黄芩苷对家兔视网膜炎性水肿厚度影响的研究

目的:研究黄芩苷对炎性视网膜水肿的影响。方法:建立炎性视网膜水肿的动物模型,用OCT测量黄芩苷对炎性视网膜水肿过程中视网膜厚度的影响。新西兰白兔15只(30个视网膜)随机分为5组,建立炎性视网膜水肿模型后,组1注射黄芩苷溶液(160mg/L,20mL/kg),2次/d;组2使用黄芩苷溶液(40mg/L,20mL/kg),2次/d;组3使用黄芩苷溶液(10mg/L,20mL/kg),2次/d;组4使用球后注射曲安奈德,给药剂量为20mg(0.5mL)。组5为对照组,被耳缘静脉注射等量BSS。分别在建模后1,2,4,6,10,14,21d用光学相干断层扫描(opitical coherence tomograph,OCT)测量视网膜的平均厚度。结果:与炎性对照组相比,黄芩苷治疗组视网膜厚度明显降低,两组差异具有统计学意义(P<0.01);黄芩苷组与激素组比较,48h内有差别,但差异不显著(t=5.85,4.3;0.001<P<0.01);2d后,两组差异性消失(t<2.447,P>0.05),从统计学角度看两者无差别。结论:黄芩苷能够有效抑制炎性视网膜细胞外水肿,并且与皮质激素具有相同的药效,并且无明显毒副作用。

两种非甾体抗炎药对白内障术后黄斑水肿影响的对比研究

目的比较0.1%溴芬酸钠水合物滴眼液和普拉洛芬滴眼液对白内障超声乳化术后黄斑水肿的影响。方法采用前瞻性临床随机对照试验。将行白内障超声乳化吸除联合人工晶状体植入术的年龄相关性白内障患者随机分为两组,每组118只眼。A组:术前2 d和术后4周应用0.1%溴芬酸钠水合物滴眼液,联合术后2周应用妥布霉素地塞米松滴眼液;B组:术前2 d和术后4周应用普拉洛芬滴眼液,联合术后2周应用妥布霉素地塞米松滴眼液。分别在术前2 d内,术后1 d、1、4、12周测定黄斑中心亚区域平均厚度(CSMT),并计算术后黄斑水肿发生率。结果术前、术后1 d、1周、12周A组与B组CSMT比较,差异均无统计学意义(P>0.05);术后4周A组CSMT为(251.57±6.814)μm,低于B组的(254.40±12.004)μm,差异有统计学意义(P<0.05);术后1 d、1、4、12个月试验组黄斑水肿发生率分别为0、0、0.85%、0.85%,对照组分别为0、0.85%、1.69%、1.69%,术后各时间点两组黄斑水肿发生率比较,差异均无统计学意义(P>0.05)。结论白内障超声乳化术前和术后应用0.1%溴芬酸钠水合物滴眼液或普拉洛芬滴眼液,术后黄斑水肿发生率均较低,前者比后者可能会更大程度地抑制术后黄斑中心亚区域增厚。

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

目的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)、RNFLAvg(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。

玻璃体切除联合内界膜翻转覆盖治疗特发性黄斑裂孔的临床疗效观察

目的应用玻璃体切除联合内界膜翻转覆盖法治疗特发性黄斑裂孔(IMH),观察术后黄斑裂孔解剖结构及视力的变化情况。方法选取临床确诊IMH患者31例(31只眼),其中男性8例(8只眼),女性23例(23只眼),患者年龄范围:42~82岁,平均(65.68±8.39)岁,行23G玻璃体切除联合内界膜翻转覆盖及注气术。于术后5 d,2周,1、3、6个月进行随访,所有患眼手术前后行最佳矫正视力(BCVA)、裂隙灯,眼底广角眼底照相,频域相干光断层扫描(SD-OCT)检查。观察手术后患者黄斑裂孔愈合率,手术前后BCVA变化情况,黄斑裂孔的愈合类型,翻转覆盖的内界膜与裂孔的位置关系,椭圆体区缺损直径的变化情况。结果术后黄斑裂孔愈合率为100%。手术前后BCVA有显著性差异(t=8.50,P<0.05),术后视力提高。30例裂孔呈"U"型愈合,1例裂孔呈"V"型愈合。29例内界膜瓣完全贴附于视网膜,2例内界膜未完全贴附视网膜并成桥样附着在裂孔正上方。术后椭圆体缺失直径逐渐减小。结论玻璃体切除联合内界膜瓣翻转覆盖术治疗IMH可以取得较高的解剖学复位率和裂孔愈合率,提高视力患者视力,是治疗IMH一种安全有效的手术方法。

Cervical inlet patch-optical coherence tomography imaging and clinical significance

AIM:To demonstrate the feasibility of optical coherence tomography(OCT)imaging in differentiating cervical inlet patch(CIP)from normal esophagus,Barrett'sesophagus(BE),normal stomach and duodenum. METHODS:This study was conducted at the Veterans Affairs Boston Healthcare System(VABHS).Patients undergoing standard esophagogastroduodenoscopy at VABHS,including one patient with CIP,one representative patient with BE and three representative normal subjects were included.White light video endoscopy was performed and endoscopic 3D-OCT images were obtained in each patient using a prototype OCT system.The OCT imaging probe passes through the working channel of the endoscope to enable simultaneous video endoscopy and 3D-OCT examination of the human gastrointestinal(GI)tract.Standard hematoxylin and eosin(H and E)histology was performed on biopsy or endoscopic mucosal resection specimens in order to compare and validate the 3D-OCT data. RESULTS:CIP was observed from a 68-year old male with gastroesophageal reflux disease.The CIP region appeared as a pink circular lesion in the upper esophagus under white light endoscopy.OCT imaging over the CIP region showed columnar epithelium structure,which clearly contrasted the squamous epithelium structure from adjacent normal esophagus.3D-OCT images obtained from other representative patients demonstrated distinctive patterns of the normal esophagus,BE,normal stomach,and normal duodenum bulb.Microstructures,such as squamous epithelium,lamina propria, muscularis mucosa,muscularis propria,esophageal glands,Barrett's glands,gastric mucosa,gastric glands, and intestinal mucosal villi were clearly observed with OCT and matched with H and E histology.These results demonstrated the feasibility of using OCT to evaluate GI tissue morphology in situ and in real-time. CONCLUSION:We demonstrate in situ evaluation of CIP microstructures using 3D-OCT,which may be a useful tool for future diagnosis and follow-up of patients with CIP.

Optical coherence tomography and Doppler optical coherence tomography in the gastrointestinal tract

Optical coherence tomography(OCT) is a noninvasive,high-resolution,high-potential imaging method that has recently been introduced into medical investigations.A growing number of studies have used this technique in the field of gastroenterology in order to assist classical analyses.Lately,3D-imaging and Doppler capabilities have been developed in different configurations,which make this type of investigation more attractive.This paper reviews the principles and characteristics of OCT and Doppler-OCT in connection with analyses of the detection of normal and pathological structures,and with the possibility to investigate angiogenesis in the gastrointestinal tract.

Spectral Domain Optical Coherence Tomography of Vogt-Koyanagi-Harada Disease: Novel Findings and New Insights into the Pathogenesis

Objective To provide novel spectral domain optical coherence tomography (SD OCT) findings of Vogt-Koyanagi-Harada (VKH) disease as well as new insights into the pathogenesis of this disease. Methods Detailed SD OCT and fluorescein angiography (FA) findings of 18 consecutive VKH patients (11 women and 7 men) from December 2007 to April 2009 who were in acute uveitic stage at presentation were reviewed. All the patients had been followed up for at least 6 months with reevaluation(s) of SD OCT performed in 10 patients. Results Intraretinal cysts were found to be located in various layers of the outer retina. In addition to the photoreceptor layer, they could also be found between the outer plexiform layer and the outer nuclear layer, or spanning the external limiting membrane. On FA, intraretinal cysts could be hypofluorescent, normofluorescent, or hyperfluorescent. Some intraretinal cysts had a characteristic FA pattern, in which a small round hypofluorescent area was surrounded by a ring of hyperfluorescence (donut-shaped dye pooling). Subretinal fibrinoid deposit appeared in acute uveitic stage in two severe VKH patients and seemed to develop from subretinal exudates and evolved into typical subretinal fibrosis. Gradual transfiguration/migration and progressive proliferation/pigmentation of the subretinal fibrinoid deposit/subretinal fibrosis was observed in one patient. Conclusions Intraretinal cysts could form in various layers of the outer retina and may result from extension of choroidal inflammation. Subretinal fibrosis may develop from subretinal exudates in VKH patients and may cause substantial visual impairment.

Intraretinal layer segmentation and parameter measurement in optic nerve head region through energy function of spatial-gradient continuity constraint

For the diagnosis of glaucoma,optical coherence tomography(OCT)is a noninvasive imaging technique for the assessment of retinal layers.To accurately segment intraretinal layers in an optic nerve head(ONH)region,we proposed an automatic method for the segmentation of three intraretinal layers in eye OCT scans centered on ONH.The internal limiting membrane,inner segment and outer segment,Bruch’s membrane surfaces under vascular shadows,and interaction of multiple high-reflectivity regions in the OCT image can be accurately segmented through this method.Then,we constructed a novel spatial-gradient continuity constraint,termed spatial-gradient continuity constraint,for the correction of discontinuity between adjacent image segmentation results.In our experiment,we randomly selected 20 B-scans,each annotated three retinal layers by experts.Signed distance errors of?0.80μm obtained through this method are lower than those obtained through the state-of-art method(?1.43μm).Meanwhile,the segmentation results can be used as bases for the diagnosis of glaucoma.

Parallel Spectral-Domain Optical Coherence Tomography for Non-Scattering Object Imaging

The parallel spectral-domain optical coherence tomography（PSDOCT） is described for highspeed optical coherence tomography（OCT） without lateral scanning. In this setup, the self-elimination of auto-correlation（AC） interference algorithm was used for eradicating the AC interference and ghost images. However, when performed in free space OCT, this algorithm still generated a weak DC component. The algorithm was improved by adding the background intensity part to compensate for the mutual interference between object and reference arms. The results demonstrate that the DC component can be eradicated. Compared with conventional QCT and complex Fourier-domain optical coherence to- mography, the advantages of PSDOCT with the improved algorithm in free space are that it has no moving parts to generate consecutive phase shift, the structure of the object can be reconstructed immediately and automatically, and the speed is approximately 16 times faster than those of the other two in the same case.

Optical molecular imaging for detection of Barrett's-associated neoplasia

Recent advancements in the endoscopic imaging of Barrett's esophagus can be used to probe a wide range of optical properties that are altered with neoplastic progression.This review summarizes relevant changes in optical properties as well as imaging approaches that measures those changes.Wide-field imaging approaches include narrow-band imaging that measures changes in light scattering and absorption,and autofluorescence imaging that measure changes in endogenous fluorophores.High-resolution imaging approaches include optical coherence tomography,endocytoscopy,confocal microendoscopy,and high-resolution microendoscopy.These technologies,some coupled with an appropriate contrast agent,can measure differences in glandular morphology,nuclear morphology,or vascular alterations associated with neoplasia.Advances in targeted contrast agents are further discussed.Studies that have explored these technologies are highlighted;as are the advantages and limitations of each.

Thrombosis of celiacomesenteric trunk:Report of a case

Here we present the case of a 79-year-old woman who complained of acute abdominal pain,vomiting and diarrhoea.Laboratory exams demonstrated a severe metabolic imbalance.Abdominal X-rays showed bowel overdistension and pneumatosis of the stomach wall.Abdominal tomography revealed infarction of the stomach,duodenum and small bowel due to thrombosis of the celiacomesenteric trunk.Exploratory laparotomy revealed ischemia of the liver,spleen infarction and necrosis of the gastro-intestinal tube(from the stomach up to the first third of the transverse colon).No further surgical procedures were performed.The patient died the following day.To our knowledge,this is the first reported case about severe gastro-intestinal ischemia due to thrombosis of the celiacomesenteric trunk,a rare anatomic variation of the gastrointestinal vascularisation.

Identification of the layered morphology of the esophageal wall by optical coherence tomography

AIM： To assess each layer of the optical coherence tomography （OCT） image of the esophageal wall with reference to the histological structure, METHODS： Resected specimens of fresh pig esophagus was used as a model for the esophageal wall. We injected cyanoacrylate adhesive into the specimens to create a marker, and scanned them using a miniature OCT probe. The localization of these markers was assessed in the OCT images. Then we compared the OCT-imaged morphology with the corresponding histological section, guided by the cyanoacrylate adhesive markers. We prepared a second set of experiments using nylon sutures as markers. RESULTS： The OCT image of the esophageal specimen has a clear five-layered morphology. First, it consisted of a relatively less reflective layer; second, a more reflective layer; third, a less reflective layer; fourth, a more reflective layer; and fifth, a less reflective layer. Comparing the OCT images with marked histological sections showed that the first layer corresponded to stratified squamous epithelium; the second to lamina propria; the third to muscularis mucosa; fourth, submucosa; and fifth, muscularis propria with deeper structures of the esophageal wa CONCLUSION： We demonstrated that the OCT image of the normal esophageal wall showed a five- layered morphology, which corresponds to histological esophageal wall components.

Central visual function and inner retinal structure in primary open-angle glaucoma

To investigate associations between central visual function and inner retinal structure in primary open-angle glaucoma(POAG). This study enrolled 78 POAG patients and 58 healthy controls. POAG was classified into early glaucoma and moderate to advanced glaucoma. The following tests were performed on all participants: isolated-check visual evoked potential(ic VEP) testing, 24-2 standard automated perimetry(SAP), and Cirrus optical coherence tomography(OCT) examinations. Signal-to-noise ratio(SNR) measures obtained from ic VEP responses to isolated checks presented at four depths of modulation(DOMs;8%, 14%, 22%, and 32%) were explored. Mean macular sensitivity(mMS) was assessed by calculating the mean sensitivities of central 12 SAP points. Ganglion cell layer+ inner plexiform layer thickness(GCL+IPLT) and peripapillary retinal nerve fiber layer thickness(pRNFLT) were measured by OCT scanning. For each group of subjects, linear relationships among the following measures were analyzed: SNR, mMS, GCL+IPLT, and pRNFLT. SNR, mMS, GCL+IPLT, and pRNFLT were all more significantly decreased in glaucoma than in controls(P<0.001). A significant positive association was found between SNR at 14% DOM and GCL+IPLT at the inferior sector in early glaucoma(r=0.465, P=0.004). In moderate to advanced glaucoma, significant correlations were found between SNR at 32% DOM and mean GCL+IPLT(r=0.364, P=0.023), superior GCL+IPLT(r=0.358, P=0.025), and mean p RNFLT(r=0.396, P=0.025). In addition, in moderate to advanced glaucoma, there were significant correlations between mMS and all relevant measures of retinal thickness(r=0.330–0.663, P< 0.010). In early glaucoma, significant correlations were found between mean mMS and minimum GCL+IPLT(r=0.373, P=0.023), and between inferior mMS and superior GCL+IPLT(r=0.470, P=0.003). Linear models provided a good explanation for the relationship between SNR and inner retinal thickness(IRT), whereas nonlinear models better explained the relationship between mMS and IRT. In early glaucoma, both SNR and mMS were related moderately and significantly to IRT, whereas in moderate to advanced glaucoma, mMS was more strongly correlated with IRT than SNR.

Assessments of tear meniscus height, tear film thickness, and corneal epithelial thickness after deep anterior lamellar keratoplasty

Objective： To assess the lower tear meniscus height（LTMH）, central tear film thickness（CTFT）, and central corneal epithelial thickness（CCET） after deep anterior lamellar keratoplasty（DALK）. Methods： This was a retrospective cross-sectional study of 20 patients who had DALK in one eye over a three-month period. LTMH, CTFT, and CCET of the operated eyes and the unoperated fellow eyes were measured using high-definition optical coherence tomography（HD-OCT）. Correlations between three OCT assessments and age, time following surgery, graft size, bed size, and the number of residual sutures were analyzed. Results： Compared to patients with keratoconus, patients with other corneal conditions had significantly higher CCET in the fellow eye（P=0.024）. For all patients, CCET in the operated eye was significantly negatively correlated with the number of residual sutures（R=-0.579, P=0.008）, and was significantly positively correlated with time following surgery（R=0.636, P=0.003）. In the fellow eye, a significant positive correlation was found between age and CCET（R=0.551, P=0.012）, and a significant negative correlation between age and CTFT（R=-0.491, P=0.028）. LTMH was found to be significantly correlated between operated and fellow eyes（R=0.554, P=0.011）. There was no significant correlation between LTMH and age, bed/graft size, time following surgery, or residual sutures（all possible correlations, P0.05）. Conclusions： Patients with keratoconus tend to have a thinner central corneal epithelium. Corneal epithelium keeps regenerating over time after DALK. DALK did not induce a significant change in tear volume compared with the fellow eye. Postoperative tear function might depend on an individual＇s general condition, rather than on age, gender, bed/graft size, time following surgery, or residual sutures.

Functional tumor imaging based on inorganic nanomaterials

Inorganic nanomaterials have attracted substantial research interest due to their unique intrinsic physicochemical properties. We highlighted recent advances in the applications of inorganic nanoparticles regarding their imaging efficacy, focusing on tumor-imaging nanomaterials such as metal-based and carbon-based nanomaterials and quantum dots. Inorganic nanoparticles gain excellent in vivo tumor-imaging functions based on their specific characteristics of strong near-infrared optical absorption and/or X-ray attenuation capability. The specific response signals from these novel nanornaterials can be captured using a series of imaging techniques, i.e., optical coherence tomography （OCT）, X-ray computed tomography （CT） imaging, two-photon luminescence （TPL）, photoacoustic tomography （PAT）, magnetic resonance imaging （MRI）, surface-enhanced Raman scattering （SERS） and positron emission tomography （PET）. In this review, we summarized the rapid development of inorganic nanomaterial applications using these analysis techniques and discussed the related safety issues of these materials.

Therapeutic effect of osteogenically induced adipose derived stem cells on vascular deprivation-induced osteonecrosis of the femoral head in rabbits

Objective： To explore the therapeutic ef- fect of osteogenically induced adipose-derived stem cells （ADSCs） on vascular deprivation-induced osteonecrosis of the femoral head （ONFH） in rabbit model. Methods： Vascular deprivation-induced ONFH was established by intramuscular injection of methylpre- dnisolone, and vascular occlusion of the capital femoral epiphysis by electrocoagulation in adult New Zealand white rabbits. Eight weeks afLer the establishment of vascular dep- rivation-induced ONFH, animals were randomly divided into three equal groups. In Group A （control）, no therapy was given. In Group B, core decompression was performed by drilling a hole （1.2 mm in diameter） from the outer cortex 2.5 cm distal to the proximal end of the greater trochanter. In Group C, 1 x 107 osteogenically induced ADSCs were resus- pended in 0.5 ml PBS, and then injected directly into the femoral head. Femoral head specimens were obtained at postoperative 8 weeks. The bone formation and three-di- mensional microstructure of the femoral head was evaluated by micro-computed tomography scans （u-CT）. Immunohistochemical analysis was performed to detect the expression ofosteocalcin. Angiogenesis and repair of the femoral head were observed histologically. Results： In trabecular bone at the proximal femur region, the trabecular volume was higher in Group C （130.70 mm3± 4.33 mm3） than that in Groups A （101.07 mm3±7.76 mm3） and B （107.89 mm3±8.6g mm3, P〈0.01）. Bone volume was significantly increased in Group C （40.09 mm3±6.35 mm3） than in Groups A （29.65 mm3±4.61 mm3） and B （31.80 mm3± 4.01 mm3, P〈0.01）. The trabecular number was higher in Groups C （1.58±0.25） than other two groups （1.15±0.18, 1.16± 0.21, P〈0.01）. Bone mineral density showed statistically significant difference between Groups C and A or B （375.38± 23.06） mg HA/ccm, vs （313.73 ± 19.30） mg HA/ccm and （316.09± 16.45） mg HA/ccm, P〈0.01）. Histological examination indicated that there was more new bone formation in Group C than in other groups. Conclusion： Treatment with autologous osteogenically induced ADSCs transplantation results in an enhanced osteogenesis and microstructure of the vascular deprivation-induced osteonecrosis in rabbits.

In-vivo retinal imaging by optical coherence tomography using an RSOD-based phase modulator

Fourier-domain rapid scanning optical delay line (RSOD) was introduced for phase modulation and depth scanning in a time-domain optical coherence tomography (TD-OCT) system. Investigation of parameter optimization of RSOD was conducted. Experiments for RSOD characterization at different parameters of the groove pitch, focal length, galvomirror size, etc. were performed. By implementing the optimized RSOD in our established TD-OCT system with a broadband light source centered at 840 nm with 50 nm bandwidth, in vivo retina imaging of a rabbit was presented, demonstrating the feasibility of high-quality TD-OCT imaging using an RSOD-based phase modulator.

Morphological changes in Schlemm's canal in treated and newly diagnosed untreated glaucomatous eyes

A custom built 1310 nm center wavelength swept source optical coherence tomography instrument was used to measure morphological changes in treated and newly diagnosed untreated glaucomatous human Schlemm’s canal(SC).Thirty-seven primary open-angle glaucoma patients were divided into two groups depending on the patients having been treated or not.The statistical results showed that there were significant differences between the treated and untreated groups’SC areas(treated,7935.6875±680.003μm2;untreated,3890.71875±871.49844μm2;P<0.001),the circumferences(treated,580.37891±44.96529μm;untreated,381.9026±41.22123μm;P<0.001),and the long diameters(treated,272.87806±25.7254μm;untreated,185.24047±19.72786μm;P<0.001).We hypothesize that,after drug treatment,the SC will expand and the morphometric values especially the areas will become larger,thus helping to reduce intraocular pressure.