Eighteen structurally diversified sesquiterpenes isolated from Pogostemon cablin and their inhibitory effects on nitric oxide production.

Five new sesquiterpenes, namely, guaianes A-E (1-5), including one novel carbon skeleton guaiane-type sesquiterpene derivatives (1), together with thirteen known compounds (6-18), were isolated from the aerial parts of Pogostemon cablin (Blanco.) Benth. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 1-5 were elucidated on the base of single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations. All compounds were tested for their inhibiting effects on NO production in LPS-stimulated BV2 microglia cells as well as the cell viabilities. The results showed that compounds 2-16 and 18 possessed moderately anti-inflammatory activities at a concentration of 50 µM.

Retinal nerve fibre layer thickness measurements in childhood glaucoma: the role of scanning laser polarimetry and optical coherence tomography.

PURPOSE: A central diagnostic tool in adult glaucoma is the peripapillary retinal nerve fibre layer (pRNFL) thickness. It can be assessed by scanning laser polarimetry (SLP) or optical coherence tomography (OCT). However, studies investigating the relevance of pRNFL measurements in children are rare. This study aims to compare the glaucoma diagnosing ability of SLP and OCT pRNFL thickness measurements in a paediatric population. METHODS: This retrospective study included 105 children (glaucoma: 22 (21.0%); healthy glaucoma suspects: 83 (79.0%)) aged 4-18 years, examined with SLP (GDxPro/ECC, Carl Zeiss Meditec) and spectral-domain OCT (SPECTRALIS®, Heidelberg Engineering). The thickness of pRNFL sectors was compared between diseased and healthy participants. Areas under the receiver-operating characteristic curves (AUC) and logistic regression results were used to compare the glaucoma discriminative capacity between SLP and OCT measurements. RESULTS: Using OCT, pRNFL thickness was decreased in the superior, nasal, and inferior quadrants of glaucoma patients compared to healthy controls (P < 0.001, each). With SLP, such a difference was only observed in the inferior quadrant (P = 0.011). A correlation between glaucoma diagnosis and OCT-measured pRNFL thickness was found in all quadrants (P < 0.001) other than the temporal. With SLP, a correlation was found for the total average thickness (P = 0.037) and inferior quadrant (P = 0.0019). Finally, the AUCs of OCT measurements were markedly higher than those of SLP (e.g., inferior quadrant: OCT 0.83, SLP 0.68). CONCLUSION: pRNFL thickness measurements using both OCT and SLP, correlate notably with the presence of glaucoma. In general, the diagnostic performance of pRNFL thickness measurements seems higher for OCT than for SLP. Thus, pRNFL thickness measurements could provide important information, complementing conventional clinical and functional parameters in the diagnostic process of paediatric glaucoma.

GLAUDIA: A predicative system for glaucoma diagnosis in mass scanning.

Glaucoma is a serious eye disease characterized by dysfunction and loss of retinal ganglion cells (RGCs) which can eventually lead to loss of vision. Robust mass screening may help to extend the symptom-free life for the affected patients. The retinal optic nerve fiber layer can be assessed using optical coherence tomography, scanning laser polarimetry (SLP), and Heidelberg Retina Tomography (HRT) scanning methods which, unfortunately, are expensive methods and hence, a novel automated glaucoma diagnosis system is needed. This paper proposes a new model for mass screening that aims to decrease the false negative rate (FNR). The model is based on applying nine different machine learning techniques in a majority voting model. The top five techniques that provide the highest accuracy will be used to build a consensus ensemble to make the final decision. The results from applying both models on a dataset with 499 records show a decrease in the accuracy rate from 90% to 83% and a decrease in false negative rate (FNR) from 8% to 0% for majority voting and consensus model, respectively. These results indicate that the proposed model can reduce FNR dramatically while maintaining a reasonable overall accuracy which makes it suitable for mass screening.

Microstructural deformation observed by Mueller polarimetry during traction assay on myocardium samples.

Despite recent advances, the myocardial microstructure remains imperfectly understood. In particular, bundles of cardiomyocytes have been observed but their three-dimensional organisation remains debated and the associated mechanical consequences unknown. One of the major challenges remains to perform multiscale observations of the mechanical response of the heart wall. For this purpose, in this study, a full-field Mueller polarimetric imager (MPI) was combined, for the first time, with an in-situ traction device. The full-field MPI enables to obtain a macroscopic image of the explored tissue, while providing detailed information about its structure on a microscopic scale. Specifically it exploits the polarization of the light to determine various biophysical quantities related to the tissue scattering or anisotropy properties. Combined with a mechanical traction device, the full-field MPI allows to measure the evolution of such biophysical quantities during tissue stretch. We observe separation lines on the tissue, which are associated with a fast variation of the fiber orientation, and have the size of cardiomyocyte bundles. Thus, we hypothesize that these lines are the perimysium, the collagen layer surrounding these bundles. During the mechanical traction, we observe two mechanisms simultaneously. On one hand, the azimuth shows an affine behavior, meaning the orientation changes according to the tissue deformation, and showing coherence in the tissue. On the other hand, the separation lines appear to be resistant in shear and compression but weak against traction, with a forming of gaps in the tissue.

Comparing Cone Structure and Function in RHO- and RPGR-Associated Retinitis Pigmentosa.

Purpose: To study cone structure and function in patients with retinitis pigmentosa (RP) owing to mutations in rhodopsin (RHO), expressed in rod outer segments, and mutations in the RP-GTPase regulator (RPGR) gene, expressed in the connecting cilium of rods and cones. Methods: Four eyes of 4 patients with RHO mutations, 5 eyes of 5 patients with RPGR mutations, and 4 eyes of 4 normal subjects were studied. Cone structure was studied with confocal and split-detector adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral-domain optical coherence tomography. Retinal function was measured using a 543-nm AOSLO-mediated adaptive optics microperimetry (AOMP) stimulus. The ratio of sensitivity to cone density was compared between groups using the Wilcoxon rank-sum test. Results: AOMP sensitivity/cone density in patients with RPGR mutations was significantly lower than normal (P < 0.001) and lower than patients with RHO mutations (P < 0.015), whereas patients with RHO mutations were similar to normal (P > 0.9). Conclusions: Retinal sensitivity/cone density was lower in patients with RPGR mutations than normal and lower than patients with RHO mutations, perhaps because cones express RPGR and degenerate primarily, whereas cones in eyes with RHO mutations die secondary to rod degeneration. High-resolution microperimetry can reveal differences in cone degeneration in patients with different forms of RP.

Diagnostic performance of modern imaging instruments in glaucoma screening.

AIM: To evaluate the applicability of imaging devices (spectral-domain optical coherence tomography (Cirrus SD-OCT), scanning laser polarimetry (GDx) and scanning laser ophthalmoscopy (Heidelberg Retinal Tomograph, HRT3)) for glaucoma screening in a middle-aged unselected population. METHODS: Participants of the population-based Northern Finland Birth Cohort Eye Study, aged 45 to 49 years, underwent a comprehensive eye examination including modern imaging with five methods (retinal nerve fibre layer (RNFL) and macular ganglion cell layer +inner plexiform layer (GCIPL) analysis and their combination with SD-OCT, GDx and HRT). The performance of the automated classification of the imaging devices was assessed using a clinical glaucoma diagnosis as reference, that is, the '2 out of 3' rule based on the evaluation of optic nerve head and RNFL photographs and visual fields. RESULTS: We examined 6060 eyes of 3039 subjects; in the clinical evaluation, glaucomatous damage was found in 33 subjects (1.1%) in 43 eyes. The following sensitivities were obtained; RNFL analysis (53%), GCIPL analysis (50%), OCT combination analysis (61%), GDx (56%) and HRT (31%) with corresponding specificities of 95%, 92%, 90%, 88% and 96%. The area under the curve values were 0.76, 0.73, 0.75, 0.75 and 0.73, respectively. Post-test probabilities of glaucoma after positive imaging finding with each of these methods in this unselected population were 11%, 7%, 6%, 5% and 7%, respectively. CONCLUSION: Screening capabilities of the OCT, GDx and HRT were rather similar. The accuracy of all evaluated parameters was only moderate and thus screening with these parameters alone is not reliable.

Intravascular Polarimetry in Patients With Coronary Artery Disease.

OBJECTIVES: The aims of this first-in-human pilot study of intravascular polarimetry were to investigate polarization properties of coronary plaques in patients and to examine the relationship of these features with established structural characteristics available to conventional optical frequency domain imaging (OFDI) and with clinical presentation. BACKGROUND: Polarization-sensitive OFDI measures birefringence and depolarization of tissue together with conventional cross-sectional optical frequency domain images of subsurface microstructure. METHODS: Thirty patients undergoing polarization-sensitive OFDI (acute coronary syndrome, n = 12; stable angina pectoris, n = 18) participated in this study. Three hundred forty-two cross-sectional images evenly distributed along all imaged coronary arteries were classified into 1 of 7 plaque categories according to conventional OFDI. Polarization features averaged over the entire intimal area of each cross section were compared among plaque types and with structural parameters. Furthermore, the polarization properties in cross sections (n = 244) of the fibrous caps of acute coronary syndrome and stable angina pectoris culprit lesions were assessed and compared with structural features using a generalized linear model. RESULTS: The median birefringence and depolarization showed statistically significant differences among plaque types (p < 0.001 for both, one-way analysis of variance). Depolarization differed significantly among individual plaque types (p < 0.05), except between normal arteries and fibrous plaques and between fibrofatty and fibrocalcified plaques. Caps of acute coronary syndrome lesions and ruptured caps exhibited lower birefringence than caps of stable angina pectoris lesions (p < 0.01). In addition to clinical presentation, cap birefringence was also associated with macrophage accumulation as assessed using normalized SD. CONCLUSIONS: Intravascular polarimetry provides quantitative metrics that help characterize coronary arterial tissues and may offer refined insight into coronary arterial atherosclerotic lesions in patients.

Complex vectorial optics through gradient index lens cascades.

Graded index (GRIN) lenses are commonly used for compact imaging systems. It is not widely appreciated that the ion-exchange process that creates the rotationally symmetric GRIN lens index profile also causes a symmetric birefringence variation. This property is usually considered a nuisance, such that manufacturing processes are optimized to keep it to a minimum. Here, rather than avoiding this birefringence, we understand and harness it by using GRIN lenses in cascade with other optical components to enable extra functionality in commonplace GRIN lens systems. We show how birefringence in the GRIN cascades can generate vector vortex beams and foci, and how it can be used advantageously to improve axial resolution. Through using the birefringence for analysis, we show that the GRIN cascades form the basis of a new single-shot Müller matrix polarimeter with potential for endoscopic label-free cancer diagnostics. The versatility of these cascades opens up new technological directions.

The effect of panretinal photocoagulation on confocal laser scanning ophthalmoscopy and stereo photographic parameters of optic disk topography in patients with diabetic retinopathy / Efeito da panfotocoagulação retiniana na oftalmoscopia confocal de varredura a laser e parâmetros da estereofotografia do disco óptico em pacientes com retinopatia diabética

ABSTRACT Purpose: To determine the effect of panretinal photocoagulation on optic disk topographic parameters in non-glaucomatous patients with proliferative diabetic retinopathy. Methods: This was a prospective, single-center, observational study. Thirty-eight eyes of 26 patients with diabetes underwent panretinal photocoagulation for proliferative diabetic retinopathy. Stereoscopic disk photographs and optic nerve head parameters were evaluated using the Zeiss fundus camera and the confocal scanning laser ophthalmoscope (Heidelberg Retinal Tomograph), respectively, at baseline and 12 months after the completion of panretinal photocoagulation. Results: Thirty-eight eyes of 26 patients (15 female) with a mean age of 53.7 (range 26-74) years were recruited. No significant difference was found between the stereo photography determined mean horizontal and vertical cup-to-disk ratio before and after panretinal photocoagulation treatment (p=0.461 and 0.839, respectively). The global values of the optic nerve head parameters analyzed with the HRT3 showed no significant change from baseline to 12 months, including the disk area, cup area, rim area, cup volume, rim volume, cup-to-disk area ratio, linear cup-to-disk ratio, mean cup depth, maximum cup depth, cup shape measure, height variation contour, mean retinal nerve fiber layer thickness, and cross-sectional area. Conclusion: Our results suggest that panretinal photocoagulation does not cause morphological optic disk changes in patients with diabetic proliferative retinopathy after 1 year of follow-up.

RESUMO Objetivo: Determinar o efeito da panfotocoagulação retiniana nos parâmetros topográficos do disco óptico em pacientes não glaucomatosos com retinopatia diabética proliferativa. Métodos: Este é um estudo observacional pros­pectivo e unicêntrico. Trinta e oito olhos de 26 pacientes dia­béticos foram submetidos à panfotocoagulação retiniana para retinopatia diabética proliferativa. As estereofotografias e os parâmetros do disco óptico foram avaliados usando o retinógrafo Visucam da Zeiss e o oftalmoscópio confocal de varredura a laser (Heidelberg Retinal Tomograph), respectivamente, no início e 12 meses após a conclusão da panfotocoagulação. Resultados: Trinta e oito olhos de 26 pacientes (15 mulheres) com média de idade de 53,7 anos (intervalo de 26-74) foram recrutados. Nenhuma diferença significativa foi encontrada entre a média horizontal e vertical para relação escavação/disco óptico determinadas pelas estereo­fotografias antes e após o tratamento com panfotocoagulação retiniana (p=0,461 e 0,839, respectivamente). Os valores globais dos parâmetros do disco óptico analisados com a tomografia de varredura a laser não mostraram nenhuma mudança significativa entre o início até os 12 meses, incluindo disk area, cup area, rim area, cup volume, rim volume, C/D area ratio, linear C/D ratio, mean cup depth, maximum cup depth, cup shape measure, height variation contour, mean retinal nerve fiber layer thickness e cross-sectional area. Conclusão: Nossos resultados sugerem que a panfotocoagulação retiniana não causa alterações morfológicas no disco óptico em pacientes com retinopatia diabética proliferativa após um ano de seguimento.

The effect of panretinal photocoagulation on confocal laser scanning ophthalmoscopy and stereo photographic parameters of optic disk topography in patients with diabetic retinopathy.

PURPOSE: To determine the effect of panretinal photocoagulation on optic disk topographic parameters in non-glaucomatous patients with proliferative diabetic retinopathy. METHODS: This was a prospective, single-center, observational study. Thirty-eight eyes of 26 patients with diabetes underwent panretinal photocoagulation for proliferative diabetic retinopathy. Stereoscopic disk photographs and optic nerve head parameters were evaluated using the Zeiss fundus camera and the confocal scanning laser ophthalmoscope (Heidelberg Retinal Tomograph), respectively, at baseline and 12 months after the completion of panretinal photocoagulation. RESULTS: Thirty-eight eyes of 26 patients (15 female) with a mean age of 53.7 (range 26-74) years were recruited. No significant difference was found between the stereo photography determined mean horizontal and vertical cup-to-disk ratio before and after panretinal photocoagulation treatment (p=0.461 and 0.839, respectively). The global values of the optic nerve head parameters analyzed with the HRT3 showed no significant change from baseline to 12 months, including the disk area, cup area, rim area, cup volume, rim volume, cup-to-disk area ratio, linear cup-to-disk ratio, mean cup depth, maximum cup depth, cup shape measure, height variation contour, mean retinal nerve fiber layer thickness, and cross-sectional area. CONCLUSION: Our results suggest that panretinal photocoagulation does not cause morphological optic disk changes in patients with diabetic proliferative retinopathy after 1 year of follow-up.

Prevalence of glaucoma in the Northern Finland Birth Cohort Eye Study.

PURPOSE: To report the prevalence of glaucoma in the Northern Finland Birth Cohort (NFBC) Eye Study. METHODS: Subjects of the population-based Northern Finland 1966 Birth Cohort (NFBC), aged 45-49 years at the time of the field examination, were randomized to eye screening (50%) and control (50%) groups. The eye examination protocol included best corrected visual acuity (BCVA), measurements of intraocular pressure and central corneal thickness, Humphrey 24-2 perimetry, stereoscopic optic nerve head (ONH) and retinal nerve fibre layer (RNFL) photography and imaging with optical coherence tomography (OCT), scanning laser polarimetry (GDx) and scanning laser ophthalmoscopy (HRT). The diagnosis of glaucoma was made by two independent general ophthalmologists and three independent glaucoma experts based on the evaluation of the ONH and RNFL photographs and the visual fields. RESULTS: Totally, 10 321 subjects of the NFBC main study were alive in Finland in 2011, and they were randomized to the NFBC Eye Study group (n = 5155) and the control group (n = 5166). Of the randomized subjects, 3039 of 5155 (59%) responded and had sufficient data for the study. Glaucoma was suspected in 172 subjects (5.7%) at the first phase of the evaluation protocol. The interobserver agreement between two screening ophthalmologists was moderately good (kappa value 0.54 [95% confidence intervals (CI) 0.46-0.61]). Finally, definite glaucoma was found in 33 subjects (1.1% [95% CI 0.8-1.5]). CONCLUSION: The study provides up-to-date information on the prevalence of glaucoma in a middle-aged Caucasian population in Finland. The baseline data reported here allows the evaluation of the cost-effectiveness of screening later on.

Monocyte infiltration rather than microglia proliferation dominates the early immune response to rapid photoreceptor degeneration.

BACKGROUND: Activation of resident microglia accompanies every known form of neurodegeneration, but the involvement of peripheral monocytes that extravasate and rapidly transform into microglia-like macrophages within the central nervous system during degeneration is far less clear. METHODS: Using a combination of in vivo ocular imaging, flow cytometry, and immunohistochemistry, we investigated the response of infiltrating cells in a light-inducible mouse model of photoreceptor degeneration. RESULTS: Within 24 h, resident microglia became activated and began migrating to the site of degeneration. Retinal expression of CCL2 increased just prior to a transient period of CCR2+ cell extravasation from the retinal vasculature. Proliferation of microglia and monocytes occurred concurrently; however, there was no indication of proliferation in either population until 72-96 h after neurodegeneration began. Eliminating CCL2-CCR2 signaling blocked monocyte recruitment, but did not alter the extent of retinal degeneration. CONCLUSIONS: These results demonstrate that the immune response to photoreceptor degeneration includes both resident microglia and monocytes, even at very early times. Surprisingly, preventing monocyte infiltration did not block neurodegeneration, suggesting that in this model, degeneration is limited by cell clearance from other phagocytes or by the timing of intrinsic cell death programs. These results show monocyte involvement is not limited to disease states that overwhelm or deplete the resident microglial population and that interventions focused on modulating the peripheral immune system are not universally beneficial for staving off degeneration.

A Common Glaucoma-risk Variant of SIX6 Alters Retinal Nerve Fiber Layer and Optic Disc Measures in a European Population: The EPIC-Norfolk Eye Study.

PURPOSE: A common missense variant in the SIX6 gene (rs33912345) is strongly associated with primary open-angle glaucoma (POAG). We aimed to examine the association of rs33912345 with optic disc and retinal nerve fiber layer (RNFL) measures in a European population. METHODS: We examined participants of the population-based EPIC-Norfolk Eye Study. Participants underwent confocal laser scanning tomography (Heidelberg Retina Tomograph II, HRT) to estimate optic disc rim area and vertical cup-disc ratio (VCDR). Scanning laser polarimetry (GDxVCC) was used to estimate average RNFL thickness. The mean of right and left eye values was considered for each participant. Genotyping was performed using the Affymetrix UK Biobank Axiom Array. Multivariable linear regression with the optic nerve head parameter as outcome variable and dosage of rs33912345 genotype as primary explanatory variable was used, adjusted for age, sex, disc area, axial length, and intraocular pressure. We further repeated analyses stratified into age tertiles. RESULTS: In total, 5433 participants with HRT data and 3699 participants with GDxVCC data were included. Each "C" allele of rs33912345 was associated with a smaller rim area (-0.030 mm [95% CI -0.040, -0.020]; P=5.4×10), a larger VCDR (0.025 [95% CI 0.017, 0.033]; P=3.3×10) and a thinner RNFL (-0.39 µm [95% CI -0.62, -0.15]; P=0.001). The RNFL association was strongest in the oldest age tertile, whereas rim area and VCDR associations were strongest in the youngest and oldest age tertiles. CONCLUSIONS: The protein-coding SIX6 variant rs33912345, previously associated with POAG, has a functional effect on glaucoma-associated optic nerve head traits in Europeans.

Laser imaging polarimetry of nacre.

Nacre is a complex biomaterial made of aragonite-tablet bricks and organic mortar that is considerably resilient against breakage. Nacre has been studied with a wide range of laboratory techniques, leading to understanding key fundamentals and informing the creation of bio-inspired materials. In this article, we present an optical polarimetric technique to investigate nacre, taking advantage of the translucence and birefringence of its microcomponents. We focus our study on 3 classes of mollusks that have nacreous shells: bivalve (Pinctada fucata), gastropod (Haliotis asinina and Haliotis rufescens) and cephalopod (Nautilus pompilius). We sent polarized light from a laser through thin samples of nacre and did imaging polarimetry of the transmitted light. We observed clear distinctions between the structures of bivalve and gastropod, due to the spatial variation of their birefringence. The patterns for cephalopod were more similar to bivalve than gastropod. Bleaching of the samples disrupted the transmitted light. Subsequent refilling of the bivalve and gastropod nacre samples with oil produced optical patterns similar to those of unbleached samples. In cephalopod samples, we found that bleaching produced irreversible changes in the optical pattern.

Polarization Variability in Age-related Macular Degeneration.

SIGNIFICANCE: Age-related macular degeneration (AMD) is a leading cause of irreversible vision loss. Complementary imaging techniques can be used to better characterize and quantify pathological changes associated with AMD. By assessing specific light-tissue interactions, polarization-sensitive imaging can be used to detect tissue disruption early in the disease process. PURPOSE: The aim of this study was to compare variability in central macular polarization properties in patients with nonexudative AMD and age-matched control subjects. METHODS: A scanning laser polarimeter (GDx, LDT/CZM) was used to acquire 15 × 15-degree macular images in 10 subjects diagnosed with nonexudative AMD and 10 age-matched control subjects. The coefficient of variation (COV, SD/mean) was used to quantify variability in pixel intensity in the central 3.3° of the macula for custom images emphasizing multiply scattered light (the depolarized light image) and polarization-retaining light (the maximum of the parallel detector image). The intensity COV was compared across subject categories using paired t tests for each image type. RESULTS: The COV in the central macula was significantly higher in the AMD subject group (average, 0.221; 95% confidence interval [CI], 0.157 to 0.265) when compared with matched control subjects (average 0.120; 95% CI, 0.107 to 0.133) in the depolarized light image (P = .01). The COV in the maximum of the parallel detector image was not statistically different between the two subject groups (AMD average, 0.162 [95% CI, 0.138 to 0.185]; control average, 0.137 [95% CI, 0.115 to 0.158]; P = .21). CONCLUSIONS: Variability in multiply scattered light is higher than that of light that is more polarization preserving in patients with nonexudative AMD. Multiple scattering may act as an early indicator representing disruption to the macula in early AMD.

Predictive Factors for Visual Field Conversion: Comparison of Scanning Laser Polarimetry and Optical Coherence Tomography.

PURPOSE: The purpose of this study was to compare the ability of scanning laser polarimetry (SLP) and spectral-domain optical coherence tomography (SD-OCT) to predict future visual field conversion of subjects with ocular hypertension and early glaucoma. METHODS: All patients were recruited from the Erlangen glaucoma registry and examined using standard automated perimetry, 24-hour intraocular pressure profile, and optic disc photography. Peripapillary retinal nerve fiber layer thickness (RNFL) measurements were obtained by SLP (GDx-VCC) and SD-OCT (Spectralis OCT). Positive and negative predictive values (PPV, NPV) were calculated for morphologic parameters of SLP and SD-OCT. Kaplan-Meier survival curves were plotted and log-rank tests were performed to compare the survival distributions. Contingency tables and Venn-diagrams were calculated to compare the predictive ability. RESULTS: The study included 207 patients-75 with ocular hypertension, 85 with early glaucoma, and 47 controls. Median follow-up was 4.5 years. A total of 29 patients (14.0%) developed visual field conversion during follow-up. SLP temporal-inferior RNFL [0.667; 95% confidence interval (CI), 0.281-0.935] and SD-OCT temporal-inferior RNFL (0.571; 95% CI, 0.317-0.802) achieved the highest PPV; nerve fiber indicator (0.923; 95% CI, 0.876-0.957) and SD-OCT mean (0.898; 95% CI, 0.847-0.937) achieved the highest NPV of all investigated parameters. The Kaplan-Meier curves confirmed significantly higher survival for subjects within normal limits of measurements of both devices (P<0.001). Venn diagrams tested with McNemar test statistics showed no significant difference for PPV (P=0.219) or NPV (P=0.678). CONCLUSIONS: Both GDx-VCC and SD-OCT demonstrate comparable results in predicting future visual field conversion if taking typical scans for GDx-VCC. In addition, the likelihood ratios suggest that GDx-VCC's nerve fiber indicator<30 may be the most useful parameter to confirm future nonconversion. (http://www.ClinicalTrials.gov number, NTC00494923; Erlangen Glaucoma Registry).

Retinal degeneration in progressive supranuclear palsy measured by optical coherence tomography and scanning laser polarimetry.

This cross-sectional study compared the retinal morphology between patients with progressive supranuclear palsy (PSP) and healthy controls. (The retinal nerve fiber layer (RNFL) around the optic disc and the retina in the macular area of 22 PSP patients and 151 controls were investigated by spectral domain optical coherence tomography (SD-OCT). Additionally, the RNFL and the nerve fiber index (NFI) were measured by scanning laser polarimetry (SLP). Results of RNFL measurements with SD-OCT and SLP were compared to assess diagnostic discriminatory power. Applying OCT, PSP patients showed a smaller RNFL thickness in the inferior nasal and inferior temporal areas. The macular volume and the thickness of the majority of macular sectors were reduced compared to controls. SLP data showed a thinner RNFL thickness and an increase in the NFI in PSP patients. Sensitivity and specificity to discriminate PSP patients from controls were higher applying SLP than SD-OCT. Retinal changes did not correlate with disease duration or severity in any OCT or SLP measurement. PSP seems to be associated with reduced thickness and volume of the macula and reduction of the RNFL, independent of disease duration or severity. Retinal imaging with SD-OCT and SLP might become an additional tool in PSP diagnosis.

The disc damage likelihood scale: Diagnostic accuracy and correlations with cup-to-disc ratio, structural tests and standard automated perimetry.

Our objective was to compare the diagnostic accuracies of and to determine the correlations between the disc damage likelihood scale (DDLS) and anatomical and functional tests used for glaucoma detection. A total of 54 healthy subjects (54 eyes) and 47 primary open-angle glaucoma patients (47 eyes) were included in this cross-sectional observational study. DDLS scores and cup-to-disc (C/D) ratios were evaluated. Subjects underwent standard automated perimetry (SAP), optic disc and retinal nerve fiber layer (RNFL) imaging with time and spectral-domain optical coherence tomography (TD and SD-OCT), Heidelberg Retina Tomograph (HRT II), and scanning laser polarimetry (GDx-VCC). Areas under the receiver operating characteristic curves (AROCs) for DDLS and diagnostic tests parameters were calculated. DDLS correlations (Spearman's rank) among these parameters were analyzed. Fifty-four eyes were healthy and 47 had glaucoma, including 16 preperimetric glaucoma. DDLS, vertical and horizontal C/D ratios had the largest AROCs (0.92, 0.94 and 0.91, respectively). DDLS diagnostic accuracy was better than the accuracies of HRT II parameters, TD and SD-OCT RNFL thicknesses, and SAP mean deviation (MD) index. There were no significant differences between the accuracies of the DDLS and the C/D ratios, TD-OCT vertical (0.89) and horizontal (0.86) C/D ratios, TD-OCT C/D area ratio (0.89), and GDx-VCC NFI (0.81). DDLS showed significant strong correlations with vertical (r = 0.79) and horizontal (0.74) C/D ratios, and with the parameters vertical C/D ratio and C/D area ratio from HRT II (both 0.77) and TD-OCT (0.75 and 0.72, respectively). DDLS had significant moderate correlations with most of the other structural measurements and SAP MD. The optic disc clinical evaluation with DDLS system and C/D ratio demonstrated excellent accuracy in distinguishing glaucomatous from healthy eyes. DDLS had moderate to strong correlations with most structural and functional parameters. These findings stress the importance of optic disc clinical examination to detect glaucoma in a clinical scenario.

Evaluation of intraretinal migration of retinal pigment epithelial cells in age-related macular degeneration using polarimetric imaging.

The purpose of the present study was to evaluate the intraretinal migration of the retinal pigment epithelium (RPE) cells in age-related macular degeneration (AMD) using polarimetry. We evaluated 155 eyes at various AMD stages. Depolarized light images were computed using a polarization-sensitive scanning laser ophthalmoscope (PS-SLO), and the degree of polarization uniformity was calculated using polarization-sensitive optical coherence tomography (OCT). Each polarimetry image was compared with the corresponding autofluorescence (AF) images at 488 nm (SW-AF) and at 787 nm (NIR-AF). Intraretinal RPE migration was defined by the presence of depolarization at intraretinal hyperreflective foci on PS-SLO and PS-OCT images, and by the presence of hyper-AF on both NIR-AF and SW-AF images. RPE migration was detected in 52 of 155 eyes (33.5%) and was observed in drusenoid pigment epithelial detachment (PED) and serous PED with significantly higher frequencies than in other groups (P = 0.015). The volume of the migrated RPE cluster in serous PED was significantly correlated with the volume of the PED (R2 = 0.26; P = 0.011). Overall, our results showed that intraretinal RPE migrations occurred in various AMD stages, and that they occurred more commonly in eyes with serous and drusenoid PED.

Three-Dimensional Geometry of Collagenous Tissues by Second Harmonic Polarimetry.

Collagen is a biological macromolecule capable of second harmonic generation, allowing label-free detection in tissues; in addition, molecular orientation can be determined from the polarization dependence of the second harmonic signal. Previously we reported that in-plane orientation of collagen fibrils could be determined by modulating the polarization angle of the laser during scanning. We have now extended this method so that out-of-plane orientation angles can be determined at the same time, allowing visualization of the 3-dimensional structure of collagenous tissues. This approach offers advantages compared with other methods for determining out-of-plane orientation. First, the orientation angles are directly calculated from the polarimetry data obtained in a single scan, while other reported methods require data from multiple scans, use of iterative optimization methods, application of fitting algorithms, or extensive post-optical processing. Second, our method does not require highly specialized instrumentation, and thus can be adapted for use in almost any nonlinear optical microscopy setup. It is suitable for both basic and clinical applications. We present three-dimensional images of structurally complex collagenous tissues that illustrate the power of such 3-dimensional analyses to reveal the architecture of biological structures.