Adaptive optics scanning laser ophthalmoscopy may support early diagnosis of glaucoma

Purpose: To compare image characteristics of retinal nerve fiber layer (RNFL) between glaucoma patients and healthy controls using adaptive optics scanning laser ophthalmoscopy (AOSLO). Methods: This was a cross-sectional pilot study with two groups: a glaucoma group with patients with moderate or severe glaucoma as per the Hodapp–Parrish–Anderson classification system and a control group with healthy individuals. The optic nerve damage in moderate glaucoma was predominantly located in only one hemisphere; the other hemisphere was un- or minimally affected on optical coherence tomography and automated perimetry and is referred to as early glaucoma. The structure of RNFL bundles and gain (%) in RNFL images with mean pixel values between 15 and 35 were analyzed. Imaging was performed one degree away from the optic disc margin at two and four cardinal clock positions in the glaucoma and control groups, respectively. The field of view was 1.3° at 2.3 ? resolution. We studied one eye per participant. Results: There were 11 glaucoma patients and 7 healthy controls. Imaging was successful at 88% of the locations in controls and early glaucoma; the reflectivity differed significantly (0.51 and 0.56, respectively, P < 0.001) but not the structure of RNFL bundles (Cohen’s Kappa 0.11) between them. In patients with moderate and severe glaucoma, imaging was successful only at 46% of the locations; RNFL bundles were not discernible, and RNFL reflectivity did not differ from those with early glaucoma (P < 0.11). Conclusion: The recorded gain (%) of RNFL images obtained using AOSLO could be an objective indicator of early glaucoma

Normative data of retinal arteriolar and venular calibre measurements determined using confocal scanning laser ophthalmoscopy system – Importance and implications for study of cardiometabolic disorders

Purpose: To determine and validate retinal vascular caliber measurements by using the confocal scanning laser ophthalmoscopy system. Retinal vasculature changes are often regarded as clinical markers for systemic disease. Methods: It was a prospective observational study conducted on 600 eyes of 300 normal subjects with no systemic or ocular illness from January 1, 2016 to June 30, 2017 in a tertiary referral eye center. Non?mydriatic infrared reflectance, blue reflectance, and blue peak blue autofluorescence fundus imaging were done on the confocal scanning laser ophthalmoscopy system. The dimensions of the retinal vessels were measured using inbuilt calipers at 1800 ?m from the center of the optic disc. Internal and external dimensions were measured. Observer variation and its comparison using Image J software were assessed. Results: The median age was 29 years (18–50 years). Mean internal and external diameters for arterioles were 85.1 ± 12.4 ?m and 105.0 ± 12.0 ?m, and for venules were 133.8 ± 16.6 ?m and 145.4 ± 16.1 ?m, respectively. The mean internal and external wall thicknesses were 19.7 ± 8.0 ?m and 11.0 ± 5.6 ?m, and wall thickness?to?lumen ratios were 0.3 ± 0.1 and 0.1 ± 0.1, respectively. Arteriolar?to?venular ratio for lumen and vessel was 0.66 ± 0.1 and 0.74 ± 0.1, respectively. There was no statistically significant difference between age groups. Both inter? and intra?observer reproducibility was >95%. The Bland–Altman plot showed that the difference between measurements using both confocal scanning laser ophthalmoscopy and Image J software lies within the limits of agreement approximately 95% of the time. Conclusion: This is the first effort to develop a normative database by using a simple non?invasive confocal scanning laser ophthalmoscopy system with high observer reproducibility

Effect of High Myopia on Optic Nerve Head by Confocal Scanning Laser Ophthalmoscopy in Nepalese Eyes

PURPOSE: To compare parameters of confocal scanning laser ophthalmoscopy (Heidelberg Retinal Tomograph [HRT] II) in high myopia with age- and sex-matched emmetropes. METHODS: A hospital-based cross-sectional study was conducted among Nepalese subjects aged 18 to 35 years at BP Koirala Lions Centre for Ophthalmic Studies, Institute of Medicine, Maharajgunj, Kathmandu from November 2015 to October 2016. Fifty consecutive subjects with high myopia (spherical equivalent ranging from −6.00 to −12.00 diopters) and age- and sex-matched emmetropic subjects were enrolled for comparison. Correlations between disc area and other HRT parameters, asymmetry between the right and left eyes, and comparisons between male and female subjects in both high myopic and emmetropic groups were evaluated. RESULTS: Disc area was not significantly (p = 0.11) larger in high myopic eyes than in emmetropic eyes. HRT parameters in highly myopic eyes involved smaller cup parameters and greater rim parameters compared with emmetropic eyes. Disc area was found to be significantly positively correlated with inter disc parameters and significantly negatively correlated with rim to disc area ratio in the high myopia group. Disc area and other intra-disc parameters showed significant correlations between right and left eyes in both high myopia and emmetropia, and no significant differences between males and females from a Nepalese population. CONCLUSIONS: Characteristics of HRT parameters in high myopic eyes involved smaller cup parameters and greater rim parameters compared with emmetropic eyes in a Nepalese population. The effect of disc area on HRT parameters differed significantly only in height variation contour by emmetropic eyes.

Retinal displacement after closure of idiopathic macular hole

Objective:To study the foveal displacement during the closure of idiopathic macular holes (MHs).Methods:Thirty-seven idiopathic MH patients treated by pars plana vitrectomy and internal limiting membrane peeling were studied prospectively. Locations of MH center and foveal pit were measured by optic coherence tomography. Retinal displacement was observed using confocal scanning laser ophthalmoscopy.Results:A total of 40 eyes were included in this study and MHs were closed in 37 eyes (92.5%). The confocal scanning laser ophthalmoscopy showed that all of the retinal capillaries in the superior, inferior, nasal and temporal sides of the MHs moved toward the optic nerve head (ONH). The optic coherence tomography results showed that the mean nasal displacements of foveal pits were (102.9±61.2), (109.6±53.1), and (137.0±52.0) μm at 3, 6 and 12 months, respectively. And the mean vertical displacements were (55.9±49.4), (61.4±57.8) and (67.8±54.3) μm, respectively. Post-operative foveal pits were located in the nasal side of the MH centers. The extension of retina and nasal to the MH were in opposite directions: the nasal hole margin moved toward the MH, but the retina located closer to the ONH moved toward the ONH. The fellow eyes of three patients developed into idiopathic MH during the follow-up period and operations were performed for all of the three patients.Conclusion:Our results showed that center of macula does not move when an idiopathic MH develops, but it moves toward ONH during closure of hole; thus, new fovea is in nasal side of original fovea.

Retinal displacement after closure of idiopathic macular hole

Objective: To study the foveal displacement during the closure of idiopathic macular holes (MHs). Methods: Thirty-seven idiopathic MH patients treated by pars plana vitrectomy and internal limiting membrane peeling were studied prospectively. Locations of MH center and foveal pit were measured by optic coherence tomography. Retinal displacement was observed using confocal scanning laser ophthalmoscopy. Results: A total of 40 eyes were included in this study and MHs were closed in 37 eyes (92.5%). The confocal scanning laser ophthalmoscopy showed that all of the retinal capillaries in the superior, inferior, nasal and temporal sides of the MHs moved toward the optic nerve head (ONH). The optic coherence tomography results showed that the mean nasal displacements of foveal pits were (102.9±61.2), (109.6±53.1), and (137.0±52.0) μm at 3, 6 and 12 months, respectively. And the mean vertical displacements were (55.9±49.4), (61.4±57.8) and (67.8±54.3) μm, respectively. Post-operative foveal pits were located in the nasal side of the MH centers. The extension of retina and nasal to the MH were in opposite directions: the nasal hole margin moved toward the MH, but the retina located closer to the ONH moved toward the ONH. The fellow eyes of three patients developed into idiopathic MH during the follow-up period and operations were performed for all of the three patients. Conclusion: Our results showed that center of macula does not move when an idiopathic MH develops, but it moves toward ONH during closure of hole; thus, new fovea is in nasal side of original fovea.

Uso clínico del tomógrafo de coherencia óptica Spectralis en la evaluación del glaucoma / Use of the Spectralis optical coherence tomography scanner to evaluate glaucoma

La evolución reciente de las herramientas de imagen ha mejorado notablemente la determinación objetiva y cuantitativa de los cambios estructurales en el glaucoma. El tomógrafo de coherencia óptica de dominio espectral, disponible comercialmente, y su módulo Glaucoma Premium Edition recientemente incorporado, ofrece beneficios en la evaluación del glaucoma, por presentar una mayor resolución axial, velocidades de exploración más rápidas, reproducibilidad mejorada, compensación de movimientos oculares, supresión de interferencia y algoritmos avanzados de segmentación. La presente revisión describe las características técnicas, los parámetros de fiabilidad, los protocolos de estudio, la interpretación de los resultados y los principales artefactos que afectan sus medidas. Esta información permite a la comunidad médica realizar un uso y una evaluación adecuada de esta tecnología, y en consecuencia ajustar la gestión clínica según sea necesario(AU)

The recent evolution of imaging tools has notably improved the objective, quantitative determination of structural changes in the glaucoma. The spectral domain optical coherence tomography scanner, commercially available, and its recently incorporated Glaucoma Module Premium Edition, facilitate evaluation of the glaucoma, due to their greater axial resolution, faster exploration speeds, improved reproducibility, eye movement compensation, interference suppression, and advanced segmentation algorithms. The present review describes the technical features, reliability parameters, study protocols, interpretation of results and main artifacts affecting its measurements. Such information will make it possible for the medical community to adequately use and evaluate this technology, adjusting clinical management as required(AU)

Retinal Damage in Chloroquine Maculopathy, Revealed by High Resolution Imaging: A Case Report Utilizing Adaptive Optics Scanning Laser Ophthalmoscopy

A 53-year-old Asian woman was treated with hydroxychloroquine and chloroquine for lupus erythematosus. Within a few years, she noticed circle-shaped shadows in her central vision. Upon examination, the patient's visual acuity was 20 / 25 in both eyes. Humphrey visual field (HVF) testing revealed a central visual defect, and fundoscopy showed a ring-shaped area of parafoveal retinal pigment epithelium depigmentation. Fundus autofluorescence imaging showed a hypofluorescent lesion consistent with bull's eye retinopathy. Adaptive optics scanning laser ophthalmoscope (AO-SLO) revealed patch cone mosaic lesions, in which cones were missing or lost. In addition, the remaining cones consisted of asymmetrical shapes and sizes that varied in brightness. Unlike previous studies employing deformable mirrors for wavefront aberration correction, our AO-SLO approach utilized dual liquid crystal on silicon spatial light modulators. Thus, by using AO-SLO, we were able to create a photographic montage consisting of high quality images. Disrupted cone AO-SLO images were matched with visual field test results and functional deficits were associated with a precise location on the montage, which allowed correlation of histological findings with functional changes determined by HVF. We also investigated whether adaptive optics imaging was more sensitive to anatomical changes compared with spectral-domain optical coherence tomography.

Retinal Damage in Chloroquine Maculopathy, Revealed by High Resolution Imaging: A Case Report Utilizing Adaptive Optics Scanning Laser Ophthalmoscopy

A 53-year-old Asian woman was treated with hydroxychloroquine and chloroquine for lupus erythematosus. Within a few years, she noticed circle-shaped shadows in her central vision. Upon examination, the patient's visual acuity was 20 / 25 in both eyes. Humphrey visual field (HVF) testing revealed a central visual defect, and fundoscopy showed a ring-shaped area of parafoveal retinal pigment epithelium depigmentation. Fundus autofluorescence imaging showed a hypofluorescent lesion consistent with bull's eye retinopathy. Adaptive optics scanning laser ophthalmoscope (AO-SLO) revealed patch cone mosaic lesions, in which cones were missing or lost. In addition, the remaining cones consisted of asymmetrical shapes and sizes that varied in brightness. Unlike previous studies employing deformable mirrors for wavefront aberration correction, our AO-SLO approach utilized dual liquid crystal on silicon spatial light modulators. Thus, by using AO-SLO, we were able to create a photographic montage consisting of high quality images. Disrupted cone AO-SLO images were matched with visual field test results and functional deficits were associated with a precise location on the montage, which allowed correlation of histological findings with functional changes determined by HVF. We also investigated whether adaptive optics imaging was more sensitive to anatomical changes compared with spectral-domain optical coherence tomography.

Role of imaging in glaucoma diagnosis and follow-up.

The purpose of the review is to provide an update on the role of imaging devices in the diagnosis and follow-up of glaucoma with an emphasis on techniques for detecting glaucomatous progression and the newer spectral domain optical coherence tomography instruments. Imaging instruments provide objective quantitative measures of the optic disc and the retinal nerve fiber layer and are increasingly utilized in clinical practice. This review will summarize the recent enhancements in confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography with an emphasis on how to utilize these techniques to manage glaucoma patients and highlight the strengths and limitations of each technology. In addition, this review will briefly describe the sophisticated data analysis strategies that are now available to detect glaucomatous change overtime.

Clinical application of Optovue RTVue OCI' and Heidelberg Retina Tomograph Ⅲ in early diagnosis of glaucoma / 中华实验眼科杂志

Background Many studies showed that attenuation of retinal nerve fiber layer(RNFL)in early glaucoma is one of the important signs.How to accurately and quantitatively measure RNFL thickness is very important for the early diagnosis and monitoring of glaucoma.0bjective This study was to evaluate the clinical value of Optovue RTVue OCT and Heidelberg Retina Tomograph Ⅲ(HRT-Ⅲ)confocal scanning laser ophthalmoscopy in glaucomatous eyes. Methods This cross-sectional study included 40 eyes of 26 patients with suspected open-angle glaucoma(SOAG),48 eyes of 29 patients with open-angle glaucoma and 48 eyes of 27 healthy subjects.Optical nerve head(ONH) parameters and peripapillary RNFL thickness were measured in all the subjects with Optovue RTVue OCT and HRT-Ⅲ,meanwhile all the eyes received perimetry with Humphrey 750-I.Glaucoma variables obtained from Optovue RTVue OCT and HRT-Ⅲ were analyzed among the groups.Topographic Optovue RTVue OCT and HRT-Ⅲ parameters,including disc area(DA),cup area(CA),rim area(RA),rim volume(RV),cup volume(CV),cup/disc area ratio(C/DAR)as well as superior,temporal,inferior and nasal average RNFL thickness,were analyzed.The relationship of ONH parameters and RNFL thickness was analyzed using a linear correlation.The correlation between the mean defect(MD)of the visual field and the tomography parameters in glaucomatous eyes was described by bivariate Pearson correlation coefficients.Resuits The ONH parameters and RNFL thickness obtained by HRT-Ⅲ and OCT showed significant difference(P<0.05).ONH parameters such as RA,C/DAR,CA and RV were statistically changed in SOAG and the POAG patients compared with the normal subjects(q=6.47,q=7.67,P<0.05).The superior and inferior RNFL thickness parameters in three groups were positively correlated between HRT-Ⅲand OCT(r=0.362,r=0.441,r=0.395,P<0.05),Topographic Optovue RTVue OCT and HRT-Ⅲ parameters including CV,CA,RA and C/DAR fitted Pearson analysis(all P<0.05).In POAG group。The RA,RV,CV,C/DAR from Optovue RTVue OCT were correlated with MD with the significant coefficient 0.284,0.286,0.340,0.371 respectively(P<0.05),and evidently correlations also were found between RA,RV,C/DAR with MD respectively with the coefficient 0.339,0.859,0.422(P<0.05)by HRT-Ⅲ. Conclusion Both Optovue RTVue OCT and HRT-Ⅲ can difierentiate ONH analysis with a similar outcome in glaucomatous eye.The C/D value.RA,superior and inferior RNFL thickness based on Optovue RTVue OCT and HRT-Ⅲare distinguishing indexes in the diagnosis of early glaucomatous damage.

Comparison of the diagnostic ability of Moorfield’s regression analysis and glaucoma probability score using Heidelberg retinal tomograph III in eyes with primary open angle glaucoma.

Purpose: To compare the diagnostic performance of the Heidelberg retinal tomograph (HRT) glaucoma probability score (GPS) with that of Moorfield’s regression analysis (MRA). Materials and Methods: The study included 50 eyes of normal subjects and 50 eyes of subjects with early-to-moderate primary open angle glaucoma. Images were obtained by using HRT version 3.0. Results: The agreement coefficient (weighted k) for the overall MRA and GPS classification was 0.216 (95% CI: 0.119 – 0.315). The sensitivity and specificity were evaluated using the most specific (borderline results included as test negatives) and least specific criteria (borderline results included as test positives). The MRA sensitivity and specificity were 30.61 and 98% (most specific) and 57.14 and 98% (least specific). The GPS sensitivity and specificity were 81.63 and 73.47% (most specific) and 95.92 and 34.69% (least specific). The MRA gave a higher positive likelihood ratio (28.57 vs. 3.08) and the GPS gave a higher negative likelihood ratio (0.25 vs. 0.44).The sensitivity increased with increasing disc size for both MRA and GPS. Conclusions: There was a poor agreement between the overall MRA and GPS classifications. GPS tended to have higher sensitivities, lower specificities, and lower likelihood ratios than the MRA. The disc size should be taken into consideration when interpreting the results of HRT, as both the GPS and MRA showed decreased sensitivity for smaller discs and the GPS showed decreased specificity for larger discs.

The Optical Coherence Tomography Analysis of Hyperfluorescence by Scanning Laser Ophthalmoscope in Central Serous Chorioretinopathy

PURPOSE: To analyze the optical coherence tomography (OCT) result at the area of hyperfluorescence by scanning laser ophthalmoscopy (SLO) in central serous chorioretinopathy. METHODS: We investigated sensory detachment, pigment epithelial detachment (PED), choroidal neovascularization (CNV), and retinal pigment epithelial atrophy using OCT in the area of hyperfluorescein by scanning laser ophthalmoscopy (SLO) in 29 eyes of 29 patients with CSC. RESULTS: Of 29 eyes, no specific finding was noted in 19 eyes. Small PED corresponding to the leaking point was noted in 3 eyes, large serous PED with leaking point in 2 eyes, hemorrhagic PED in 1 eye, subretinal precipitate and PED in 1 eye, and retinal pigment epithelial atrophy in 2 eyes. CONCLUSIONS: OCT provided intuitive and objective information on the pathophysiologic state of the retinal pigment epithelial layer at the area of hyperfluorescence by SLO in CSC.

Clinical Usefulness of Infrared image for Subretinal Structure in Chorioretinal Disease

PURPOSE: Scanning laser ophthalmoscope (SLO) has improved Infrared (IR) imaging. Since greater penetration of IR light permitted better visualization of subretinal structures, we evaluated chorioretinal layer in various chorioretinal dieases with SLO. METHODS: Cases of central serous chorioretinopathy (CSC), drusen, age-related macular degeneration (AMD), Vogt-Koyanagi-Harada disease, MEWDS (multiple evanesant white dot syndrome) and inflammatory choroiditis, toxoplasmosis, Stargardt's disease, proliferative diabetic retinopathy (PDR) and submacular hemorrhage were included. We used SLO (101, Rodenstock, Germany) for IR image and compared argon laser image with monochromatic IR image (780 nm wave length). RESULTS: The demarcation and extent of serous retinal detachment and macular star were more distinct in IR image. Small drusen, subretinal deposit and RPE atropy which could not be seen in argon green laser image were visible and appeared brightly with high reflectance in IR image. The CNV membrane which was not seen in full extent in argon laser image were observed completely in IR image. In case of inflammatory choroiditis, patch-like hot spot with surrounding high reflectance was observed in IR image. The subretinal structures and new vessels were clearly visible in IR image despite overlying thick preretinal fibrous prolifertive membrane and vitreous hemorrhage. CONCLUSIONS: The IR image using SLO is a fast and non-invasive diagnostic tool. Compared to fluorescein angiography, IR image gave a improved image for subretinal structure and additional information. Therefore IR imaging is recommended along with clinical symptom, FAG, ICGA for the diagnosis and treatment.