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Contrast sensitivity deficits in patients with mutation-proven inherited retinal degenerations
摘要： Background: Patients with retinal diseases frequently complain of poor visual function even when visual acuity is relatively unaffected. This clinical finding has been attributed to deficits in contrast sensitivity (CS). The purpose of our study was to evaluate the CS in patients with clinical and genetic diagnosis of inherited retinal degeneration (IRD) and relatively preserved visual acuity. Methods: Seventeen patients (30 eyes) with IRD and visual acuity of 20/40 or better, and 18 controls (18 eyes) without any ocular condition underwent slit lamp examination, visual acuity testing via standard Snellen chart testing, CS testing via the Quick Contrast Sensitivity Function (QCSF), and Spectral Domain Optical Coherence Tomography (SD-OCT). CS were measured at 1.0, 1.5, 3.0, 6.0, 12.0, and 18.0 cycles per degree (cpd). T tests with general estimated equations were used to compare CS between groups. Wald chi square followed by pairwise comparisons was used to compare CS between multiple groups. Results: We included 12 patients with rod-cone dystrophy (RCD), 3 patients with Stargardt disease (STGD) and 2 patients with Best disease. Patients with IRD had significantly worse CS than controls (p < 0.001) in all spatial frequencies. Patients with STGD had more marked deficits in CS than patients with Best disease (p < 0.001) and RCD (p < 0.001) despite having similar visual acuities. Conclusion: Patients with IRD, especially patients with STGD with relatively preserved visual acuity have marked deficits in CS when measured across a range of spatial frequencies. We recommend that clinical trials for STGD incorporate CS measured over a range of spatial frequencies as a secondary clinical endpoint for monitoring visual function. CS may provide an explanation for complaints of visual dysfunction when visual acuity is not significantly altered.
关键词： Best disease,Contrast sensitivity,Retinal dystrophy,Retinitis Pigmentosa,Stargardt disease
更新于2025-09-23 15:23:52
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Structural and Functional Outcomes in Chronic Central Serous Chorioretinopathy Treated with Photodynamic Therapy
摘要： Purpose: To study the retinal pigment epithelium (RPE) and retinal alterations in chronic central serous chorioretinopathy treated with photodynamic therapy, and its correlation with functional parameters such as best-corrected visual acuity (BCVA) and contrast sensitivity (CS). Methods: Retrospective, noncomparative, consecutive evaluation by optical coherence tomography and its correlation with BCVA and CS in 31 eyes of 26 patients. Results: In all affected patients, 88.5% were male with a mean age of 42.9 years. The right eye was involved in 64.5% of cases, bilateral in 19% and 73.9% were hyperopic (spherical refraction between 0 and +5.0 diopters). Of these cases, 51.5% had peri-RPE abnormalities, 17.3% hyperreflective substances at RPE, 19.4% RPE atrophy, 55.3% foveolar atrophy, 3.1% pigment epithelial detachment, 5.2% subretinal fluid persistence, 8.3% fibrin deposits, 68.4% photoreceptor inner and outer segment line interruption and 31.1% external limiting membrane interruption. Conclusions: Time evolution and number of outbreaks were related to the decrease in foveal and chorodial thickness and in those with worse BCVA and CS. RPE abnormalities and atrophy were related to the age of onset of symptoms. Photoreceptor elongation has been correlated with poor BCVA and inner and outer segment line destructuring and interruption with poor CS.
关键词： Photochemotherapy,Contrast sensitivity,Visual acuity,Central serous chorioretinopathy,Optical coherence tomography
更新于2025-09-23 15:22:29
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Terahertz Bragg Resonator based on a Mechanical Assembly of Metal Grating and Metal Waveguide
摘要： The physical contrast sensitivity of microwave imaging systems employing scattering-parameter measurements is defined. Methodologies are proposed for its evaluation through measurements and through simulations. This enables the estimation of the smallest detectable target permittivity contrast or size for the system under evaluation. The outcomes of the proposed simulation-based and measurement-based methods are compared for the case of a realistic tissue-imaging system. The agreement between the simulated and measured sensitivity estimation validates the proposed methods. The intention of the proposed methodology is to provide common means to quantify and compare the sensitivity performance of microwave systems used in tissue imaging as well as the antennas used as sensors. We emphasize that the proposed method targets the performance of the hardware and it is not concerned with the image-reconstruction algorithms.
关键词： microwave imaging,tissue sensing,Antenna measurements,receiver sensitivity,response sensitivity,physical contrast sensitivity (PCS)
更新于2025-09-23 15:21:01
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Advances in automotive interior lighting concerning new LED approach and optical performance
摘要： Automotive interior lighting has to follow general trends in lighting and will therefore evolve toward hundreds and even thousands of RGB LEDs per car. Creating mood at day and night, pixelated sign-like information, and theater-like effects like welcome and goodbye messages are examples for outstanding user experience. Furthermore, safety features such as warnings and driving state are a must for autonomous cars. It requires new concepts for the whole interior lighting system to reach premium quality such as data rate (beyond today's bus standard for lighting), support for safety rules, compensation of temperature effects, daylight performance (including huge dimming range for night drive), uniformity in terms of luminance and color along the light guide, and mixing of red, green, and blue (RGB) with white. We report a new automotive RGB light-emitting diode (LED) system that fulfills the above requirements and saves effort as well as cost by calibration before integration. Extensive studies were performed for daylight threshold evaluation with subjects and methods for judging on uniformity for direct-lit RGB light guides based on the contrast sensitivity function and Gaussian fit of the LED luminance profile.
关键词： light guide,human centric lighting,binning,uniformity,automotive,daylight perception,LED,lighting,contrast sensitivity function
更新于2025-09-23 15:21:01
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Disorganization of Retinal Inner Layers (DRIL) and Neuroretinal Dysfunction in Early Diabetic Retinopathy
摘要： To elucidate the relationship between disorganization of retinal inner layers (DRILs) and retinal function in diabetic patients without diabetic retinopathy (DR) and with nonproliferative DR, but without diabetic macular edema (DME). Fifty-seven participants with diabetes mellitus (DM) and 18 healthy controls underwent comprehensive ophthalmic examination, fundus photography, and spectral-domain optical coherence tomography. Scans of the fovea were evaluated for the presence of DRIL. Retinal function was evaluated using Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, the quick contrast sensitivity function (qCSF) on the AST Sentio Platform, short-wavelength automated perimetry (SWAP), standard automated perimetry (SAP), and frequency doubling perimetry (FDP). ANOVA and Kruskal-Wallis were used to compare retinal function in subjects with and without DRIL. Tukey-Kramer test and Wilcoxon were used for post hoc analysis. DRIL was identi?ed in 9 of 57 diabetic subjects. DRIL subjects had higher body mass index and longer diabetes duration compared to diabetic subjects without DRIL (P ? 0.03 and P ? 0.009, respectively). Subjects with DRIL had reduced ETDRS visual acuity (P ? 0.003), contrast sensitivity function (P ? 0.0003), and SAP performance (PSD, P < 0.0001) compared to controls and diabetic subjects without DRIL. Structural analysis revealed inner retinal thinning, and some outer retinal thinning, associated with DRIL. Diabetic subjects with DRIL have reduced retinal function compared to those without DRIL, and defective retinal lamination may be an early cellular consequence of diabetes responsible for this in some patients. Following further longitudinal studies, DRIL may be a readily available and reliable structural biomarker for reduced retinal function in early diabetic neuroretinal disease.
关键词： perimetry,diabetic retinopathy,contrast sensitivity,DRIL,OCT
更新于2025-09-23 15:21:01
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Measuring the Contrast Sensitivity Function Using the qCSF Method With 10 Digits
摘要： Purpose: The Bayesian adaptive quick contrast sensitivity function (qCSF) method with a 10-letter identification task provides an efficient CSF assessment. However, large populations are unfamiliar with letters and cannot benefit from this test. To overcome the barrier, we conducted this study. Method: A new font for digits (0~9) was created. The digits were then filtered with a raised cosine filter, rescaled to different sizes to cover spatial frequencies from 0.5 to 16 cycles per degree (cpd), and used as stimuli in a 10-alternative forced choice (10AFC) digit identification task. With the 10AFC digit identification task, the CSFs of five young and five old observers were measured using the qCSF and Psi methods. The estimates from the latter served as reference. Results: The new digit font showed significantly improved similarity structure, Levene’s test, F(1, 88) ? 6.36, P ? 0.014. With the 10-digit identification task, the CSFs obtained with the qCSF method matched well with those obtained with the Psi method (root mean square error [RMSE] ? 0.053 log10 units). With approximately 30 trials, the precision of the qCSF method reached 0.1 log10 units. With approximately 75 trials, the precision of the CSFs obtained with the qCSF was comparable to that of the CSFs measured by the Psi method in 150 trials. Conclusions: The qCSF with the 10 digit identification task is validated for both young and old observers. Translational Relevance: The qCSF method with the 10-digit identification task provides an efficient and precise CSF test especially for people who are unfamiliar with letters.
关键词： contrast sensitivity function,precision,Bayesian adaptive procedure,qCSF,Sloan digit
更新于2025-09-19 17:15:36
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Assessment of Vitreous Structure and Visual Function after Neodymium:Yttrium–Aluminum–Garnet Laser Vitreolysis
摘要： Purpose: Neodymium:yttriumealuminumegarnet (Nd:YAG) laser treatment is performed on vitreous ?oaters, but studies of structural and functional effects with objective outcome measures are lacking. This study evaluated Nd:YAG laser effects by comparing participants with vitreous ?oaters who previously underwent laser treatment with untreated control participants and healthy persons without vitreous ?oaters using quantitative ultrasonography to evaluate vitreous structure and by measuring visual acuity and contrast sensitivity function to assess vision. Design: Retrospective, comparative study. Participants: One eye was enrolled for each of 132 participants: 35 control participants without vitreous ?oaters, 59 participants with untreated vitreous ?oaters, and 38 participants with vitreous ?oaters previously Nd:YAG-treated. Of these, 25 were dissatis?ed and sought vitrectomy; 13 were satis?ed with observation. Methods: The 39-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-39) to assess participant visual well-being, quantitative ultrasonography (QUS) to measure vitreous echodensity, and best-corrected visual acuity (BCVA) and contrast sensitivity function (CSF) to evaluate vision. Main Outcome Measures: Results of NEI-VFQ-39, QUS, BCVA, and CSF. Results: Compared with control participants without vitreous ?oaters, participants with untreated vitreous ?oaters showed worse NEI-VFQ-39 results, 57% greater vitreous echodensity, and signi?cant (130%) CSF degradation (P < 0.001 for each). Compared with untreated eyes with vitreous ?oaters, Nd:YAG-treated eyes had 23% less vitreous echodensity (P < 0.001), but no differences in NEI-VFQ-39 (P ? 0.51), BCVA (P ? 0.42), and CSF (P ? 0.17) results. Of 38 participants with vitreous ?oaters who previously were treated with Nd:YAG, 25 were dissatis?ed and seeking vitrectomy, whereas 13 were satis?ed with observation. Participants seeking vitrectomy showed 24% greater vitreous echodensity (P ? 0.018) and 52% worse CSF (P ? 0.006). Multivariate linear regression models con?rmed these ?ndings. Conclusions: As a group, participants previously treated with Nd:YAG laser for bothersome vitreous ?oaters showed less dense vitreous, but similar visual function as untreated control participants with vitreous ?oaters. Because some treated eyes showed less dense vitreous and better visual function than those of untreated control participants, a prospective randomized study of Nd:YAG laser treatment of vitreous is warranted, using uniform laser treatment parameters and objective quantitative outcome measures.
关键词： Neodymium:yttriumealuminumegarnet (Nd:YAG) laser,vitreous ?oaters,best-corrected visual acuity,quantitative ultrasonography,contrast sensitivity function
更新于2025-09-12 10:27:22
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A DOUBLE-MASKED, RANDOMIZED, SHAM-CONTROLLED, SINGLE-CENTER STUDY WITH PHOTOBIOMODULATION FOR THE TREATMENT OF DRY AGE-RELATED MACULAR DEGENERATION
摘要： The LIGHTSITE I study investigated the efficacy and safety of photobiomodulation (PBM) treatment in subjects with dry age-related macular degeneration. Thirty subjects (46 eyes) were treated with the Valeda Light Delivery System, wherein subjects underwent two series of treatments (3· per week for 3–4 weeks) over 1 year. Outcome measures included best-corrected visual acuity, contrast sensitivity, microperimetry, central drusen volume and drusen thickness, and quality of life assessments. Photobiomodulation-treated subjects showed a best-corrected visual acuity mean letter score gain of 4 letters immediately after each treatment series at Month 1 (M1) and Month 7 (M7). Approximately 50% of PBM-treated subjects showed improvement of $5 letters versus 13.6% in sham-treated subjects at M1. High responding subjects ($5-letter improvement) in the PBM-treated group showed a gain of 8 letters after initial treatment (P , 0.01) and exhibited earlier stages of age-related macular degeneration disease. Statistically significant improvements in contrast sensitivity, central drusen volume, central drusen thickness, and quality of life were observed (P , 0.05). No device-related adverse events were reported. Photobiomodulation treatment statistically improved clinical and anatomical outcomes with more robust benefits observed in subjects with earlier stages of dry age-related macular degeneration. Repeated PBM treatments are necessary to maintain benefits. These pilot findings support previous reports and suggest the utility of PBM as a safe and effective therapy in subjects with dry age-related macular degeneration.
关键词： contrast sensitivity,best-corrected visual acuity,light-emitting diode,vision loss,low-level light therapy,mitochondria,photobiomodulation,dry age-related macular degeneration,drusen
更新于2025-09-12 10:27:22
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Long pulse millisecond pumped high-average-power linearly polarized single Nd:YAG rod laser
摘要： Human sensitivity to changes in luminance or chromaticity differ as a function of temporal or spatial frequency. Luminance sensitivity is band-pass in shape, while chromatic sensitivity curves are low-pass, along both L–M cone opponent (red–green) and S-cone opponent (blue–yellow) axes, where L, M, and S refer to the long-wavelength middle-wavelength and short-wavelength sensitive cones. Temporal sensitivity curves are supported by the magnocellular pathway for luminance, the parvocellular pathway for L–M modulation and the koniocellular pathway for S-cone modulation. This division largely holds for spatial contrast sensitivity. But there are discrepancies. For example, parvo and konio cells respond to higher temporal and spatial frequencies than can be perceived. Also, the role of eye movements in spatial contrast sensitivity – and spatial vision as a whole – is now debated; the spatial and temporal properties of eye movements profoundly influence the spatiotemporal signal leaving the retina. Finally, human psychophysical thresholds for color and luminance seem largely independent. Yet recent cortical data show much combination of magno, parvo, and konio signals in the cortex. This oddity remains puzzling but may have to do with the segregation of different types of information into dorsal and ventral cortical streams.
关键词： cortical processing,magnocellular pathway,luminance contrast sensitivity,koniocellular pathway,eye movements,temporal frequency,parvocellular pathway,spatial frequency,chromatic contrast sensitivity
更新于2025-09-11 14:15:04
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Novel Triamcinolone Acetonide-Loaded Liposomal Topical Formulation Improves Contrast Sensitivity Outcome After Femtosecond Laser-Assisted Cataract Surgery
摘要： Purpose: To assess visual results, macular modi?cations, and the incidence of clinically signi?cant macular edema (CSME) in patients using a topical triamcinolone acetonide-loaded liposomal formulation (TA-LF) after femtosecond laser-assisted cataract surgery (FLACS). Methods: Fifty-six eyes after FLACS were selected. Twenty-eight eyes in the combined therapy group (P + N) were treated with prednisolone 1% and nepafenac 0.1% for 21 days postoperatively, whereas 28 eyes in the TA-LF group received a liposomal formulation containing 2 mg/mL of TA (0.2%) for the same period of time. Follow-up visits at 1 day, 6 weeks, and 12 weeks after surgery consisted of visual acuity, contrast sensitivity (CS), central foveal thickness (CFT), total macular volume (TMV) measurements, and the detection of CSME. Results: CS improved in the TA-LF group (basal value: 1.087 – 0.339 vs. 1.276 – 0.147 at week 12, P = 0.0346), whereas in the P + N group, CS was not different from the baseline (basal value: 1.130 – 0.331 vs. 1.274 – 0.133 at week 12, P = 0.1276). There were similar increases in postoperative CFT and TMV in both groups. CFT and TMV signi?cantly correlate with CS only in the TA-LF group. The r2 for CFT and CS was 0.1963 (P = 0.0206), whereas the r2 for TMV and CS was 0.3615 (P = 0.0007) at 12 weeks. No difference was observed in the incidence of CSME between the groups. Conclusion: TA-LF is associated with better CS outcomes compared to combined therapy after FLACS.
关键词： femtosecond laser-assisted cataract surgery,macular edema,liposomes,visual outcomes,contrast sensitivity
更新于2025-09-11 14:15:04