ObjectivesTo evaluate the reproducibility of Heidelberg retina tomograph (HRT) macular edema module(MEM) measuring the macular retinal thickness.MethodsSixty-two healthy volunteers (9-68 years old) were examined by HRT-II procedure. The retinal signal width (SW) at macula and fovea and macular edema index (E) were recorded for t-test, Pearson linear-correlation analysis. Intra-subject variation repeatedly measured was analyzed with coefficient of variation, 95% tolerance limits of change (TC), and intraclass coefficient of correlation (ICC). ResultsIn healthy individuals, retinal SW was (0.734±0.236) mm at macula，and (0.781±0.243) mm at fovea; macular E was (1.169±0.619). The coefficient of variation repeatedly measured: retinal SW was (8.7±68)%，retinal SW at the fovea was (8.5±6.7)%, and the average was (15.6±13.9)%; 95%TC of intra-subject sequential repeated measurement was 0.131 (8.9%) of retinal SW, 0.137 (10.5%)of fovea SW，and 0.198 (7.4%) of average E. ICC of one individual repeatedly measured by one operator was 0.950 of macular SW, 0.949 of fovea SW, and 0.898 of average edema index.ConclusionsHRT-II MEM is noninvasive, fast and highly reproducible, which provides a new technique to monitor the objective quantification of macular diseases related to retinal thickness. ( Chin J Ocul Fundus Dis, 2005,21:103-105)
Objective To observe the dimensions of the capillary blood vessel arch in central fovea of macula and the foveal avascular area (FAZ), and their relationships with age.Methods Retina in macula of 32 cadavers eyes were isolated . Retinal vessels were immunostained by collagen type IV and examined by confocal laser scanning microscopy. The area and diameter of the FAZ were measured, and the relationship between FAZ and age was analysed. Results The parafoveolar capillary network was observed clearly by confocal laser scanning microscopy. The average area of the FAZ was (0.24±0.13) mm2, and the average diameter was (0.54±0.15) mm. The area and diameter of the FAZ did not show any correlation with age.Conclusions The parafoveolar capillary network could be observed by confocal laser scanning microscopy. The size of the FAZ does not change with age. The dimensions of the parafoveolar capillary network may not be influenced by age. (Chin J Ocul Fundus Dis，2003，19：73-75)
Diabetic retinopathy (DR) is one of the most common causes of visual impairment and blindness in diabetic patients. It is particularly important to set up simpler, safer, non-invasive and highly effective methods for diagnosis as well as monitoring DR. A variety of new fundus imaging techniques show great advantages in early diagnosis, treatment and monitoring of DR in recent years. The main characteristics of wide-field scanning laser imaging system is achieving a large range of retinal image in a single photograph and without mydriasis. It provides several options for color images, FFA and FAF, which satisfy to detect the retina, choroid and vascular structure. Multi spectral fundus imaging system is suitable for DR screening, because it is able to recognize the typical characteristics of DR, such as microaneurysms, hemorrhage and exudation, and is non-invasive and convenient. OCT angiography is a quantitative examination that provides foveal avascular zone area, macular blood flow density, which provides strong evidence for DR diagnosis. The improvement of these new techniques will help us to build up a personalized evaluation system of DR.
Objective To explore the positive rate of scanning laser ophthalmoscope in the retromode (RM-SLO) in different types of diabetic macular edema (DME), and to analyze its correlation with foveal thickness (CMT) and macular volume. MethodsFrom March to May 2021, 40 patients (65 eyes) were diagnosed as DME by fundus examination combined with optical coherence tomography (OCT) in Affiliated Eye Hospital of Wenzhou Medical University at Hangzhou were included in the study. All eyes underwent best corrected visual acuity (BCVA), OCT and RM-SLO fundus imaging examinations, 47 eyes underwent fluorescein fundus angiography (FFA) examination. RM-SLO fundus imaging examinations were performed with Mirante SLO, including retro mode illumination deviated right (RMDR) and retro mode illumination deviated left (RMDL). If one or more of the RMDR and RMDL of the examined patient can identify macular edema, RM-SLO was considered to be able to identify macular edema. The macular volume at CMT and 6 mm from the fovea was measured by OCT software. DME were divided into 3 types based on OCT images: diffuse retinal thinkening (DRT) type; cystoid macular edema(CME) type; serous retinal detachment (SRD) type, focal leakage type, diffuse leakage type and diffuse cystic leakage type. The consistency of RMDR and RMDL in the diagnosis of DME in RM-SLO fundus imaging was evaluated, as well as their positive rate in different classifications of DME. The correlation between the detection of macular edema by RM-SLO and the DME type, CMT and foveal volume, and the correlation between BCVA and edema type, CMT and macular volume were analyzed. ResultsAmong 65 eyes, the positive rates of RMDR and RMDL fundus imaging to detect DME were 46 (70.77%, 46/65) and 48 (73.85%, 48/65), respectively. There was good consistency in identifying DME (Kappa value=0.770; P＜0.001). The positive rates of RMDR and RMDL fundus imaging DRT, CME and SRD type of DME were 42.11% (8/19), 57.89% (11/19), 77.78% (28/36), 77.78% (28/36), 100.00% (10/10), 90.00% (9/10), respectively. In the FFA classification of them, the positive rates of focal leakage, diffuse leakage and diffuse cystic leakage were 68.75% (11/16), 62.50% (10/16), 68.00% (17/25), 76.00% (19/25), 100.00% (6/6), 100.00% (6/6), respectively. The results of Spearman correlation analysis showed that whether RM-SLO could identify DME was associated with CMT and OCT classification (r=0.310, 0.365; P=0.120, 0.003); there was no correlation between FFA classification and macular volume (r=0.113, 0.117; P=0.449, 0.352). BCVA was correlated with CMT and macular volume (r=0.307, 0.269; P=0.013, 0.030), however, there was no significant correlation with OCT type, angiographic type (r=0.051, 0.175; P=0.684, 0.240). ConclusionThe diagnostic agreement of DME are good between RMDR, RMDL of RM-SLO image. DME of DRT type and patients with smaller CMT in OCT are difficult to identified by RM-SLO fundus imaging.
Adaptive optics (AO) is a technique to improve the performance of optical systems by reducing the influence of optical aberrations. Combined with scanning laser ophthalmoscope (AOSLO), the aberration of human refractive system can be corrected. Thus, the resolution and quality of imaging can be greatly improved to the cellular level in vivo retina (such as photoreceptor, nerve fibers, vascular parietal cell), therefore the earlier changes of the diseases can be detected. At the same time, microstructure changes of retinal can also be observed during the follow-up of the disease. Due to inherent technical defects of AOSLO, its wide application in clinical practice is limited. With the continuous progress of AO technology and the further improvement of related software functions, the function of the system will become more stronger and will play a more and more important role in scientific research and clinic.
Objective To observe the corneal nerve fibres damage in different stage of diabetic retinopathy (DR) with type 2 diabetes. Methods A cross-sectional study. One hundred and twenty eyes of 120 patients with type 2 diabetes served as diabetes group. According to International Clinical Diabetic Retinopathy Disease Severity Scales (2002), diabetes patients were classified into 4 subgroups: patients without diabetic retinopathy (NDR), patients with mild or moderate non-proliferative diabetic retinopathy (mNPDR), patients with severe non-proliferative diabetic retinopathy (sNPDR) and patients with proliferative diabetic retinopathy (PDR), each subgroup has 30 eyes of 30 patients. Another 30 eyes of 30 healthy participants served as control group. All eyes were scanned with HRT3 in vivo corneal confocal microscopy. Images of sub-basal nerve plexus were quantified including nerve fiber length (NFL), nerve fiber density (NFD), nerve fiber branch density (NFB), and nerve tortuosity (NT). The correlations of corneal nerve fiber with age, duration of diabetes and glycated hemoglobin (HbA1c) were analyzed using Spearman correlation analysis. Results NFL, NFD and NFB were found to be significantly lower in diabetic patients (F=147.315, 142.586, 65.898;P=0.000, 0.000, 0.000), NT was significantly greater in diabetic patients (F=39.431,P=0.000), when compared to control group. In diabetic patients, NFL, NFD and NFB were gradually reduced with DR severity, NT was gradually increased with DR severity. While the difference of NFL, NFD, NFB, NT was not statistically significant between sNPDR and PDR subgroups (P＞0.05), but was statistically significant between other subgroups (P＜0.05). Spearman correlation analysis results showed that age (r=－0.071, －0.080, 0.001, 0.100;P=0.391, 0.328, 0.991, 0.224) and HbA1c (r=－0.109, －0.115, －0.126, 0.025;P=0.238, 0.211, 0.169, 0.781) had no correlation with NFL, NFD, NFB, NT. Duration of diabetes was negatively correlated with the NFL, NFD (r=－0.212, －0.264;P= 0.020, 0.004), positive correlated with NT (r=0.261,P=0.004), and had no correlation with NFB (r=－0.119,P=0.194). Conclusions Corneal nerve fiber loss and nerve tortuosity increased were found in patients with type 2 diabetes, and even without diabetic retinopathy. The progress of corneal neuropathy was correlated with the severity of DR, but it was not change significantly between sNPDR and PDR.
Objective To verify the applicable significance of confocal scanning laser retinal tomography in agerelated macular degeneration (AMD). Methods Heidelberg confocal scanning laser tomography was used to measure 75 eyes of 59 patients with AMD, including 25 eyes of 20 patients with exudative AMD, 25 eyes of 16 patients with atrophic AMD, and 25 eyes of 23 patients with macular drusen. The differences of the width, volume and maximum height of Z profile signal of macula were analyzed. Results Z profile signal width in macular tomography of exudative AMD was wider than that of macular drusen; maximum height and volume in macular tomography of exudative AMD were larger than that of macular drusen (P＜0.01); Z profile signal width, maximum height，and volume in macular tomography of atrophic AMD were wider and larger than that of macular drusen (P＜0.05). Macular volume of exudative AMD was obviously larger than that of atrophic AMD (P＜0.01). Conclusion Confocal scanning laser tomography may be one of the useful methods for objective evaluation of morphologic change for the development of AMD. (Chin J Ocul Fundus Dis, 2002, 18: 262-265)
Objective To observe the expression of Nogo66 receptor （NgR）in ratsprime; retina during the postnatal development． Methods The expression of NgR in 48 rats were observed by immunofluorescence histochemistry and laserconfocal microscopy 0, 3, 7, 14, 21, 35, 49, 63 days after birth, with 6 rats in each group, respectively． Results The expression of NgR is positive in the retina in the whole duration of growth, and the fluorescence pigmentation was located around the ganglion cell nuclaear. Conclusion The positive expression of NgR suggests that the interaction of NgR and CNS myelin inhibitors not only inhibit neuronal plasticity but also promote it, which could regulate neuronal plasticity.
Confocal scanning laser ophthalmoscope imaging superimpose two or three kinds of lasers to obtain images of different layers of retina, and then synthesize a pseudo-color fundus image by computer. Confocal scanning laser ophthalmoscope is widely used in outpatient fundus pre-examination and epidemiological screening of large samples due to its features of non-mydriatic, fast imaging, simple operation and high degree of patient cooperation. It has good clinical and scientific application value in the diagnosis and treatment of a variety of fundus diseases. Because of there is still a lack of unified standards for laser fundus photos in China, it is necessary to correctly identify the common fundus lesions in confocal scanning laser ophthalmoscope and to summarize and popularize the method of reading the photos in layers. In addition, we should give full play to the its advantage of layering and locating, and reasonably choose the combination of OCT, OCT angiography, FFA, ICGA, ultrasonography, so as to maximize its clinical application value and help clinical diagnosis.
ObjectiveTo analyze the diagnostic value of multicolor scanning laser imaging (confocal scanning laser ophthalmoscopy, cSLO) combined with swept-source optical coherence tomography (SS-OCT) for lacquer cracks (LC) and myopia stretch lines (MSL) of pathological myopia.MethodsA observational study. A total of 83 eyes of 58 patients with pathological myopia were recruited from May 2017 to January 2018 in Department of Ophthalmology of The First People’s Hospital Affiliated to Shanghai Jiao Tong University. Among 58 patients, 20 were males (30 eyes) and 38 were females (53 eyes). The mean age was 50.65±12.02 (range from 24 to 70) years old; the average BCVA was 0.37±0.32; the average diopter was −11.38±4.96 D; and the average axial length was 28.91±2.15 mm. All participants underwent FFA and ICGA examination to obtain FFA, ICGA, infrared light reflection (IR) and autofluorescence (AF) images. SS-OCT was applied for scanning macular and optic disc at 9 mm × 9 mm range. cSLO was performed with macular as the center. All images were inspected carefully by three independent observers and the consistency test was detect. LC were diagnosed as hyperreflective line in FFA and hypofluorescent linear lesions in late ICGA. MSL were defined as both hypofluorescent linear lesions in FFA and late ICGA. The accuracy of each inspection item in the diagnosis of LC was detected. The optimal technique was applied with SS-OCT to further explore the detection rate of LC.ResultsThe intra-observer reproducibility was good to excellent for all measurements (Kappa=0.938, P＜0.01). The positive detection rate of LC and MSL was highest in the standard images of cSLO (77.1%), followed by SS-OCT red free (73.1%), fundus photography (72.3%), IR (72.3%) and AF (49.4%). The cSLO was optimal in the test consistency (Kappa=0.520, P＜0.01) and accuracy (the area under the receiver operating characteristic was 0.750). SS-OCT and cSLO were jointly applied to diagnosis of LC and MSL in high myopia. The positive detection rate of LC, MSL and LC+MSL were 91.7%, 91.2% and 93.3% respectively. The characteristics of LC in SS-OCT were irregularities and discontinuous of the RPE-Bruch membrane line, discontinuous inner ellipsoid zone, thinner choroid, an increased light penetrance into deeper tissues, and RPE fracture in severe cases. MSL was mainly manifested as RPE clumps, visible large choroidal vessels protruding and pushing the overlying RPE toward the vitreous.ConclusionsThe diagnosis rate of LC in pathological myopia by cSLO is 77.1%. The standard images of cSLO combined with SS-OCT can diagnose LC, MSL and LC+MSL at rates of 91.7%, 91.2% and 93.3% respectively.