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1.
Opt Express ; 32(11): 18700-18716, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859020

RESUMO

A Fe-InP-based planar array antenna-coupled InGaAs/InAlAs multiple quantum well (MQW) optical phase modulator is proposed and demonstrated for radio over fiber (RoF) applications with 60 GHz-band millimeter-wave wireless signals. The modulator comprises five types of five-layer asymmetric coupled quantum wells (FACQWs) and a two-element array antenna. The FACQWs are designed to have a significant electric-field-induced refractive index change with small electric fields induced in the antenna. In the fabricated modulator, a carrier-to-sideband ratio (CSR) of up to 45.9 dB was successfully obtained at a power density of 11 W/m2, corresponding to a phase shift of 10.1 mrad. Furthermore, data transmission of a 2 GHz modulated wave with a 60 GHz wireless carrier wave was demonstrated.

2.
Jpn J Ophthalmol ; 68(3): 183-191, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38598144

RESUMO

PURPOSE: To assess the impact of glaucoma on perceiving three-dimensional (3D) shapes based on monocular depth cues. STUDY DESIGN: Clinical observational study. METHODS: Twenty glaucoma patients, subjected to binocular visual-field sensitivity (binocular-VFS) tests using a Humphrey Visual Field Analyzer, and 20 age-matched healthy volunteers, underwent two tasks: identifying the nearest vertex of a 3D shape using monocular shading (3D-SfS), texture (3D-SfT), or motion (3D-SfM) cues, and distinguishing elementary one-dimensional (1D) features of these cues. The association of the visual-field index (VFI) of binocular-VFS with 3D shape perception in glaucoma patients was also examined. RESULTS: Glaucoma patients demonstrated reduced accuracy in distinguishing 1D luminance brightness and a larger "error-in-depth" between the perceived and actual depths for 3D-SfM and 3D-SfS compared to healthy volunteers. Six glaucoma patients with a 100% VFI for binocular-VFS exhibited a similar error-in-depth to the other fourteen glaucoma patients; they had a larger error-in-depth for 3D-SfM compared to healthy volunteers. No correlation between the error-in-depth values and the VFI values of binocular-VFS was observed. CONCLUSIONS: The 3D shape perception in glaucoma patients varies based on the depth cue's characteristics. Impaired 1D discrimination and larger thresholds for 3D-SfM in glaucoma patients with a 100% VFI for binocular-VFS indicate more pronounced perceptual deficits of lower-level elementary features for 3D-SfS and higher-level visual processing of 3D shapes for 3D-SfM. The effects of the location and degree of binocular visual-field defects on 3D shape perception remain to be elucidated. Our research provides insights into the 3D shape extraction mechanism in glaucoma.


Assuntos
Sinais (Psicologia) , Percepção de Profundidade , Glaucoma , Visão Binocular , Visão Monocular , Campos Visuais , Humanos , Masculino , Feminino , Percepção de Profundidade/fisiologia , Visão Binocular/fisiologia , Campos Visuais/fisiologia , Pessoa de Meia-Idade , Idoso , Glaucoma/fisiopatologia , Glaucoma/diagnóstico , Visão Monocular/fisiologia , Testes de Campo Visual , Pressão Intraocular/fisiologia , Percepção de Forma/fisiologia , Adulto
3.
J Clin Med ; 13(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39124830

RESUMO

Background/Objectives: This study aimed to examine the postoperative changes in the corneal biomechanical properties between solo cataract surgery and solo microhook ab interno trabeculotomy (LOT). Methods: This retrospective case-control study included 37 eyes belonging to 26 patients who underwent solo cataract surgery and 37 eyes belonging to 31 patients who underwent solo µLOT. These two groups were matched according to their preoperative intraocular pressure (IOP), axial length (AL), and age. Corneal Visualization Scheimpflug Technology (Corvis ST) was used to obtain four biomechanical parameters representing the corneal stiffness or corneal deformation at the highest concavity, including stiffness parameter A1 (SP-A1), stress-strain index (SSI), peak distance (PD), and deflection amplitude max (DefAmpMax). These parameters were compared preoperatively and 6 months postoperatively, and between the two surgical groups. Results: Preoperatively, the patients' IOP, age, and AL, as well as their results in four Corvis ST parameters, were similar between the two groups (p > 0.05). No significant difference was observed in SP-A1; however, PD and DefAmpMax were significantly larger, and SSI was significantly smaller postoperatively in the LOT group than in the cataract group. Conclusions: Corneal stiffness was reduced, and the cornea was more deformed with LOT than cataract surgery.

4.
Am J Ophthalmol ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089353

RESUMO

PURPOSE: This study aimed to investigate the usefulness of measuring biomechanical parameters using the Corvis ST to predict the occurrence of hypotony maculopathy and choroidal detachment (CD) following trabeculectomy or bleb needling revision with mitomycin C (MMC). DESING: Clinical cohort study METHODS: This study included 100 eyes of 100 patients who underwent trabeculectomy (88 eyes of 88 patients) or bleb needling (12 eyes of 12 patients) with MMC. A significant predictor of hypotony complications was identified from 1) operation (trabeculectomy or bleb needling), 2) age, 3) sex, 4) disease type (primary open angle glaucoma [POAG], exfoliation glaucoma [EG] or other), 5) lens status (phakia or pseudophakia), 6) preoperative Goldmann applanation tonometry (GAT) intraocular pressure (IOP), 7) preoperative central corneal thickness (CCT), 8) preoperative axial length (AL), 9) preoperative anterior chamber (AC) depth, 10) "Min IOP" (IOP value when hypotony complications occurred, otherwise the minimum IOP during 3 months from trabeculectomy or bleb needling), 11) preoperative corneal curvature, and 12- 24) 12 Corvis ST parameters using multivariate logistic regression. RESULTS: There were 13 and 21 eyes developed hypotony maculopathy and CD, respectively. Male gender, greater preoperative GAT IOP and greater HC deflection Amplitude were significant predictors of the occurrence of hypotony maculopathy (p <0.05). On the other hand, shorter axial length, thinner CCT, greater preoperative GAT IOP and pseudophakia were significant predictors of the occurrence of CD (p <0.05). CONCLUSIONS: A careful attention should be paid to the occurrence of hypotony maculopathy with male gender and greater HC deflection Amplitude despite higher preoperative GAT IOP. Different risk factors were identified; shorter axial length, thinner CCT, greater preoperative GAT IOP and pseudophakia.

5.
Am J Ophthalmol ; 257: 91-102, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37689330

RESUMO

PURPOSE: To investigate factors associated with the severity of prelaminar schisis (PLS) in heathy subjects and glaucoma patients. DESIGN: Prospective cross-sectional study. METHODS: A total of 217 eyes of 217 subjects (110 normal eyes and 107 open angle glaucoma eyes) were studied. Frequency and severity of PLS were compared between normal and glaucomatous eyes. Multivariate logistic models were used to assess factors associated with the severity of PLS. Factors considered were age, axial length, glaucomatous damage indices, Bruch membrane opening (BMO) and anterior scleral canal opening parameters, tractional forces (posterior vitreous staging and presence of Bergmeister papilla), circumpapillary choroidal thickness, lamina cribrosa (LC) parameters, and peripapillary scleral (PPS) angle. RESULTS: The frequency of PLS was 70.9% in normal eyes and 72.0% in glaucomatous eyes. There was no difference in frequency and severity between the groups. The presence of Bergmeister papilla was the strongest predictor of a more severe PLS in both normal and glaucomatous eyes (odds ratio [OR] + 9.78, 12.5; both P < .001). A larger PPS angle in normal eyes (OR = 1.19; P = .003) and a larger BMO area and a deeper LC depth in glaucomatous eyes (OR = 1.08, 1.05; both P = .038) were associated with severity of PLS. CONCLUSIONS: The severity of PLS was strongly associated with the presence of Bergmeister papilla, suggesting a traction-related phenomenon. Correlation of PLS severity with larger BMO area and deeper LC depth, which are optic nerve head structures associated with glaucoma, suggested its possible relationship with glaucomatous damage.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Disco Óptico , Vítreo Primário Hiperplásico Persistente , Humanos , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/diagnóstico , Estudos Transversais , Estudos Prospectivos , Tomografia de Coerência Óptica , Glaucoma/complicações , Glaucoma/diagnóstico , Pressão Intraocular
6.
Am J Ophthalmol ; 263: 99-108, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38403100

RESUMO

PURPOSE: To explore the effects of deep optic nerve head (ONH) structures on Bruch's membrane opening (BMO)-minimum rim width (MRW) and peripapillary retinal nerve fiber layer thickness (pRNFLT) in healthy eyes. DESIGN: Prospective cross-sectional study. METHODS: Two hundred five healthy eyes of 141 subjects (mean ± standard deviation of age and axial length (AXL): 46.9 ± 10.0 years and 24.79 ± 1.15 mm) were enrolled. Best fit multivariable linear mixed models identified factors associated with BMO-MRW and pRNFLT. Explanatory variables included age, gender, AXL, BMO and anterior scleral canal opening (ASCO) area and ovality, magnitude of BMO and ASCO shift, peripapillary choroidal thickness, lamina cribrosa (LC) parameters, prelaminar thickness, and peripapillary scleral (PPS) angle. RESULTS: Thinner BMO-MRW was associated with older age, smaller ASCO/BMO offset magnitude, larger BMO area, thinner prelaminar thickness, deeper LC, and thinner pRNFLT (P = .011, <.001, .004, <.001, <.001, <.001 respectively). Thinner pRNFLT was associated with shorter AXL, smaller ASCO area, a more posteriorly bowed PPS, shallower LC and thinner BMO-MRW. (P = .030, .002, .035, .012, <.001 respectively) CONCLUSIONS: BMO-MRW and pRNFLT were influenced by several deep ONH structures such as BMO and ASCO position shift, BMO or ASCO area, prelaminar thickness, PPS bowing and LC depth in addition to patient characteristics such as age and AXL. The degree and/or direction of associations varied between deep ONH structures and BMO-MRW or pRNFLT. Despite both BMO-MRW and pRNFLT being surrogate parameters for RGC loss, a complex relationship with ONH deep-layer morphology was indicated.


Assuntos
Lâmina Basilar da Corioide , Pressão Intraocular , Fibras Nervosas , Disco Óptico , Células Ganglionares da Retina , Tomografia de Coerência Óptica , Humanos , Lâmina Basilar da Corioide/patologia , Disco Óptico/patologia , Disco Óptico/diagnóstico por imagem , Disco Óptico/anatomia & histologia , Feminino , Masculino , Estudos Transversais , Estudos Prospectivos , Pessoa de Meia-Idade , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Fibras Nervosas/patologia , Adulto , Pressão Intraocular/fisiologia , Idoso , Comprimento Axial do Olho/patologia , Campos Visuais/fisiologia , Voluntários Saudáveis
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