浆液性脉络膜视网膜病变进行鉴别.尽管PCV的治疗仍缺乏通用的方案,光动力疗法结合玻璃体内注射血管内皮生长因子抑制剂可改善或稳定患者视力.     

特发性息肉样脉络膜血管病变

特发性息肉样脉络膜血管病变是近10多年来提出的一种疾病,病因不明,病变位于脉络膜血管层,有不同粗细的分支血管的血管网,分支血管终端伸入浆液性或出血性脱离的色素上皮和神经上皮之间,并扩张成动脉瘤样或息肉样。此病易与年龄相关性黄斑变性的新生血管相混淆,但二者在自然病程、预后、眼底血管造影等方面有显著差异。     

光相干断层扫描血管成像在眼底疾病诊断研究中的应用

光相干断层扫描血管成像(OCTA)通过对同一体素多次扫描信号间的差异进行处理,得到视网膜与脉络膜血流信息.OCTA因其无创、三维显示、分辨率高等优点,可用于眼底疾病的检查.OCTA能发现眼底疾病的血流改变,可以清晰显示正常眼底与年龄相关性黄斑变性、糖尿病视网膜病变、视网膜血管阻塞等疾病的视网膜与脉络膜毛细血管血流.本文就OCTA的基本原理及其在正常眼、年龄相关性黄斑变性与脉络膜新生血管、糖尿病视网膜病变、特发性黄斑中心凹旁毛细血管扩张症2型、视网膜血管阻塞、中心性浆液性脉络膜视网膜病变、息肉样脉络膜血管病变等眼底疾病诊断中的应用进行综述.     

特发性息肉样脉络膜血管病变一例报告

目的：报道1例特发性息肉样脉络膜血管病变的眼底荧光血管造影与吲哚青绿血管造影的临床特点。方法：常规眼科检查、眼底照相、荧光血管造影、吲哚青绿血管造影分析以及文献复习。结果：特发性息肉样脉络膜血管病变患者缺乏典型的玻璃疣,但可在视乳头与黄斑间出现大量泥沙样黄色渗出,眼底荧光血管造影中没有老年性黄斑变性样的新生血管,吲哚青绿血管造影中可见典型的息肉样脉络膜血管扩张,可单眼发病。结论：特发性息肉样脉络膜血管病变在临床表现以及眼底血管造影方面均有特征性改变。区分特发性息肉样脉络膜血管病变与老年性黄斑变性在疾病的视力预后、转归以及治疗处理上都有实际的临床意义。     

脉络膜厚度研究进展

临床应用的光相干断层扫描(OCT)改变了眼科临床诊疗方法.随着新技术的进展,OCT能够获得一个真实、非侵入性眼后段“光学切片”.随着OCT图像处理软件的改进,可以分析眼后段更精致的解剖结构,如脉络膜等.最近,高清晰选择性成像处理软件通过评估所有像素数据,减少噪音和构建最佳图像,通过图像增强软件补偿眼后段到视网膜色素上皮(RPE)细胞之间降低的信号强度,从而可见脉络膜与巩膜的分界线.因此,目前应用OCT能准确测量脉络膜厚度.脉络膜厚度受诸多因素影响,如体位、年龄、眼压、眼轴长度、屈光不正和收缩压等.脉络膜是眼部血液供给的重要组成部分,在诸多视网膜疾病的病理生理过程中起重要作用,如糖尿病视网膜病变(DR)、近视性黄斑病变、年龄相关性黄斑变性(AMD)、视网膜色素变性、正常眼压性青光眼(NTG)、高度近视、特发性黄斑裂孔等疾病中脉络膜变薄;中心性浆液性脉络膜视网膜病变(CSC)、息肉状脉络膜血管病变(PCV)、Vogt-小柳原田病(VKH)、开角型及闭角型青光眼、视网膜中央静脉阻塞(CRVO)、多发性一过性白点综合征等疾病中脉络膜增厚.本文就脉络膜厚度自身特点、脉络膜厚度的影响因素以及眼科疾病中脉络膜厚度变化进行综述.     

脉络膜厚度在青光眼发生发展中的作用研究进展

由于青光眼性视神经病变与供应视神经的血流异常有关,而视乳头筛板前区的血液供应主要来自视乳头周边的脉络膜血管分支,因此,青光眼和脉络膜血流之间的关系一直都备受关注。此外,在青光眼发病机制方面,脉络膜膨胀增厚也被认为是诱发急性闭角型青光眼的原因之一。随着频域OCT（SD-OCT）深度增强成像（EDI）技术应用,临床上已能在活体状态下较为准确地测量人体眼球的脉络膜厚度。笔者对SD-OCT深度增强成像技术所获得的青光眼患者脉络膜厚度方面的研究做一综述,并进一步探讨脉络膜在青光眼发生、发展中的作用。     

特发性息肉样脉络膜血管病变

特发性息肉样脉络膜血管病变是近10多年来提出的一种疾病，病因不明，病变位于脉络膜血管层，有不同粗细的分支血管的血管网，分支血管终端伸入浆液性或出血性脱离的色素上皮和神经上皮之间，并扩张成动脉瘤样或息肉样。此病易与年龄相关性黄斑变性的新生血管相混淆，但二在自然病程、预后、眼底血管造影等方面有显差异。     

OCT在检测糖尿病患者脉络膜厚度研究中的进展

脉络膜为外层视网膜提供氧和营养,维持光感受器细胞的代谢活性,其血管系统的正常结构与功能对于视网膜显得尤为重要。所以观察脉络膜形态对于跟踪糖尿病患者的病理变化较有意义。随着高分辨率光学相干断层扫描(optical coherence tomography,OCT)技术的应用,频域光学相干断层扫描( spectral-domain optical coherence tomography,SD-OCT)深度增强成像技术( enhanced depth imaging-technique,EDI)可定量测量脉络膜厚度,为诊断及治疗糖尿病视网膜病变提供了新的思路。在此,我们对OCT在检测糖尿病患者脉络膜厚度中的研究进展进行综述。     

Strabisme Alternant - Etude clinique - traitement

The author defines motor and sensory alternation: the term alternation should not be used in isolation, it should always be accompanied by the name of the parameter concerned. Sensory alternation is always found together with motor alternation but the reverse is not true.The examining criteria for a diagnosis of sensory alternation are given, sensory alternation must not be confused with alternating inhibition. Working from clinical observations of cases of motor alternating strabismus, the author selects 2 types of binocular sensory relations which allow one to differentiate between:- cases of primary alternating strabismus- cases of secondary alternating strabismusThese forms will develop in different ways; in both cases a cure is possible providing that the right treatment is prescribed and once prescribed carefully followed, etc. It is always a case of serious forms of strabismus whose developmental period is spread over several years.According to the authors, the frequency of cases of true primary strabismus is from 1–3%, the frequency of cases of secondary alternating strabismus varies according to the type of therapy practised on cases of monocular strabismus with amblyopia. These latter will become cases of alternating strabismus under the influence of certain types of therapy carried out over several years (penalization, rocking, alternated occlusion, etc...).Experimental data on kittens confirm clinical data; kittens placed in abnormal environments during the sensitive period will show modification in the distribution of cortical cells and the absence of binocular cells (either because the excitation of the two eyes was not simultaneous, or not identical: artificial strabismus, occlusion, opaque glasses). This disturbances become irreversible after a certain period of exposure (a function of age, length of exposure, etc...).It is thus necessary to bear in mind: 1) the iatrogenic risks of certain orthoptic treatments, 2) the necessity for a binocular form of treatment as soon as possible, as once a certain stage is passed, cortical plasticity diminishes and the elaboration of normal binocular relations becomes impossible.

---

     

Effects of Adenosine Agonists on Intraocular Pressure and Aqueous Humor Dynamics in Cynomolgus Monkeys

The effects of single or multiple topical doses of the relatively selective A₁adenosine receptor agonists (R)-phenylisopropyladenosine (R-PIA) and N⁶-cyclohexyladenosine (CHA) on intraocular pressure (IOP), aqueous humor flow (AHF) and outflow facility were investigated in ocular normotensive cynomolgus monkeys. IOP and AHF were determined, under ketamine anesthesia, by Goldmann applanation tonometry and fluorophotometry, respectively. Total outflow facility was determined by anterior chamber perfusion under pentobarbital anesthesia. A single unilateral topical application of R-PIA (20–250 μg) or CHA (20–500 μg) produced ocular hypertension (maximum rise=4.9 or 3.5 mmHg) within 30 min, followed by ocular hypotension (maximum fall=2.1 or 3.6 mmHg) from 2–6 hr. The relatively selective adenosine A₂antagonist 3,7-dimethyl-1-propargylxanthine (DMPX, 320 μg) inhibited the early hypertension, without influencing the hypotension. Neither 100 μg R-PIA nor 500 μg CHA clearly altered AHF. Total outflow facility was increased by 71% 3 hr after 100 μg R-PIA. In conclusion, the early ocular hypertension produced by topical adenosine agonists in cynomolgus monkeys is associated with the activation of adenosine A₂receptors, while the subsequent hypotension appears to be mediated by adenosine A₁receptors and results primarily from increased outflow facility.