糖尿病黄斑水肿患者病变程度与脉络膜厚度的关系

目的　利用频域光学相干断层扫描深度增强（enhanced depth imaging spectral domain optical coherence tomography，EDI SD-OCT）观察糖尿病黄斑水肿（diabetic macular edema，DME）患者脉络膜厚度（choroidal thickness，CT）的变化及结构特点，探讨DME病变程度与CT的关系。方法　纳入2型糖尿病患者共123例204眼，其中69眼诊断为DME（DME组），135眼无黄斑水肿为对照组。DME眼依据OCT形态学特点进一步分为视网膜弥漫性增厚（diffuse retinal thickness，DRT）型（34眼）、黄斑囊样水肿（cystoid macular edema，CME）型（19眼）和浆液性视网膜脱离（serous retinal detachment，SRD）型（16眼），利用EDI-OCT分别测量黄斑中心凹下CT和以黄斑为中心上、下、鼻、颞500 μm、1000 μm、1500 μm、2000 μm处CT。结果　DME组黄斑中心凹下CT为（326.72±90.15）μm，对照组为（320.17±106.46）μm，两组之间无统计学差异，但黄斑中心凹下CT与视网膜厚度间具有明显正相关关系（r=0.270，P=0.025）。DME亚型CT分别为:DRT型（303.94±81.47）μm、CME型（304.42±73.98）μm和SRD型（401.63±88.80）μm，SRD型CT明显高于其他亚型（P<0.05），此外，SRD型的周边CT同样呈现均匀一致的增厚；鼻侧CT从500 μm至2000 μm呈距离敏感性降低（P<0.05），但SRD型鼻侧CT降低幅度明显变缓（P=0.195）。结论　SRD型黄斑水肿患者CT在中心凹下及周边部均显著增厚，CT与DME病变程度之间有一定相关性。     

SD-OCT对原发性视网膜色素变性并发白内障患者行超声乳化联合人工晶状体植入术后视力预后的评估作用

目的　分析原发性视网膜色素变性（retinitis pigmentosa,RP）患者并发白内障行超声乳化联合人工晶状体植入术后视力的影响因素并探讨频域光学相干断层扫描（spectral domain optical coherence tomography,SD-OCT）在评估视力预后中的作用。方法　回顾性系列病例研究。收集RP并发白内障患者38例（58眼）,均行白内障手术治疗。根据SD-OCT下黄斑区椭圆体带的形态将患者分为3组,A组:黄斑区椭圆体带缺失（19眼）,B组:黄斑区椭圆体带可见但不连续（18眼）,C组:黄斑区椭圆体带完整（21眼）。比较所有患者手术前后最佳矫正视力（best corrected visual acuity,BCVA)、组内手术前后BCVA和组间手术前后BCVA;利用Pearson相关分析,分析SD-OCT检测指标的临床意义;并进一步对术后BCVA与黄斑中心凹厚度之间关系进行分析。结果　逐步回归分析结果表明,术前BCVA和黄斑区椭圆体带长度是影响术后视力的主要因素。手术前后BCVA之间、术后BCVA与黄斑区椭圆体带长度之间均呈直线相关（r=0.855、-0.622,均为P<0.01）。A组、B组和C组术前BCVA分别为（2.41±1.05）logMAR、（1.17±0.64）logMAR和（0.83±0.59）logMAR,术后第1天BCVA分别为（1.16±0.90）logMAR、（0.52±0.27）logMAR和（0.21±0.19）logMAR。各组患眼术后第1天BCVA均好于其术前视力（t=5.246、4.632、6.198,均为P<0.01）。3组患眼术后第1天BCVA比较,差异有统计学意义（F=32.760,P<0.01）。A组、B组和C组黄斑区椭圆体带长度分别为（0.00±0.00）mm、（1.16±0.57）mm和（4.04±1.26）mm,黄斑中心凹厚度分别为（100.84±45.49）μm、（203.44±33.33）μm和（248.19±37.79）μm。术后BCVA与黄斑中心凹厚度之间呈直线正相关（r=-0.754,P<0.01）。结论　白内障超声乳化吸出联合人工晶状体植入术治疗RP并发白内障可有效改善视功能。术前视力差、黄斑区椭圆体带结构的破坏以及黄斑中心凹厚度变薄是患者手术后视力不良的指征,SD-OCT对评估视力预后具有一定临床意义。     

频域-OCT在观察高眼压症视网膜神经纤维层及神经节细胞复合体中的应用

使用频域相干光断层扫描（ SD-OCT）观察高眼压症患者视盘形态学参数、视网膜神经纤维层（RNFL）及黄斑区神经节细胞复合体（GCC）的表现。方法选取52例（96只眼）高眼压患者,按照眼压高低分为两组,与20例（40只眼）正常人进行SD-OCT检查,测量视盘形态学参数、整体平均RNFL厚度（RNFL-Avg）、上方平均RNFL厚度（RNFL-Sup）、下方平均RNFL厚度（RNFL-Inf）、整体平均GCC的厚度（GCC-Avg）、上方平均GCC厚度（ GCC-Sup）、下方平均GCC厚度（ GCC-Inf）,比较两组高眼压症患者与正常对照组之间的差异,并分析高眼压症组RNFL与GCC的相关性。结果两组高眼压症患者与正常对照组比较,视盘各形态学参数（ P ＞0．05）、RNFL-Avg（ P ＝0．9017）、RNFL-Sup（ P ＝0．9659）、 RNFL-Inf（ P ＝0．7465）、 GCC-Avg（ P ＝0．3498）、GCC-Sup（ P ＝0.4203）、GCC-Inf（ P ＝0．3071）均无显著的统计学差异。而RNFL与GCC在整体、上方及下方的厚度均呈明显的正相关（ r ＝0．5631 P ＝0．001;r ＝0．5122 P ＝0．005;r ＝0．5459 P ＝0．002）。结论 SD-OCT是一种比较敏感的能够观察到视网膜结构改变的检查方法,对青光眼的早期诊断具有重要的作用。高眼压症患者在眼压明显高于正常的情况下,并无RNFL及GCC的改变,对于高眼压症应该强调严格随诊。     

眼缺血综合征患者脉络膜厚度的分析

目的 应用频域光学相干断层扫描仪(SD-OCT)测量眼缺血综合征(OIS)患者黄斑中心凹下脉络膜厚度(SFCT),观察OIS患者SFCT的特征,探索早期评估OIS的指标。 方法 为回顾性病例对照研究,共纳入2017年1月至2020年1月在北京市垂杨柳医院就诊患者48例(48眼),以是否确诊OIS将患者分为OIS组24例(24眼),对照组24例(24眼)。采集患者基线资料如年龄、性别、体质量指数(BMI)、糖尿病病史、高血压病史、高脂血症病史,应用SD-OCT的EDI模式测量SFCT,比较两组间的基线资料和SFCT的差异。 结果 OIS组和对照组患者在年龄、性别、BMI、糖尿病患病率、高血压患病率、高脂血症患病率方面相比,差异均无统计学意义(均P>0.05)。OIS组的平均SFCT为(204.83±27.34)μm,对照组的平均SFCT为(226.58±33.49)μm,两组的SFCT相比差异有统计学意义(t=2.464, P=0.018)。 结论 OIS患者的SFCT明显变薄,SFCT可作为早期评估OIS的指标。     

Photoreceptor cells as a source of fundus autofluorescence in recessive Stargardt disease

Bisretinoid fluorophores form in photoreceptor outer segments from nonenzymatic reactions of vitamin A aldehyde. The short-wavelength autofluorescence (SW-AF) of fundus flecks in recessive Stargardt disease (STGD1) suggests a connection to these fluorophores. Through multimodal imaging, we sought to elucidate this link. Flecks observed in SW-AF images often colocalized with foci exhibiting reduced or absent near-infrared autofluorescence signal, the source of which is melanin in retinal pigment epithelial (RPE) cells. With serial imaging, changes in near-infrared autofluorescence (NIR-AF) preceded the onset of fleck hyperautofluorescence in SW-AF images and fleck profiles in NIR-AF images tended to be larger. Flecks in SW-AF and NIR-AF images also corresponded to hyperreflective lesions traversing photoreceptor-attributable bands in horizontal SD-OCT scans. The hyperreflective lesions interrupted adjacent OCT reflectivity bands and were associated with thinning of the outer nuclear layer. These SD-OCT findings are attributable to photoreceptor cell degeneration. Progressive increases and decreases in the SW-AF intensity of flecks were evident in color-coded quantitative fundus autofluorescence maps. In some cases, flecks appeared to spread radially from the fovea to approximately 8° of eccentricity, beyond which a circumferential spread characterized the distribution. Since the NIR-AF signal is derived from melanin and loss of this autofluorescence is indicative of RPE atrophy, the SW-AF of flecks cannot be accounted for by bisretinoid lipofuscin in RPE. Instead, we suggest that the bisretinoid serving as the source of the SW-AF signal, resides in photoreceptors, the cell that is also the site of bisretinoid synthesis.     

Spatial correlation of mouse photoreceptor-RPE thickness between SD-OCT and histology

Spectral Domain Optical Coherence Tomography (SD-OCT) applied to the mouse retina has been limited due to inherent movement artifacts and lack of resolution. Recently, SD-OCT scans from a commercially available imaging system have yielded retinal thickness values comparable to histology. However, these measurements are based on single point analysis of images. Here we report that using the Spectralis HRA + OCT Spectral Domain OCT and Fluorescein Angiography system (Heidelberg Engineering, Heidelberg, Germany), retinal thickness of linear expanses from SD-OCT data can be accurately assessed. This is possible by the development of a Spectralis-compatible ImageJ plug-in that imports 8-bit SLO and 32-bit OCT B-scan images, retaining scale and segmentation data and enabling analysis and 3D reconstruction. Moreover, mouse retinal layer thickness values obtained with this plug-in exhibit a high correlation to thickness measurements from histology of the same retinas. Thus, use of this ImageJ plug-in results in reliable quantification of long retinal expanses from in vivo SD-OCT images.