Recent Advances in Imaging Macular Atrophy for Late-Stage Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. In late-stage AMD, geographic atrophy (GA) of dry AMD or choroidal neovascularization (CNV) of neovascular AMD eventually results in macular atrophy (MA), leading to significant visual loss. Despite the development of innovative therapies, there are currently no established effective treatments for MA. As a result, early detection of MA is critical in identifying later central macular involvement throughout time. Accurate and early diagnosis is achieved through a combination of clinical examination and imaging techniques. Our review of the literature depicts advances in retinal imaging to identify biomarkers of progression and risk factors for late AMD. Imaging methods like fundus photography; dye-based angiography; fundus autofluorescence (FAF); near-infrared reflectance (NIR); optical coherence tomography (OCT); and optical coherence tomography angiography (OCTA) can be used to detect and monitor the progression of retinal atrophy. These evolving diverse imaging modalities optimize detection of pathologic anatomy and measurement of visual function; they may also contribute to the understanding of underlying mechanistic pathways, particularly the underlying MA changes in late AMD.

Retromode Imaging Modality of Epiretinal Membranes.

(1) Purpose: To determine the characteristics of macular epiretinal membranes (ERM) using non-invasive retromode imaging (RMI) and to compare retromode images with those acquired via fundus autofluorescence (FAF) and fundus photography. (2) Methods: Prospective observational case-series study including patients with macular ERM with no other ocular disease affecting their morphology and/or imaging quality. We compared RMI, FAF and fundus photography features by cropping and overlapping images to obtain topographic correspondence. (3) Results: In total, 21 eyes (21 patients) affected by ERM were included in this study. The mean area of retinal folds detected by RMI was significantly higher than that detected by FAF (11.85 ± 3.92 mm2 and 5.67 ± 2.15 mm2, respectively, p < 0.05) and similar to that revealed by fundus photography (11.85 ± 3.92 mm2 and 10.58 ± 3.45 mm2, respectively, p = 0.277). (4) Conclusions: RMI appears to be a useful tool in the evaluation of ERMs. It allows for an accurate visualization of the real extension of the retinal folds and provides a precise structural assessment of the macula before surgery. Clinicians should be aware of RMI's advantages and should be able to use them to warrant a wide range of information and, thus, a more personalized therapeutic approach.

GCaMP3 expressing cells in the ganglion cell layer of Thy1-GCaMP3 transgenic mice before and after optic nerve injury.

The genetically encoded green fluorescent protein-based calcium sensor, GCaMP, has been used to detect calcium transients and report neuronal activity. We evaluated the specificity of GCaMP3 expression to retinal ganglion cells (RGCs) of the transgenic Thy1-GCaMP3 mouse line in healthy control animals and in those after optic nerve transection (ONT). Retinas from control mice (n = 4) were isolated and stained for RNA-binding protein with multiple splicing (RBPMS) and choline acetyltransferase (ChAT), specific markers for RGCs and cholinergic amacrine cells, respectively. GCaMP3 expression was enhanced with green fluorescent protein (GFP) immunoreactivity. In one subset of animals, ONT was performed 3, 7, or 14 days before sacrifice (n = 4, 4, 4, respectively). Cells positive for GCaMP3, RBPMS, ChAT, as well as the population of co-labeled cells, were quantified. In another subset of animals (n = 4), in vivo confocal scanning laser ophthalmoscope imaging was performed in the same mice at baseline and at 3, 7 and 14 days after ONT. The mean (SD) densities of GCaMP3, RBPMS, and ChAT expressing cells in control retinas were 2663 (110), 3401 (175), and 1041 (47) cells/mm2, respectively. Of the GCaMP3+ cells, 92 (1)% were co-labeled with RBPMS, while 72 (1)% of RBPMS-labeled cells expressed GCaMP3. ChAT expressing cells were not co-labeled with GCaMP3. The number of GCaMP3+ and RBPMS+ cells decreased dramatically after ONT; 78%, 39%, and 18% of GCaMP3+ and 80%, 40%, and 15% of RBPMS+ cells, relative to control retinas, survived at 3, 7, and 14 days after ONT. However, the number of ChAT+ cells did not change. There was a progressive decrease in GCaMP3 fluorescence after ONT in in vivo images. The majority of RGCs in the ganglion cell layer of Thy1-GCaMP3 mice express GCaMP3. There was an expected progressive and specific loss of GCaMP3 expression after ONT. Thy1-GCaMP3 transgenic mice have potential for longitudinal assessment of RGCs in injury models.

Comparison of Blue and Green Confocal Scanning Laser Ophthalmoscope Imaging to Detect Retinal Nerve Fiber Layer Defects.

PURPOSE: We detected retinal nerve fiber layer (RNFL) defects using a confocal scanning laser ophthalmoscopy (CSLO) with both blue and green laser sources and evaluated image quality based on laser wavelength. METHODS: This was a retrospective observational case study. Blue and green CSLO images of 181 eyes with suspected glaucoma were evaluated and compared. Three independent observers identified the presence of RNFL defects and determined which CSLO imaging source provided superior visibility of the defect. After assessing the defect imaging by laser source, demographics and image quality indices of optical coherence tomography between blue better and green better groups were analyzed. RESULTS: Both blue and green CSLO showed high discriminating ability for RNFL defects. The discriminating ability of blue CSLO was significantly greater than that of green CSLO (p = 0.004). Among eyes with a detectable RNFL defect, 61.8% were better visualized with the blue laser compared to the green laser. Compared with the blue better group, the green better group was significantly older (p = 0.009), had a greater proportion of females (p = 0.005), had poorer best-corrected visual acuity (p = 0.001), more severe cataracts (p = 0.001), lower signal strength (p = 0.003), and poor image quality indices (p = 0.001). CONCLUSIONS: Both blue and green CSLO imaging was useful for detecting RNFL defects, but blue CSLO was superior to green CSLO in quality of RNFL defect imaging in most patients with clear media.

Repurposing blue laser autofluorescence to measure ocular sun exposure.

IMPORTANCE: Excessive ocular sun exposure is linked to various eye pathologies. Conjunctival ultraviolet autofluorescence (CUVAF) is a method of detecting sun-related conjunctival damage; however, the custom-built camera system required is not readily available. BACKGROUND: We investigated whether blue laser autofluorescence (BAF) on a commonly used confocal scanning laser ophthalmoscope (cSLO) can be utilized to measure CUVAF area. DESIGN: Cross-sectional evaluation of a diagnostic technology at a medical research institute. PARTICIPANTS: Sixty-four participants recruited from three on-going observational eye studies in Western Australia. METHODS: All participants had four images, two of each eye, captured using the CUVAF camera and BAF on the same day. Participants with pterygium or poor quality images were excluded from the analysis. Two graders measured CUVAF area in each image twice. CUVAF area measured by BAF was then compared to measurements determined with the conventional camera system. MAIN OUTCOME MEASURES: CUVAF area. RESULTS: After exclusions, 50 participants' images were analysed. Intra- and inter-observer repeatability were similar between the two systems. When comparing CUVAF area measured by BAF to the camera measurement, grader 1 had a mean difference of +1.00 mm2 , with 95% limits of agreement -5.75 to 7.77 mm2 . Grader 2 had a mean difference of +0.21mm2 , with 95% limits of agreement -7.22 to 7.64 mm2 . CONCLUSIONS AND RELEVANCE: BAF on a commercially available cSLO is a valid method for measuring CUVAF area. This finding provides broader opportunity for identifying, monitoring and educating patients with sun-exposure-related ocular conditions and for researching the ocular impacts of sun exposure.

Diagnostic performance of confocal scanning laser ophthalmoscope imaging and compared with color fundus camera in retinal pigment epithelial detachment of polypoidal choroidal vasculopathy / 中华眼底病杂志

Objective To observe confocal scanning laser ophthalmoscope (cSLO) based retinal imaging and color fundus camera in pigment epithelial detachment (PED) of polypoidal choroidal vasculopathy (PCV).Methods PED of 30 patients (32 eyes) were recruited from June 2016 to June 2017 in the Beijing Tongren Hospital who were detected in high-definition OCT (HD-OCT) and diagnosed as PCV by FFA and ICGA.There were 16 males (17 eyes) and 14 females (15 eyes);aged from 50-83 years,with the mean age of 66.59 years.The photographs of ocular fundus including color fundus camera,cSLO imaging,HD-OCT,FFA and ICGA were analyzed.Multimodal imaging results were regarded as gold standard.Sensitivity and specificity were calculated in serous and hemorrhagic PED diagnosis using color fundus camera and cSLO imaging.The positive number of PED was used to compare between two modes fundus imaging by using x2 test.Results Twenty serous PED eyes,3 hemorrhagic PED eyes and 9 serous/hemorrhagic PED eyes were determined using multimodal imaging.The sensitivity and specificity of color fundus camera were 45％ and 100％ in detecting serous PED and 100％ and 91％ in detecting hemorrhagic PED.The sensitivity and specificity of cSLO imaging were 83％ and 100％ in detecting serous PED and 50％ and 86％ in detecting hemorrhagic PED.The positive number of serous PED in cSLO imaging was significantly higher than color fundus camera (x2=7.752,P=0.011).The positive number of hemorrhagic PED in cSLO imaging shows no obvious difference compared with color fundus camera (x2=1.164,P=0.419).Conclusion The sensitivity and positive number of detecting serous PED with PCV in cSLO fundus imaging were higher than the color fundus camera technology.

Comparison of Blue and Green Confocal Scanning Laser Ophthalmoscope Imaging to Detect Retinal Nerve Fiber Layer Defects

PURPOSE: We detected retinal nerve fiber layer (RNFL) defects using a confocal scanning laser ophthalmoscopy (CSLO) with both blue and green laser sources and evaluated image quality based on laser wavelength. METHODS: This was a retrospective observational case study. Blue and green CSLO images of 181 eyes with suspected glaucoma were evaluated and compared. Three independent observers identified the presence of RNFL defects and determined which CSLO imaging source provided superior visibility of the defect. After assessing the defect imaging by laser source, demographics and image quality indices of optical coherence tomography between blue better and green better groups were analyzed. RESULTS: Both blue and green CSLO showed high discriminating ability for RNFL defects. The discriminating ability of blue CSLO was significantly greater than that of green CSLO (p = 0.004). Among eyes with a detectable RNFL defect, 61.8% were better visualized with the blue laser compared to the green laser. Compared with the blue better group, the green better group was significantly older (p = 0.009), had a greater proportion of females (p = 0.005), had poorer best-corrected visual acuity (p = 0.001), more severe cataracts (p = 0.001), lower signal strength (p = 0.003), and poor image quality indices (p = 0.001). CONCLUSIONS: Both blue and green CSLO imaging was useful for detecting RNFL defects, but blue CSLO was superior to green CSLO in quality of RNFL defect imaging in most patients with clear media.

Clinical application of multicolour scanning laser imaging in diabetic retinopathy.

To compare the visualization of the lesions of diabetic retinopathy (DR) using multicolour scanning laser imaging (MSLI) and conventional colour fundus photography (CFP). The paired images of diabetic patients who underwent same-day MSLI and CFP examinations were reviewed. Combined multicolour (MC) images were acquired simultaneously using three laser wavelengths: blue reflectance (BR, λ = 488 nm), green reflectance (GR, λ = 518 nm) and infrared reflectance (IR, λ = 820 nm). The number of positive DR lesions was calculated using fundus fluorescein angiography as the reference standard. The visibility of the microaneurysms (Mas) was graded using a scale, and the number of Mas for each method was counted by two masked readers. Eighty eyes of 42 diabetic patients were included. The average grading score for Mas visualization was significantly higher with MC (1.50 ± 0.71) and GR (1.55 ± 0.69) than with CFP (0.95 ± 0.81). The average number of Mas was also significantly higher with MC (11.41 ± 14.02) and GR (11.93 ± 13.43) than with CFP (6.43 ± 9.39). The number of positive Mas, diabetic macular edema (DME) and epiretinal membranes (ERM) were significantly higher with MC than CFP (P < 0.05), while the numbers of cotton wool spots, haemorrhages, hard exudates, venous beading and abnormal new vessels were not significantly different (P > 0.05). Mas and ERM were most effectively detected on GR images, and an elevated greenish shift was clearly visualized in patients with DME on the MC images. MSLI can effectively visualize Mas and other pathological lesions of DR compared with CFP. MSLI with superior resolution may be a useful complement for DME and ERM detection.

Multimodal Imaging in Diabetic Macular Edema.

Throughout ophthalmic history it has been shown that progress has gone hand in hand with technological breakthroughs. In the past, fluorescein angiography and fundus photographs were the most commonly used imaging modalities in the management of diabetic macular edema (DME). Today, despite the moderate correlation between macular thickness and functional outcomes, spectral domain optical coherence tomography (SD-OCT) has become the DME workhorse in clinical practice. Several SD-OCT biomarkers have been looked at including presence of epiretinal membrane, vitreomacular adhesion, disorganization of the inner retinal layers, central macular thickness, integrity of the ellipsoid layer, and subretinal fluid, among others. Emerging imaging modalities include fundus autofluorescence, macular pigment optical density, fluorescence lifetime imaging ophthalmoscopy, OCT angiography, and adaptive optics. Technological advances in imaging of the posterior segment of the eye have enabled ophthalmologists to develop hypotheses about pathological mechanisms of disease, monitor disease progression, and assess response to treatment. Spectral domain OCT is the most commonly performed imaging modality in the management of DME. However, reliable biomarkers have yet to be identified. Machine learning may provide treatment algorithms based on multimodal imaging.

Detection of drusen in patients with age-related macular degeneration by retro-mode imaging of F-10 confocal scanning laser ophthalmoscopy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To discuss the application value of retro-mode imaging by F-10 confocal scanning laser ophthalmoscope (cSLO) for detecting drusen in patients with age-related macular degeneration (AMD).METHODS:This was a retrospective case study.During the period of October 2015 to December 2016, 67 patients with unilateral AMD (67 affected eyes and 67 fellow eyes) were included in this study.All patients underwent color fundus photography, optical coherence tomography (OCT) and retro-mode imaging by F-10 cSLO.The features of drusen by color fundus photography, OCT and retro-mode imaging were comparatively observed in the affected eyes of patients with unilateral AMD.Positive numbers of drusen in the fellow eyes of patients with unilateral AMD detected by color fundus photography, OCT and retro-mode imaging were calculated and compared.RESULTS:Retro-mode imaging by F-10 cSLO gave easier to identify images of drusen than color fundus photography and OCT in the affected eyes of patients with unilateral AMD.In the fellow eyes of 67 patients with unilateral AMD, retro-mode imaging showed drusen in 56 cases(84%), color funds photography showed drusen in 36 cases(54%), OCT showed drusen in 48 cases(72%), the difference was statistically significant(χ2=14.31, P0.0125).CONCLUSION:Retro-mode imaging by F-10 cSLO provides a non-invasive technique and should be useful for detecting and monitoring drusen in AMD.

Imaging performance and quantitative analysis of confocal scanning laser ophthalmoscope for cystoid macular edema / 中华实验眼科杂志

Background Cystoid macular edema (CME) is caused by many fundus diseases.The noninvasive clinical diagnosis methods for CME are conventional color fundus photography up to now.However,these images can not display the CME range well.Confocal scanning laser ophthalmoscope (cSLO) based retinal imaging can provide clear picture with high contrast.However,whether cSLO imaging is feasible in the quantitative assessment of CME remains unclear.Objective This study was to image the boundary of CME and assess the quantification of CME image from cSLO imaging technology.Methods A series case-observational study was designed.This study protocal was approved by Ethic Committee of Beijing Tongren Hospital.cSLO based retinal imaging technology was carried out on consecutive 24 eyes of 24 patients with clinically diagnosed and OCT confirmed CME in Beijing Tongren Eye Center from August to December 2015 under the informed consent of each individual.The radial scan range was 45°× 45 ° and the line scan level was 49 at macula area.The pseudocolar image,green light reflective image (532 nm) and infrared reflective image (785 nm) were collected.The imaging was analyzed by EasyScan software (version 1.2.2).Fundus color photography and SD-OCT were carried out in each patient.The images were graded by specialists according to the SD-OCT cross sectional results.Results The primary causes of CME included epiretinal membrane (10 eyes),branch retinal vein occlusion (BRVO) (6 eyes),central retinal vein occlusion (CRVO) (4 eyes),diabetic retinopathy (DR) (3 eyes) and CRVO with BRVO (1 eye).A CME image was exhibited on the fundus color photogram with the obscure boundary;while the clear range of CME was displayed by the cSLO imaging.The mean score of CME from pseudocolar image,green light reflective image and infrared reflective image was 3.21±0.78,2.67±0.96 and 2.54±0.83,respectively,which was significantly higher than 1.33±0.82 from the fundus color photography (all at P＜0.01).Conclusions In CME patients,the imaging quality from cSLO-based retinal imaging technology is better than that from traditional fundus color photography.Combined with SD-OCT sectional scan analysis,cSLO-based retinal imaging technology may offer a method to observe and record more fundus details for CME diagnosis.

Confocal scanning laser ophthalmoscopy versus modified conventional fundus camera for fundus autofluorescence.

INTRODUCTION: Fundus autofluorescence (FAF) is a noninvasive imaging method to detect fundus endogenous fluorophores, mainly lipofuscin located in the retinal pigment epithelium (RPE). The FAF provides information about lipofuscin distribution and RPE health, and consequently an increased accumulation of lipofuscin has been correlated with ageing and development of certain retinal conditions. Areas covered: An exhaustive literature search in MEDLINE (via OVID) and PUBMED for articles related to ocular FAF in retinal diseases and different devices used for acquiring FAF imaging was conducted. Expert commentary: This review aims to show an overview about autofluorescence in the RPE and the main devices used for acquiring these FAF images. The knowledge of differences in the optical principles, acquisition images and the image post-processing between confocal scanning laser ophthalmoscopy and modified conventional fundus camera will improve the FAF images interpretation when are used as a complementary diagnosis and monitoring tool of retinal diseases.

Topographical Analysis of Non-Glaucomatous Myopic Optic Discs Using a Confocal Scanning Laser Ophthalmoscope (TopSS).

OBJECTIVES: To show normative data of optic discs and the mechanism of glaucoma in people with myopia. DESIGN: Cross-sectional study. PARTICIPANTS: This study investigated 89 Korean adults with myopia but without glaucoma. METHODS: Patients were divided into three groups according to the refractive error: low, moderate, and high; and axial length: normal or below normal length, moderately long, and extremely long. Optic disc variables were obtained by confocal scanning laser ophthalmoscope and compared among groups. RESULTS: The optic disc parameters have a correlation between the refractive error and the optic disc parameters such as average depth, volume below, and half-depth volume. Those parameters also decreased as the axial length increased. The thickness of the volume above decreased significantly as the axial length increased, but a similar relationship was not evident with the refractive error change. In addition, the optic disc parameters were analyzed with respect to the 12 clockwise directions. CONCLUSIONS: Analyses of optic disc parameters provided by TopSS™ revealed the height of the disc decreased as the myopic refractive error and/or axial length increased. The RNFL bundle became compacted in the thinner disc of the myopic population. This could be an explanation for the fragility of the RNFL in the myopic population. The 12 radial section analyses revealed the shallow cupping at the temporal side in the high-myopic, very-long-axis group. The neuroretinal rim (NRR) height significantly decreased at the superior and inferior sides. These findings suggest that the RNFL bundle should be under high mechanical strain in these sectors.

Evaluation of retinal nerve fiber layer thickness and axonal transport 1 and 2 weeks after 8 hours of acute intraocular pressure elevation in rats.

PURPOSE: To compare in vivo retinal nerve fiber layer thickness (RNFLT) and axonal transport at 1 and 2 weeks after an 8-hour acute IOP elevation in rats. METHODS: Forty-seven adult male Brown Norway rats were used. Procedures were performed under anesthesia. The IOP was manometrically elevated to 50 mm Hg or held at 15 mm Hg (sham) for 8 hours unilaterally. The RNFLT was measured by spectral-domain optical coherence tomography. Anterograde and retrograde axonal transport was assessed from confocal scanning laser ophthalmoscopy imaging 24 hours after bilateral injections of 2 µL 1% cholera toxin B-subunit conjugated to AlexaFluor 488 into the vitreous or superior colliculi, respectively. Retinal ganglion cell (RGC) and microglial densities were determined using antibodies against Brn3a and Iba-1. RESULTS: The RNFLT in experimental eyes increased from baseline by 11% at 1 day (P < 0.001), peaked at 19% at 1 week (P < 0.0001), remained 11% thicker at 2 weeks (P < 0.001), recovered at 3 weeks (P > 0.05), and showed no sign of thinning at 6 weeks (P > 0.05). There was no disruption of anterograde transport at 1 week (superior colliculi fluorescence intensity, 75.3 ± 7.9 arbitrary units [AU] for the experimental eyes and 77.1 ± 6.7 AU for the control eyes) (P = 0.438) or 2 weeks (P = 0.188). There was no obstruction of retrograde transport at 1 week (RCG density, 1651 ± 153 per mm(2) for the experimental eyes and 1615 ± 135 per mm(2) for the control eyes) (P = 0.63) or 2 weeks (P = 0.25). There was no loss of Brn3a-positive RGC density at 6 weeks (P = 0.74) and no increase in microglial density (P = 0.92). CONCLUSIONS: Acute IOP elevation to 50 mm Hg for 8 hours does not cause a persisting axonal transport deficit at 1 or 2 weeks or a detectable RNFLT or RGC loss by 6 weeks but does lead to transient RNFL thickening that resolves by 3 weeks.

Characteristics of fundus autofluorscence in patients with atrophic age-related macular degeneration / 中华实验眼科杂志

Background The early diagnosis and treatment is vital for the age-related macular degeneration (AMD).Previous examining methods were fundus fluorescein angiography(FFA)and optical coherence tomography (OCT).However,a new diagnostic technique,fundus autofluorescence(FAF),is applying in ophthalmology.objective This study was to observe the FAF characteristics of atrophic AMD. Methods Thirty-nine eyes of 28 patients with atrophic AMD were diagnosed and collected in our hospital and classified based on the criteria of Chen Song.FAF was performed by a confocal scanning laser ophthalmoscope(Heidelberg Retina Angiograph 2,HRA2).Characteristics of FAF images were compared with FFA images or color fundus photographs.Written informed consent was obtained from each patient prior to the examination. Results Areas with abnormal increased or decreased FAF signals were consisted or unconsisted with funduscopically visible alterations.Seven manifestations of FAF were found in the eyes with preatrophic stage of atrophic AMD,including slight change,focal increase pattern,patchy pattern,linear pattern,lacelike pattern,reticular pattern,and speckled pattern.In atrophic stage of atrophic AMD,geographic atrophy showed a well-defined hypoautofluorescence area;while non-geographic atrophy showed a ill-defined hypoautofluorescence area.There were three abnormal FAF patterns(focal,band and diffuse)in the junctional zone of geographic atrophy and diffuse pattern in the junctional zone of non-geographic atrophy. Conclusion FAF imaging is helpful for the diagnosis of atrophic AMD as a new non-invasive technique.

Quantitative evaluation of experimental choroidal neovascularization by confocal scanning laser ophthalmoscopy: fluorescein angiogram parallels heparan sulfate proteoglycan expression

The objective of the present study was to develop a quantitative method to evaluate laser-induced choroidal neovascularization (CNV) in a rat model using Heidelberg Retina Angiograph 2 (HRA2) imaging. The expression of two heparan sulfate proteoglycans (HSPG) related to inflammation and angiogenesis was also investigated. CNV lesions were induced with argon laser in 21 heterozygous Zucker rats and after three weeks a fluorescein angiogram and autofluorescence exams were performed using HRA2. The area and greatest linear dimension were measured by two observers not aware of the protocol. Bland-Altman plots showed agreement between the observers, suggesting that the technique was reproducible. After fluorescein angiogram, HSPG (perlecan and syndecan-4) were analyzed by real-time RT-PCR and immunohistochemistry. There was a significant increase in the expression of perlecan and syndecan-4 (P < 0.0001) in retinas bearing CNV lesions compared to control retinas. The expression of these two HSPG increased with increasing CNV area. Immunohistochemistry demonstrated that the rat retina damaged with laser shots presented increased expression of perlecan and syndecan-4. Moreover, we observed that the overexpression occurred in the outer layer of the retina, which is related to choroidal damage. It was possible to develop a standardized quantitative method to evaluate CNV in a rat model using HRA2. In addition, we presented data indicating that the expression of HSPG parallels the area of CNV lesion. The understanding of these events offers opportunities for studies of new therapeutic interventions targeting these HSPG.

Influence of Diabetes Mellitus on the Morphometric Analysis of the Optic Nerve Head

To evaluate the influence of diabetes mellitus (DM)on the optic nerve head topographic parameters, each group of 101 patients with open-angle glaucoma (OAG)and 91 control subjects was divided into two subgroups according to the presence or absence of DM.We compared the optic nerve head topographic parameters among groups using Topographic Scanning System (TopSSTM software version 2.2, LDT, Inc., U.S.A.);53 nonglaucomatous eyes without DM (normal group), 38 nonglaucomatous eyes with DM, 67 OAG eyes without DM, and 34 OAG eyes with DM. In the group with OAG without DM, mean contour depth, cup shape, neuroretinal rim area (NRRA), NRRA/disc area were significantly smaller but, effective area and cup/disc area were signifcantly larger than normal group (p<0.05, Student t-test).In nonglaucomatous group, the presence of diabetes showed statistically significant decrease in mean contour depth, cup shape, NRRA, NRRA/disc area ratio (p<0.05).It also showed increase in effective area and cup/disc ratio (p<0.05).These changes were similar to those reported for glaucomatous optic nerve damage.In the group with OAG, the presence of diabetes did not show statistically significant differences in the optic nerve head topographic parameters. In this study, we tried to measure the diabetic changes of the optic nerve head quantitatively using the confocal scanning laser ophthalmoscope (TopSSTM). These results suggest that the diabetic changes should be considered in the evaluation of the optic nerve head parameters for the screening or early diagnosis of open-angle glaucoma when using TopSSTM.

Criteria to Determine the Relevance of the Changes of Disc Parameter to the Progress of the Disease

The purpose of this study is to establish the criteria to discriminate whether the difference of the optic disc parameters compared actually reflects the progress of the disease or it is merely caused by the intraexaminer or interexaminer error. Using the confocal scanning laser ophthalmoscope (TopSS), one eye of each of 20 healthy adults were exmained by the same examiner and one eye of each of 10 adults were examined by different examiners for two consecutive days. The results out of these repeated examinations were analysed to obtain 95%confidence intervals by analysis of the change of the 12 optic disc parameters, and to determine whether the results have been influenced by the disc size or the disc tilt. The criteria to differentiate actual progression of disease from potential errors of the test were obtained. In addition, it was confirmed that changes in the parameters were not influenced by the disc size or the contour tilt. In conclusion,the outcomes of this study can be utilized as a guiding criteria when judging the relevance of the parameter changes to the progress of the disease.

Diagnostic Criteria, Its Sensitivity, and Specificity with the Confocal Scanning Laser Ophthalmoscope TopSSTM

This study was conducted to establish glaucomatous diagnostic criteria and to investigate its sensitivity and specificity with the confocal scanning laser ophthalmoscope(TopSSTM) on the basis of the normal values of the optic disc parameters in previous study. Abnormal ratio of optic disc parameters were analysed in 80 primary open angle glaucoma eyes - the subjects were divided into three groups according to visual field defects, each group of mild, moderate, and severe. and then glaucomatous diagnostic critera was established. According to this diagnostic criteria, we calculated its sensitivity and specificity. We established the glaucomatous diagnostic criteria with high sensitive five parameters(1/2 depth area, C/D ratio, neuroretinal rim area(NRRA), volume above, and notching), the established criteria are 1) If NRRA is decreased, one of the four parameters is abnormal. 2) If NRRA is normal, notching and one of the other three parameters are abnormal. Notching was defined as decreased neuroretinal area at either 6 o/c or 12 o/c sector. With this criteria, the sensitivity was 89.7% in mild group and 100% in moderate and severe groups and the specificity was 89.1% in normal groups. This criteria showed high sensitivity and specificity in the diagnosis of glaucoma, so as to be useful in the early detection of glaucomatous spticdisc changes.

Relationship between Optic Disc Parameters and Myopic Refractive Errors in Myopia

Myopic discs(range: -0.5D) which were taken a confocal scanning laser ophthalmoscope(HRT, Heidelberg Engineering) were analyzed to determine the relationship between optic disc parameters and myopic refractive errors. Regression analysis and coefficient variation were used for a statistic tool. The disc area was not correlated with the myopic refractive error(p=0.21) and showed 16.0% of coefficient of variation. Cup area, cup disc area ratio, rim area, cup volume, rim volume, mean cup depth, maximum cup depth and cup shape measure showed statistically significant correlation with myopic refractive error, respectively(p<0.05). Among these parameters, rim area varied least(within all myopic eyes) with 16.5% of coefficient of variation. As the rim area is the most stable optic disc parameter interindividually in myopic population, it seem to be valuable for follow-up evaluation when a glaucomatous damage is suspected in myopic eyes by calculating its expected normal value with a regression equation.