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.
ObjectiveTo compare the imaging characteristics and detection of various types of lesions in diabetic retinopathy (DR) with colorful laser scanning fundus imaging (MSLI) and traditional color fundus photography (CFP).MethodsProspective case series observational study. A total of 38 eyes of 38 patients with DR diagnosed by clinical examination were included in the study. Among them, 21 were male and 17 were female; the mean age was 62.6±11.2 years; the average duration of diabetes was 14.3±7.5 years. All the patients were performed CFP, MSLI, frequency domain optical coherence tomography (SD-OCT), fluorescein angiography (FFA) examination. Using the Helielberg Spectralis HRA+OCT MSLI inspection, one scan simultaneously obtained 488 nm blue reflection (BR), 515 nm green light reflection (GR), 820 nm infrared light reflection (IR), and multicolor image (MC). The detection of traditional CFP and MC on microaneurysm (MA), hard exudation (HEX), cotton plaque (CWS), intraretinal hemorrhage (IRH), intraretinal microvascular abnormality (IRMA), venous bead (VB), venous ring (VL), macular edema (DME), macular anterior membrane (MEM) and laser photocoagulation (LB) were comparatively observed. The results of FFA examination were used as the diagnostic criteria for lesions. SD-OCT was used to determine the location and depth of lesions and the diagnostic reference for DME and MEM.ResultsThe numbers of eyes with MA (χ2=10.460), DME (χ2=4.006), MEM (χ2=4.444) was significantly higher in MC than that of traditional CFP. But the number of eyes with IRH (χ2=0.103), CWS (χ2=1.515), HEX (χ2=0.227), IRMA (χ2=0.051), VB (χ2=0.001), VL (χ2=0.149), VH (χ2=0.693) and LB (χ2=0.720) were not statistically significant between two methods (P>0.05). The imaging quality of MSLI mode is obviously better than that of traditional CFP. Among them, GR imaging shows the best structural changes of superficial retina in MA, CWS, HEX, MEM, etc. IR imaging shows clear depth in deep retina such as LB. DME was green on MC and the weak low-reflection dark area was visible on the IR image, which were consistent with the DME range indicated by the SD-OCT examination.ConclusionsCompared with the traditional CFP, the MSLI can clearly show the DR lesion. The number of checkouts is high on MA, DME and MEM by MC image.
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)
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)
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)
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 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.
Objective To observe the effect of scanning laser ophthalmoscope (SLO) measuring macular light sensibility on evaluating the visual function in idiopathic epiretinal membrane (IERM), and analyze the relationship among the macular light sensibility, central visual acuity, and the thickness of fovea. Methods Procedure of microperimetry of SLO was performed on 44 patients (55 eyes) with IERM diagnosed by indirect and direct ophthalmoscope and optical coherence tomography (OCT). The light sensibility at 10deg;macular central area was measured. The results were compared with 31 healthy control eyes which underwent the same examinations simutaneously. The correlation among the macular light sensibility, the thickness of fovea measured by OCT, and the results of logarithm visual acuity was anaylzed. Results Compared with the control eyes, macular light sensibility decreased in IERM eyes significantly (F=47.265, Plt;0.01), which had the positive correlation with the decrease of visual acuity (r=0.687, P=0.000) and negative correlation with the retinal thickness of macular fovea (r=-0.532,P=0.003). The mean macular light sensitivity in patients with metamorphopsia decreased obviously compared with which in patients without (t=7.039, P=0.000). The mean macular light sensitivity in patients with prolifertive IERM decreased compared with which in patients with dropsical IERM without statistical difference (t=-1.706, P=0.094). Conclusion Microperimetry of SLO may sensitively reflect the macular visual function of eyes with IERM and quantificationally evaluate the changes of macular light sensibility. The changes of macular light sensitivity correlates with the central visual acuity and retinal thickness of macular fovea. (Chin J Ocul Fundus Dis, 2006, 22: 100-102)
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.
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.