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 study on the ultrastructural characteristic of segments of photoreceptors from neonatal retinas for supporting donor retina choice of retinal transplantation． Methods Photoreceptors from neonatal calf and adult calf were analysed by scanning electron microscopy and transmission electron microscopy． Results Segments of photoreceptors from neonatal calf appeared the mushroom pattern, in which, distal end of outer segment which was ball-shaped formed the head with mushrooms appearance, and the inner segments along with some of outer segments formed the body with mushrooms appearance． Within the outer segment, plasma membranes of adjacent evaginations form a disk subsequently． The a rray of most disks were vertical to the entire length of segments, but some were parallel and slope to．Owing to the incomplete formation, some rim of disk near distal end of outer segment revealed step-shaped appearance． The distal end of outer segment displays some processes consisted of membranous discs, much vesicular material and mitochondria, much rough endoplasmic reticulum (RER) and numerous polyso mes．Segments of photoreceptor connected with outer nuclear layer via the external limiting membrane． Conclusion The typical morphol ogical structures of outer segments suggest the immature and b gowth ability of photoreceptors of the retina of neonatal calf, and therefore the competence for donor material of retinal transplantation． (Chin J Ocul Fundus Dis, 2001,227-229)
Purpose To observe the pathologic changes of retinal photic injury in mice. Methods A light damaged trunk was designed by ourselves.The mice were given an intermitent light exposure for 3 days,12 hours light exposure every day and 12 hours dark adaption before every exposure.Experimental animals were sacrificed on the 1st,6th,12th,18th and 30th day after light injury,and the eyes were enucleated for light and electronic microscopy observation. Results The early pathologic changes including disc membrance swelling,disorganization in outer segments,and mitochondrial swelling,spherical change in inner segments．Then the chromatin densification,liquefaction and margination,and the shrinkage of nuclear membrance were found in the nuclear layer.Finally the outer nuclear layer became thin and disappeared.The apical microvill of RPE cell disappeared and basic fold became flat in some samples. Conclusion The photoreceptor degeneration was the pathologic characteristic of retinal photic injury in mice. (Chin J Ocul Fundus Dis,1998,14:215-218)
Purpose To verify the effectiveness of combined B-scan ultrasonoscopy and ultrasound biomicroscopy(UBM)imagings in diagnosis of retinal detachments. Methods To contrast the manifestations in vitrectomy operations with the findings of preoperative combined B-scan ultrasonic and UBM examinations in 25 eyes of 25 cases in which 18 eyes with rhegmatogenous retinal detachment and 7 eyes with traumatic retinal detachment were included. Results B-scan ultrasonic imagings were divided into four types: type C,type V,type upsilon; and type gamma;,which included 6 eyes,2 eyes,4 eyes and 11 eyes respectively,and from type C to type gamma;,the retinal detachments manifested themselves from simple posterior segment proliferative vitreoretinopathy(PVR)to both anterior and posterior PVR.The imagings of UBM were divided into 3 types:shallow retinal detachment,retinal circumferential contraction and retinal anterior displacement,which reflected the degree of anterior PVR from lightness to severeness. Conclusions The technique of combined B-scan ultrasonoscopy and UBM can be used to access the severity of the retinal detachments,hence would be beneficial in diagnosing anterior and posterior PVR,designing the surgical precedures and assessing the prognosis. (Chin J Ocul Fundus Dis,1998,14:16-20)
Objective To observe the distribution of human photoreceptor cells at the posterior pole, detect the change of density of the cells affected by eccentricity, and analyze the relationship between the density distribution and the visual sensitivity. Methods Twenty human eye cups with the cornea removed were fixed in 4% polyformaldehyde for 1-4 weeks, and the retinal mounts were observed by differential interference contrast microscope to reveal the retinal cellular configuration and density. The inner segments of photoreceptor cells were first observed from the center to the temporal peripheral part of the retinal mounts. Results The highest density of visual cone cells was at the central fovea (134 000-267 000/mm2, mean 198 090/mm2; CV value:18.2%). The density and individual variation decreased rapidly in the peripheral area. The high density area of rod cells was at the 4 mm of the eccentricity, with the highest value of 72 610-182 350/mm2 and with the high density between 3 and 5 mm. Conclusions The inner segment of photoreceptor cells was monolayer, which may tell the cellular absolute value. The high density of retinal cone cells at the central fovea provide the basis of sensitive central visual acuity, which relates to the individual variation and development. The rod cells have the peak density at the eccentricity with 4 mm, and this area has the greatest sensitivity of dim vision.
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.
Objective To study the progressive development of the retinas through an observation on the histological changes of the retinas from neonatal mice of different day-ages. Methods The retinas from the mice of 1 to 20 days of age were examined by light microscopy,and from 1 to 3 days,by autoradiography. Results The retinas of the mice below 3 days of age only had the RPE cells layer,the neuroblast layer and the ganglion cell layer.With the increase in dayage,the retinas developed gradually and would be mature in the 20th day. Conclusions The retinas of mice is a kind of immature tissue before the 20th days,so it can be considered as transplantation donors. (Chin J Ocul Fundus Dis, 1999, 15: 174-176)
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)
Multicolor imaging (MCI) based on confocal scanning laser ophthalmoscopy can gather more diagnostic information than traditional fundus photographs through utilizing three wavelengths of laser to scan posterior retina, which gain different layer reflected signal since the depth of penetration into retina is different for each wavelength. Currently, it provides important information and reference value for diagnose of different layer diseases on retina or choroid combining MCI with OCT, FAF, FFA and so on. However, there are still misunderstandings in the diagnosis of retinal diseases with MCI. Careful observation of retinal details in MCI, CFP and other imaging methods is more conducive to the correct diagnosis of fundus ophthalmopathy.
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.