光学相干断层扫描技术在眼前节结构应用的新进展

光学相干断层扫描技术（OCT）是一种利用光的干涉原理来成像眼部结构的方法,最初用于眼后节的测量和检查,但随着OCT技术的进展,目前已广泛用于眼前节各组织的测量和检查.眼前节光学相干断层扫描技术（AS-OCT）可将角膜、前房、瞳孔、虹膜等眼前节组织结构显示于一张图像上,并可用于准分子激光角膜原位磨镶术术后角膜前后表面情况和角膜曲率的测定,青光眼患者房角、虹膜、睫状体的观察,抗青光眼术后功能性滤过泡的动态变化以及眼外伤患者的眼前节组织结构变化等.AS-OCT检测具有非接触、分辨率高、检测快捷、可定量分析等特点,因此是眼前节组织的检测的有力工具.就AS-OCT技术在眼科的临床应用、优缺点及展望进行综述.     

Anterior Segment Optical Coherence Tomography

Optical coherence tomography (OCT) is a non-contact optical signal acquisition and processing device that provides magnified, high resolution cross-sectional images of ocular tissues. Development of anterior segment OCT (AS-OCT) offers the benefits of fine resolution and noninvasive examination to investigation of anterior segment anatomy to the depth of the iris plane. This imaging device has been utilized for investigation into a myriad of corneal and anterior segment disease. Recent technological advances toward three-dimensional visualization broaden the scope of AS-OCT in ophthalmologic evaluation. The AS-OCT is a valuable imaging tool whose use in research and clinical practice will continue to expand our knowledge and management of various ophthalmic conditions.     

Anterior segment optical coherence tomography

Optical coherence tomography (OCT) is a non-contact optical signal acquisition and processing device that provides magnified, high resolution cross-sectional images of ocular tissues. Development of anterior segment OCT (AS-OCT) offers the benefits of fine resolution and noninvasive examination to investigation of anterior segment anatomy to the depth of the iris plane. This imaging device has been utilized for investigation into a myriad of corneal and anterior segment disease. Recent technological advances toward three-dimensional visualization broaden the scope of AS-OCT in ophthalmologic evaluation. The AS-OCT is a valuable imaging tool whose use in research and clinical practice will continue to expand our knowledge and management of various ophthalmic conditions.     

光相干断层扫描技术在眼表鳞状上皮瘤诊疗中的应用及展望

眼前节光相干断层扫描技术(AS-OCT)作为一种无创性检查手段,具有检测肿瘤性上皮病变的巨大潜力。依据AS-OCT上的特征性表现,可在多种眼表疾病中检测出眼表鳞状上皮瘤(OSSN)的存在,其诊断效果堪比病理组织活检。随着技术的发展,AS-OCT成像模式已从时域OCT发展到具有更高外显率和分辨率的频域OCT,其呈现的高质...     

Pentacam与前节OCT测量有晶状体眼后房型人工晶状体植入术后拱高的比较

目的对有晶状体眼后房型人工晶状体（PPC-ICL）植入术后患者应用三维眼前节全景分析仪（Pentacam）与前节光学相干断层扫描仪（AS-OCT）测量拱高及其他眼前节参数,分析2种仪器的差异性和一致性。方法横断面研究。连续选取50例（100眼）PPC-ICL植入术术后复查患者,分别应用Pentacam和前节OCT测量眼前节参数。采用配对样本t检验及Bland-Altman图法对二者差异性和一致性进行统计学分析。结果Pentacam测得拱高值为（353.8±124.0）µm,前节OCT测得拱高值为（536.2±150.8）µm,两者差异有统计学意义（t=27.92,P＜0.05）,两者呈高度正相关性（r=0.905,P＜0.05）,Pentacam测得拱高比前节OCT测得拱高低（182.4±65.3）µm,其差值95%一致性区间为54.3～310.5 µm。结论Pentacam与前节OCT均能为我们提供拱高值,Pentacam测量值显著低于前节OCT测量值,在临床工作中应该综合分析。     

超高分辨率光学相干断层扫描在眼前节的应用进展

作为一项非接触、无创的组织结构成像技术,光学相干断层扫描（optical coherence tomography,OCT）系统可对眼组织高分辨率成像。最初应用于眼后节组织结构成像,随后逐渐应用于眼前节。眼前节OCT技术的发展确保眼前节组织结构精准成像。近来提出的超高分辨率OCT（ultrahigh-resolution OCT,UHR-OCT）技术,实现了对眼前节各层次组织结构超高分辨成像,并成功应用于眼前节及眼表疾病的诊治。如定量测量干眼症患者泪膜厚度值,鉴别诊断眼表鳞状上皮瘤样增生性病变,监测各类角膜炎、圆锥角膜、角膜外伤等角膜疾病的病理生理变化趋势。同时,UHR-OCT亦可协助临床工作者制定合理的眼前节手术方案,如角膜移植术,并追踪观察术后角膜组织愈合等形态学变化情况。此外,该技术加深了对眼前节组织结构生理及病理生理形态学的了解。本文主要对UHR-OCT的技术原理及在眼前节应用进展等进行综述。     

Detection of occludable angle with anterior segment optical coherence tomography and Pentacam as non-contact screening methods

International Ophthalmology - To evaluate diagnostic capacity for occludable anterior chamber angle detection with anterior segment optical coherence tomography (AS-OCT) and Pentacam. Observational...     

Anterior segment optical coherence tomography documentation of a case of topiramate induced acute angle closure

We present a case report of a 31-year-old female patient who presented to us with a 1 day history of acute bilateral eye pain, blurred vision and headache. She was found to have a myopic shift, raised intraocular pressure (IOP) and shallow anterior chambers in both eyes. She had been commenced on oral topiramate 1 week previously. A number of investigations, including anterior segment optical coherence tomography (AS-OCT) were done and a diagnosis of topiramate induced bilateral acute angle closure (TiAAC) was made. Topiramate was discontinued and she was managed with topical and oral antiglaucoma medications, topical steroids and cyclopegics. Her symptoms subsided dramatically at the next follow-up. The AS-OCT documentation revealed lucidly the improvement in her anterior chamber depth and anterior chamber angle parameters. Her IOP decreased, her myopic shift showed reversal and her AS-OCT findings revealed gross improvement in all the parameters angle opening distance, trabecular iris space area and scleral spur angle. This case report clearly shows with AS OCT documentation the changes which occur in the anterior segment in a case of TiAAC.     

Comparative study of anterior segment measurement with Pentacam and anterior segment optical coherence tomography

Objective: To evaluate the repeatability of central corneal thickness (CCT), anterior chamber volume (ACV), and central anterior chamber depth (CACD) measurements obtained using a Pentacam rotating Scheimpflug camera, and to examine their agreement with measurements obtained using an anterior segment optical coherence tomography (AS-OCT) imaging system.Design: Observational cross-sectional study.Participants: Fifty eyes from 50 healthy subjects were recruited.Methods: CCT, CACD, and ACV were measured. Subjects were re-examined twice within a week of the first measurements. Intrasession and intersession within-subject SD (S_w), precision (1.96 × S_w), coefficient of variation (CV_w: 100 × S_w/ overall mean), and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability and reproducibility. Bland-Altman plots were used to assess agreements between Pentacam and AS-OCT measurements.Results: For intrasession repeatability, CVwand ICC values were 0.78 and 0.98 for CCT, 0.92 and 0.99 for CACD, and 3.52 and 0.98 for ACV, respectively. For intersession repeatability, CV_w and ICC values were 1.19 and 0.96 for CCT, 1.25 and 0.99 for CACD, and 3.96 and 0.96 for ACV, respectively. The AS-OCT CCT measurement (519.23 [SD 34.37] μm) was 18.53 μm less than the Pentacam measurement (537.76 [SD 31.84] μm). The Pentacam CACD measurement (3.03 [SD 0.32] mm) was 0.08 less than the AS-OCT measurement (3.11 [SD 0.31] mm). The Pentacam ACV measurement (165.56 [SD 34.86] μL) was 14.21 μL less than the AS-OCT measurement (179.77 [SD 34.57] μL).Conclusions: Although the Pentacam measurements of the anterior segment parameters were reliable, their agreement with the AS-OCT measurements was not sufficient.     

眼前节相干光断层扫描仪与Orbscan Ⅱ及超声法眼前节生物测量对比研究

目的 比较眼前节相干光断层扫描仪(AS-OCT)与Orbscan Ⅱ以及超声法眼的节生物测量结果,为临床应用提供参考:方法对33例(66只眼)近视眼患者分别行AS-OCT,Orbscan Ⅱ以及A型超声测量仪(DGH550和DGH4000)进行眼前节生物测量,获取角膜中央厚度(CCT),前房深度(ACD),角膜直径,瞳孔直径以及前房角度数,进行对比分析.结果 AS-OCT,Orbscan Ⅱ以及超声法测量CCT分别为(532.32±35.26)μm.(538.45±38.31)μm,(555.82±37.63)μm,两两比较各组差异均有统计学意义(P<0.01).相关性分析显示三种方法中两两间均呈正相关,相关系数r=0.92、0.91、0.95;ACD分别为(3.19±0.21)mm,(3.08±0.24)mm,和(3.27±0.23)mm,两两间差异也均有统计学意义(P<0.01). OCT法测量瞳孔直径为(5.5±0.93)mm,Orbscan法测量结果为(4.5±0.75)mm,二者相差(-1.00±0.68)mm.差异有统计学意义(t=11.95,P=0.000),95%置信区间(0.84,1.17). OCT测量房角度数均大于Orbscan测量结果,在180度二者相差1.58度,差异无统计学意义(t=1.58,P=0.119),在0度相差2.89度,差异有统计学意义(t=2.89,P=0.005).结论 AS-OCT测量角膜中央厚度较Orbscan Ⅱ以及超声法测量结果薄,前房深度较Orbscan结果深,更接近于超声测量结果.房角角度测量结果与Orbscan结果近似,且能直观显示房角结构;眼前节OCT快速,非接触,在眼前节生物测量有广泛的应用前景.     

眼前节OCT在圆锥角膜急性角膜水肿中的运用

目的：探讨圆锥角膜急性水肿的眼前节OCT影像学特征,分析角膜水肿发生发展的原因。方法：收集8例急性角膜水肿的圆锥角膜患者,行常规眼部检查及眼前节OCT检查。结果：角膜基质层内形成一裂隙与前房相沟通。角膜基质层的厚度在发生裂隙的部位十分菲薄,甚至穿孔,发生虹膜组织嵌顿。结论：角膜基质层裂隙的形成可能是导致急性角膜水肿的一个重要原因,裂隙还可能导致持续的水肿及后弹力层的延迟愈合,严重者甚至造成角膜穿孔。     

Early changes in corneal edema following torsional phacoemulsification using anterior segment optical coherence tomography and Scheimpflug photography

Purpose  

To assess corneal edema after torsional phacoemulsification using anterior segment optical coherence tomography (AS-OCT) and Scheimpflug photography (Pentacam).     

To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOLMaster 700, Cirrus anterior segment optical coherence tomography and Tomey specular microscopy in normal healthy eyes

Purpose:To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOL Master 700, Cirrus Anterior segment optical coherence tomography and Tomey Specular microscopy in normal healthy eyes.Methods:Two hundred and six eyes of healthy subjects were included in the study. Each subject was assessed by four different methods of measuring central corneal thickness using Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy by a single examiner.Results:The mean CCT [± standard deviation (SD)] for Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy were Pentacam (Oculus), AS-OCT (Cirrus), IOL Master 700 and Specular microscopy (Tomey) were 523.75 (±27.75), 525.29 (±28.81),517.13 (±28.43) and 512.82 (±27.60) μm, respectively. All the means were significantly different from one another (P < 0.000). The differences between pairs of mean central corneal thickness (CCT) for Pentacam and IOL Master, Pentacam and anterior segment- optical coherence tomography (AS-OCT), and Pentacam and Specular microscopy are statistically significant. Bland–Altman plots showed that pentacam and IOL Master 700 have the closest agreement, followed by AS-OCT. Specular microscopy was found to have the poorest agreement with Pentacam.Conclusion:We found that CCT measurements of Pentacam did not correlate with measurements of IOL Master, or AS-OCT or Specular microscopy. In clinical practice, the devices analyzed should not be used interchangeably due to low agreement regarding CCT values.     

超声乳化白内障摘出术对慢性原发性闭角型青光眼患者眼前段参数的影响

目的观察超声乳化白内障摘出术对慢性原发性闭角型青光眼(chronic primary angle-closure glaucoma,CPACG)患者眼前段参数的影响。方法 收集2010年7月至12月于中山大学附属中山医院眼科就诊的CPACG患者41例(41眼),常规行超声乳化白内障摘出联合人工晶状体植入术。术前和术后3个月使用Pentacam和眼前段光学相干断层扫描(anterior segmentocular coherence tomography,AS-OCT)测量仪测量眼前段参数,包括中央前房深度、周边前房深度、前房容积、前房角和瞳孔直径等。结果 所有患者眼压由术前(33.15±5.10)mmHg(1kPa=7.5mmHg)降至术后3个月(16.32±3.36)mmHg,中央前房深度由(1.78±0.20)mm增至(3.40±0.37)mm,周边前房深度由(0.82±0.11)mm加深至(1.81±0.20)mm,前房容积由(74.20±9.76)mm3增加至(149.78±16.87)mm3;下方前房角由23.97°±3.43°加宽至43.29°±3.83°,鼻侧由22.85°±2.99°加宽至42.14°±4.60°,上方由21.54°±2.99°加宽至39.69°±3.46°,颞侧由22.81°±2.81°加宽至41.07°±3.77°,术前、术后各象限前房角比较差异均有统计学意义(均为P<0.05)。瞳孔直径由术前(3.07±1.29)mm减至术后的(3.02±1.19)mm,差异无统计学意义(t=1.147,P=0.258)。结论 Pentacam和AS-OCT对眼前段结构的观察具有重要的临床价值,超声乳化白内障摘出术可改善CPACG患者眼前段的狭窄。     

超声生物显微镜在眼前段微小异物诊断的应用

目的探讨超声生物显微镜（UBM）在眼前段微小异物诊断中的应用。方法应用UBM对7例眼前段异物诊断和定位并经手术摘出证实。结果7例异物均经UBM定位后手术顺利取出。结论相对于其他影像学检查，UBM在眼前段异物诊断和定位中具有明显的优越性。     

前节相干光断层扫描技术在角膜外伤中的应用研究

目的评估前节相干光断层扫描技术（AS-OCT）在角膜外伤诊疗中的应用价值。方法回顾性分析85例（91只眼）各类角膜外伤：穿通伤56只眼,钝挫伤18只眼,角膜异物10只眼,化学伤7只眼。所有患者在诊疗过程中除常规裂隙灯显微镜等检查外,均以AS-OCT观察了角膜形态结构,部分患者进行了角膜厚度测量。结果所有病例均获得清晰AS-OCT角膜图像,8只眼角膜穿通伤病例清创缝合术后患眼发现严重角膜伤口内口对合不佳,3只眼LASIK术后眼球钝挫伤发现角膜层间积液,对于透明/半透明角膜异物病例,AS-OCT可显示异物在角膜内具体位置。但对于金属异物,在AS-OCT检查所获图像中异物后的部分呈现为无反射区,故而无法判断异物深度。AS-OCT可清晰显示急性期角膜化学伤患者角膜水肿情况并可进行厚度测量。1只眼因陈旧性化学伤导致的角膜白斑,裂隙灯显微镜下无法窥见眼内结构,AS-OCT显示前房、虹膜结构基本正常。结论 AS-OCT可清晰显示外伤后角膜的形态结构,对于角膜外伤的诊断和疗效评估具有很好的应用价值。     

Anterior segment optical coherence tomography: its application in clinical practice and experimental models of disease

Optical coherence tomography (OCT) provides non‐invasive, high‐resolution in vivo imaging of the ocular surface and anterior segment. Over the years, it has become an essential tool for evaluating the anterior segment of the eye to monitor ocular development and ocular pathologies in both the clinical and research fields of ophthalmology and optometry. In this review, the clinical applications relating to the use of anterior segment OCT for imaging and quantifying normal and pathological features of the ocular surface, cornea, anterior chamber, and aqueous outflow system are summarised in a range of human ocular diseases. Applications of anterior segment OCT technology that have improved imaging and quantitation of ocular inflammation in experimental animal models of ocular diseases, such as anterior uveitis, microbial keratitis and glaucoma, are also described. The capacity to longitudinally evaluate anterior segment anatomical changes during development, and inflammation facilitates the understanding of the dynamics of tissue responses, and further enhances the intra‐operative in vivo imaging during procedures, such as corneal transplantation and drug delivery. Future developments including in vivo ultrahigh‐resolution anterior segment OCT, automated analyses of anterior segment OCT images and functional extensions of the technique, may revolutionise the clinical evaluation of anterior segment, corneal and ocular surface diseases.     

Pentacam与AS-OCT测量眼前节生物参数的比较

目的：在两组人群中比较Pentacam眼前节分析仪与眼前节光相干断层扫描(AS-OCT)测量的角膜曲率及角膜散光、中央角膜厚度和前房深度的差异性、相关性及一致性,为临床使用提供参考。

方法：前瞻性临床研究。纳入青年近视术前检查者64例124眼、年龄相关性白内障患者61例85眼,先后使用Pentacam和AS-OCT进行测量,获得眼前节生物参数。在两组人群中采用配对样本t检验分别对两种仪器测量结果的差异性进行比较,所得数据的相关性采用 Pearson相关性分析,测量结果的一致性采用 Bland-Altman 分析。

结果：近视组两种仪器测得的陡峭角膜曲率(Ks)、平坦角膜曲率(Kf)、平均角膜曲率(Km)有显著差异(P<0.001),而白内障组测得的Ks、Kf、Km无差异(P>0.05),两组人群两种仪器测量的J₀(散光参数)、平均角膜厚度(CCT)、前房深度(ACD)均有差异(P<0.05),测得J₄₅(散光参数)无差异(P>0.05)。两组人群中两种仪器测量的Ks、Kf、Km、J₀、J₄₅、CCT及ACD均具有线性相关(P<0.001)。近视组测量的Ks、Kf、Km的一致性良好,而白内障组测量的Ks、Kf、Km的一致性较差。

结论：Pentacam和AS-OCT测量散光参数、CCT及ACD时具有较好一致性,可互换使用,而测量Ks、Kf、Km时的一致性受年龄相关因素影响,优先考虑选择Pentacam。     

Anterior segment imaging in glaucoma: An updated review

Anterior segment imaging allows for an objective method of visualizing the anterior segment angle. Two of the most commonly used devices for anterior segment imaging include the anterior segment optical coherence tomography (AS-OCT) and the ultrasound biomicroscopy (UBM). AS-OCT technology has several types, including time-domain, swept-source, and spectral-domain-based configurations. We performed a literature search on PubMed for articles containing the text “anterior segment OCT,” “ultrasound biomicroscopy,” and “anterior segment imaging” since 2004, with some pertinent references before 2004 included for completeness. This review compares the advantages and disadvantages of AS-OCT and UBM, and summarizes the most recent literature regarding the importance of these devices in glaucoma diagnosis and management. These devices not only aid in visualization of the angle, but also have important postsurgical applications in bleb and tube imaging.     

Recent advances in optical coherence tomography for anterior segment imaging in small animals and their clinical implications

Anterior segment optical coherence tomography (AS-OCT) is a rapidly evolving area of OCT imaging, providing high-resolution and non-invasive volumetric imaging of the anterior segment. This review focuses on recent advances in AS-OCT imaging in small animals, which we categorize into ultrahigh-resolution, spectroscopic, magnetomotive, polarization-sensitive, and angiographic AS-OCTs. We summarize their technical foundations, review their applications to small animal imaging, and briefly discuss their current and future clinical applications.