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1.
Proc Biol Sci ; 289(1979): 20220758, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35892218

RESUMO

Animals vary widely in body size within and across species. This has consequences for the function of organs and body parts in both large and small individuals. How these scale, in relation to body size, reveals evolutionary investment strategies, often resulting in trade-offs between functions. Eyes exemplify these trade-offs, as they are limited by their absolute size in two key performance features: sensitivity and spatial acuity. Due to their size polymorphism, insect compound eyes are ideal models for studying the allometric scaling of eye performance. Previous work on apposition compound eyes revealed that allometric scaling led to poorer spatial resolution and visual sensitivity in small individuals, across a range of insect species. Here, we used X-ray microtomography to investigate allometric scaling in superposition compound eyes-the second most common eye type in insects-for the first time. Our results reveal a novel strategy to cope with the trade-off between sensitivity and spatial acuity, as we show that the eyes of the hummingbird hawkmoth retain an optimal balance between these performance measures across all body sizes.


Assuntos
Olho , Mariposas , Animais , Tamanho Corporal , Olho/anatomia & histologia , Insetos
2.
J Morphol ; 283(9): 1182-1199, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35833614

RESUMO

The sizes of the eye structures, such as the lens diameter and the axial length, are important factors for the visual performance and are considered to be related to the mode of life. Although the size of these soft structures cannot be directly observed in fossil taxa, such information may be obtained from measuring size and morphology of the bony scleral ossicle ring, which is present in the eyes of extant saurospids, excluding crocodiles and snakes, and is variously preserved in fossil taxa. However, there have been only a few studies investigating the relationships between the size, the scleral ossicle ring, and soft structures of the eye. We investigated such relationships among the eye structures in extant Squamata, to establish the basis for inferring the size of the soft structures in the eye in fossil squamates. Three-dimensional morphological data on the eye and head region of 59 lizard species covering most major clades were collected using micro-computed tomography scanners. Strong correlations were found between the internal and external diameters of the scleral ossicle ring and soft structures. The tight correlations found here will allow reliable estimations of the sizes of soft structures and inferences on the visual performance and mode of life in fossil squamates, based on the diameters of their preserved scleral ossicle rings. Furthermore, the comparison of the allometric relationships between structures in squamates eyes with those in avian eyes suggest the possibility that the similarities of these structures closely reflect the mechanism of accommodation.


Assuntos
Lagartos , Animais , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Fósseis , Lagartos/anatomia & histologia , Filogenia , Serpentes/anatomia & histologia , Microtomografia por Raio-X
4.
Zhonghua Yan Ke Za Zhi ; 58(2): 96-102, 2022 Feb 11.
Artigo em Chinês | MEDLINE | ID: mdl-35144349

RESUMO

Myopia is a focal issue affecting the eye health of children and adolescents in China. Hyperopia reserve is the refractive state before the occurrence of myopia. As the result of dynamic matching between the axial length, cornea and lens, it is of great significance to the prevention and control of myopia. There has been a lack of the reference basis for children's eyeball development parameters and the influence of genetic factors, especially the changing law of the above-mentioned parameters in the process of children's "emmetropization". To promote the prevention and control of myopia in children and adolescents and to standardize population screening and clinical treatment, based on the survey data of refractive errors in children and adolescents from different regions, a consensus has been reached on the reference interval of hyperopia reserve, axial length and corneal curvature and related genetic factors of emmetropia at different ages among school-age children by the Public Health Ophthalmology Branch of the Chinese Preventive Medicine Association.


Assuntos
Hiperopia , Miopia , Adolescente , Comprimento Axial do Olho , Criança , China/epidemiologia , Consenso , Córnea , Olho/anatomia & histologia , Humanos , Hiperopia/genética , Miopia/genética , Refração Ocular
5.
Chem Biol Interact ; 355: 109804, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35123994

RESUMO

Recent reports have challenged the notion that the lens is immune-privileged. However, these studies have not fully identified the molecular mechanism(s) that promote immune surveillance of the lens. Using a mouse model of targeted glutathione (GSH) deficiency in ocular surface tissues, we have investigated the role of oxidative stress in upregulating cytokine expression and promoting immune surveillance of the eye. RNA-sequencing of lenses from postnatal day (P) 1-aged Gclcf/f;Le-CreTg/- (KO) and Gclcf/f;Le-Cre-/- control (CON) mice revealed upregulation of many cytokines (e.g., CCL4, GDF15, CSF1) and immune response genes in the lenses of KO mice. The eyes of KO mice had a greater number of cells in the aqueous and vitreous humors at P1, P20 and P50 than age-matched CON and Gclcw/w;Le-CreTg/- (CRE) mice. Histological analyses revealed the presence of innate immune cells (i.e., macrophages, leukocytes) in ocular structures of the KO mice. At P20, the expression of cytokines and ROS content was higher in the lenses of KO mice than in those from age-matched CRE and CON mice, suggesting that oxidative stress may induce cytokine expression. In vitro administration of the oxidant, hydrogen peroxide, and the depletion of GSH (using buthionine sulfoximine (BSO)) in 21EM15 lens epithelial cells induced cytokine expression, an effect that was prevented by co-treatment of the cells with N-acetyl-l-cysteine (NAC), a antioxidant. The in vivo and ex vivo induction of cytokine expression by oxidative stress was associated with the expression of markers of epithelial-to-mesenchymal transition (EMT), α-SMA, in lens cells. Given that EMT of lens epithelial cells causes posterior capsule opacification (PCO), we propose that oxidative stress induces cytokine expression, EMT and the development of PCO in a positive feedback loop. Collectively these data indicate that oxidative stress induces inflammation of lens cells which promotes immune surveillance of ocular structures.


Assuntos
Olho/anatomia & histologia , Imunidade Inata , Cristalino/metabolismo , Estresse Oxidativo , Acetilcisteína/farmacologia , Animais , Butionina Sulfoximina/farmacologia , Linhagem Celular , Quimiocina CCL7/genética , Quimiocina CCL7/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Olho/metabolismo , Glutamato-Cisteína Ligase/deficiência , Glutamato-Cisteína Ligase/genética , Cristalino/citologia , Leucócitos/citologia , Leucócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
Appl Radiat Isot ; 182: 110146, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35182934

RESUMO

Knowledge of the energy deposition in different eye components is a critical decision-making to the overall effectivity of ocular melanoma treatment with plaques loaded with low-energy sources. The aim of this study is using the GATE 8.2 Monte Carlo code to calculate the 3D dose distribution in a realistic eye model. At first, we validated the GATE simulation for 125I, 103Pd, and 131Cs seeds by calculating the dose rate constant, radial dose function, and anisotropy function of the three radioactive sources. Then, a 12-mm Collaborative Ocular Melanoma Study (COMS) eye plaque was simulated in the eye phantoms to evaluate dose distribution due to low-energy gamma emitters on the three simulated medium-sized tumors. The findings of this study indicate that the estimated doses received by different eye substructures strongly depend on the source type. The results show that the type of seeds used in the plaque, as well as the size of the eye tumor, have significant effects on the dose deposition in the different structures of the eye and dose deposition uniformity. Moreover, comparing different radionuclides showed that the COMS plaque fully loaded with 103Pd presents a higher dose delivery to the tumor and a lower one to the critical structures for medium-sized tumors, while the plaque fully loaded with 131Cs produces the most uniform dose distribution in the tumor.


Assuntos
Neoplasias Oculares/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Braquiterapia , Radioisótopos de Césio , Olho/anatomia & histologia , Neoplasias Oculares/patologia , Humanos , Radioisótopos do Iodo , Paládio , Radioisótopos
7.
Exp Eye Res ; 216: 108932, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35041822

RESUMO

The purpose of this study was to examine the effects of age, gender and population origin on human globe and corneal dimensions and to explore the relationships between the dimensions. Human post-mortem eyes were obtained in Hyderabad (n = 223; range, 0-85 years) and Miami (n = 486; range, 6-103 years). The eyes were freed of extraneous tissues and globe antero-posterior length (GAPL), mean globe diameter (MGD) (average of horizontal and vertical), and corneal horizontal (HCD) and vertical (VCD) diameters were measured using digital calipers. The relationships of age, gender and population origin with globe and corneal dimensions and the relationships between the dimensions were assessed by bivalent and multiple regression analyses. Globe and cornea dimensions increase asymptotically with age until around the late teens but do not change thereafter. Bivariate and multivariate regression analyses of the >20-year-old eyes showed that population was significantly correlated with GAPL, MGD, HCD and VCD. Male globes and corneas were larger than those from females, but the difference did not appear to be statistically significant. All Hyderabad dimensions were significantly larger than those from the Miami. Neither GAPL nor MGD were correlated with the corneal dimensions. GAPL was significantly correlated with MGD as was HCD with VCD.


Assuntos
Envelhecimento/fisiologia , Biometria/métodos , Córnea/anatomia & histologia , Olho/anatomia & histologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comprimento Axial do Olho/anatomia & histologia , Criança , Pré-Escolar , Córnea/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Doadores de Tecidos
8.
Am J Clin Dermatol ; 23(1): 51-60, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34731450

RESUMO

Psoriasis is a chronic immune-mediated inflammatory skin condition that commonly presents with red, thickened, and scaling plaques. Given the prominent cutaneous manifestations of psoriasis, more subtle ophthalmic findings of the disease may initially go undetected, with the potential for significant ocular morbidity. Associated ocular disease can involve nearly any structure of the eye, with the eyelids most commonly being affected, resulting in relatively common signs and symptoms of ocular surface discomfort. The presence of intraocular inflammation (i.e., uveitis) or retinal involvement carry a heightened risk of vision loss, and are often more difficult to diagnose outside of the ophthalmology clinic. Early detection and treatment of ocular disease can limit morbidity and are critical to the management of these patients, which requires coordination of care between dermatologists and ophthalmologists. The objective of this article was to review the most common ocular conditions that affect psoriatic patients, when to consider referral to an ophthalmologist, and to summarize the adverse ocular effects of current psoriasis treatments.


Assuntos
Oftalmopatias/etiologia , Psoríase/complicações , Fármacos Dermatológicos/efeitos adversos , Olho/anatomia & histologia , Humanos , Fototerapia/efeitos adversos , Psoríase/terapia
9.
J Cataract Refract Surg ; 48(7): 819-825, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34759175

RESUMO

PURPOSE: To compare axial length (AL) measurements obtained by optical biometry (OB) and immersion ultrasound (iUS) to investigate the agreement between the 2 techniques and how to use OB constants for eyes with AL by iUS. SETTING: Multicenter study. DESIGN: Retrospective observational case series. METHODS: Agreement between OB and iUS ALs was investigated in 4 subsets. Also, in a test database, the prediction error (PE) for iUS AL was assessed with 4 methods: (1) data-optimized constants; (2) user group for laser interference biometry (ULIB) constants with iUS biometry; (3) with recalibrated AL; and (4) ULIB A-constant - 0.23. RESULTS: A Combined 1970 eyes were measured with both OB and iUS biometry. OB mean AL was 0.0873 mm longer than iUS AL. The latter was made equivalent to OB ALs with this equation: Recalibrated iUS AL = 1.0228 × iUS AL - 0.4556. In a fifth database (n = 1079) with OB AL measurements only, after AL was artificially shortened by 0.0873 mm, the original A-constant had to be reduced by 0.23 to maintain a zero PE. In a sixth database (n = 127) with iUS AL, the original ULIB A-constant provided the poorest outcomes. Using either recalibrated iUS AL or ULIB A-constant - 0.23 zeroed out the mean PE and achieved the lowest median absolute error. CONCLUSIONS: AL measurements by iUS can be used with ULIB constants for OB by subtracting 0.23 from the A-constant; alternatively, the iUS AL may be recalibrated. The recalibrated iUS AL should be treated as AL measurements obtained by OB. It is longer than iUS AL in long eyes.


Assuntos
Lentes Intraoculares , Refração Ocular , Comprimento Axial do Olho , Biometria/métodos , Olho/anatomia & histologia , Humanos , Imersão , Óptica e Fotônica , Estudos Retrospectivos
10.
Artigo em Inglês | MEDLINE | ID: mdl-34770229

RESUMO

BACKGROUND: Do gender, age, body mass and height influence eye biometrical properties in young adults? METHODS: A total of 155 eyes (92 female, 63 male) of healthy subjects between the ages of 18 and 39 years were included in the study. The subjects' gender and age were recorded, and their body mass, height and biometrical properties of the eyes were measured. RESULTS: The male subjects had significantly thicker and flatter corneas and lower minimal rim-to-disk ratios than the female subjects did. In both genders, age showed strong, negative correlations with anterior chamber depth and pupil diameter and a positive correlation with lens thickness. We also found significant, negative correlations between body height and mass with keratometry measurements, negative correlations between body height and optic disk rim area and rim volume, and positive correlations between body mass and axial length in both genders. CONCLUSIONS: Biometric eye parameters differ among people. In addition to age and gender, which are usually taken into consideration when interpreting ocular biometry findings, we strongly suggest that body height and mass should be also routinely considered when interpreting eye biometry data, as these factors have an impact on ocular biometry.


Assuntos
Biometria , Cristalino , Adolescente , Adulto , Estatura , Estudos Transversais , Olho/anatomia & histologia , Feminino , Humanos , Masculino , Projetos Piloto , Adulto Jovem
12.
Vet Ophthalmol ; 24(5): 533-542, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34554632

RESUMO

PURPOSE: To provide a descriptive investigation about relevant features of the crested caracara's eye (Caracara plancus) and bony orbit, as well as provide data for ophthalmic tests. METHODS: Morphological observations and the following diagnostic tests were performed: Schirmer tear test (STT), conjunctival flora evaluation, corneal touch threshold (CTT), intraocular pressure (IOP), central corneal thickness (CCT), B-mode ocular biometry, palpebral fissure length (PFL), and corneal diameter (CD) in 19 healthy birds, plus two macerated skulls. Not all birds were used for each test. RESULTS: STT: 7.84 ± 3.05 mm/min; CTT: 2.46 ± 1.10 cm; IOP: 19.18 ± 3.07 mmHg; CCT: 0.31 ± 0.02 mm; PFL: 13.32 ± 1.06 mm; CD: 10.26 ± 2.43 mm; Axial globe length: 1.89 ± 0.06 cm; Anterior chamber depth: 0.27 ± 0.06 cm; Lens axial length: 4.55 ± 0.06 cm; Vitreous chamber depth: 1.2 ± 0.07 cm. The most frequent conjunctival bacterial isolates were Corynebacterium sp. (10/23.8%), Staphylococcus sp. (9/21.42%), Streptococcus sp. (7/16.6%), and E. coli (7/16.66%). The large lateral part of the palatine bone likely plays a role in the ventral protection of the globe against the impact of prey. Observed results are generally reflective of increased body mass compared to other Falconiformes, with values approaching those of similar sized Accipitriformes. CONCLUSIONS: These data may help veterinarians recognize peculiar morphologic features and perform a more accurate diagnosis of eye diseases of this avian species.


Assuntos
Oftalmopatias/veterinária , Olho/anatomia & histologia , Falconiformes/anatomia & histologia , Animais , Córnea/fisiologia , Técnicas de Diagnóstico Oftalmológico/veterinária , Olho/microbiologia , Oftalmopatias/diagnóstico , Oftalmopatias/microbiologia , Feminino , Masculino , Fenômenos Fisiológicos Oculares , Órbita/anatomia & histologia , Lágrimas
14.
PLoS One ; 16(9): e0256975, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34499644

RESUMO

Lens and skin fluorescence are related to the systemic accumulation of advanced glycation end products, which is accelerated in diabetes. We have examined lens fluorescence and skin fluorescence in healthy adult twins. The study enrolled twins aged median 59 years from a national population-based registry. Diabetic individuals were excluded from analysis. The interrelatedness between fluorescence parameters and relations between fluorescence and age, current HbA1c and smoking pack years were examined using correlation tests and mixed model linear regression analyses. Broad-sense heritability was analyzed and compared for lens fluorescence, skin fluorescence and HbA1c. Lens fluorescence and skin fluorescence were crudely interrelated (R = 0.38). In linear regression analyses, age explained a larger fraction of the variance in lens fluorescence (R2 = 32%) than in skin fluorescence (R2 = 20%), whereas HbA1c explained smaller variance fractions (R2 = 3% and 8%, respectively) followed by smoking pack years (4% and 3%, respectively). In multivariate analyses, age, HbA1c and smoking pack years combined explained more of the variance in lens fluorescence (R2 = 35%) than in skin fluorescence (R2 = 21%), but the influence of HbA1c on lens fluorescence was not statistically significant (p = .2). Age-adjusted broad-sense heritability was 85% for lens fluorescence, 53% for skin fluorescence and 71% for HbA1c in best fitting heritability models. Both fluorescence parameters increased with age, current glycemia and cumulative smoking. Lens fluorescence was found to be a predominantly heritable trait, whereas skin fluorescence was more influenced by environmental factors and closer related to current glycemia. The results suggest that skin fluorophores have a faster turn-over than lens fluorophores.


Assuntos
Olho/anatomia & histologia , Cristalino/anatomia & histologia , Fenômenos Fisiológicos Oculares/genética , Pele/anatomia & histologia , Pré-Escolar , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Fluorescência , Humanos , Lactente , Cristalino/metabolismo , Masculino , Pessoa de Meia-Idade , Pele/metabolismo , Estudos em Gêmeos como Assunto , Gêmeos Monozigóticos/genética
15.
PLoS One ; 16(8): e0255363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34347814

RESUMO

The standard histological processing procedure, which produces excellent staining of sections for most tissues, fails to yield satisfactory results in adult mouse orbits or eyeballs. Here, we show that a protocol using tissue block staining and domestic adhesive tapes resulted in qualified integral serial cryo-sections of whole orbits or eyeballs, and the fine structures were well preserved. The histological processing protocol comprises paraformaldehyde fixation, ethylenediaminetetraacetic acid decalcification, tissue block staining with hematoxylin and eosin, embedding, adhesive tape aided sectioning, and water-soluble mounting. This protocol was proved to be the best in comparison with seven other related existing histological traditional or non-traditional processing methods, according to the staining slice quality. We observed a hundred percent success rate in sectioning, collection, and mounting with this method. The reproducibility tested on qualified section success rates and slice quality scores confirmed that the technique is reliable. The feasibility of the method to detect target molecules in orbits was verified by successful trial tests on block immunostaining and adhesive tape-aided sectioning. Application of this protocol in joints, brains, and so on,-the challenging integral sectioning tissues, also generated high-quality histological staining sections.


Assuntos
Olho/anatomia & histologia , Órbita/anatomia & histologia , Preservação de Tecido/instrumentação , Animais , Criopreservação , Estudos de Viabilidade , Feminino , Camundongos , Microtomia , Coloração e Rotulagem , Fita Cirúrgica , Inclusão do Tecido , Fixação de Tecidos , Preservação de Tecido/métodos
16.
Nat Biomed Eng ; 5(7): 726-736, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34253888

RESUMO

Clinical systems for optical coherence tomography (OCT) are used routinely to diagnose and monitor patients with a range of ocular diseases. They are large tabletop instruments operated by trained staff, and require mechanical stabilization of the head of the patient for positioning and motion reduction. Here we report the development and performance of a robot-mounted OCT scanner for the autonomous contactless imaging, at safe distances, of the eyes of freestanding individuals without the need for operator intervention or head stabilization. The scanner uses robotic positioning to align itself with the eye to be imaged, as well as optical active scanning to locate the pupil and to attenuate physiological eye motion. We show that the scanner enables the acquisition of OCT volumetric datasets, comparable in quality to those of clinical tabletop systems, that resolve key anatomic structures relevant for the management of common eye conditions. Robotic OCT scanners may enable the diagnosis and monitoring of patients with eye conditions in non-specialist clinics.


Assuntos
Oftalmopatias/diagnóstico , Tomografia de Coerência Óptica/métodos , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Oftalmopatias/diagnóstico por imagem , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Retina/diagnóstico por imagem , Robótica , Tomografia de Coerência Óptica/instrumentação
17.
Sci Rep ; 11(1): 14590, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272413

RESUMO

In retinoblastoma, accurate segmentation of ocular structure and tumor tissue is important when working towards personalized treatment. This retrospective study serves to evaluate the performance of multi-view convolutional neural networks (MV-CNNs) for automated eye and tumor segmentation on MRI in retinoblastoma patients. Forty retinoblastoma and 20 healthy-eyes from 30 patients were included in a train/test (N = 29 retinoblastoma-, 17 healthy-eyes) and independent validation (N = 11 retinoblastoma-, 3 healthy-eyes) set. Imaging was done using 3.0 T Fast Imaging Employing Steady-state Acquisition (FIESTA), T2-weighted and contrast-enhanced T1-weighted sequences. Sclera, vitreous humour, lens, retinal detachment and tumor were manually delineated on FIESTA images to serve as a reference standard. Volumetric and spatial performance were assessed by calculating intra-class correlation (ICC) and dice similarity coefficient (DSC). Additionally, the effects of multi-scale, sequences and data augmentation were explored. Optimal performance was obtained by using a three-level pyramid MV-CNN with FIESTA, T2 and T1c sequences and data augmentation. Eye and tumor volumetric ICC were 0.997 and 0.996, respectively. Median [Interquartile range] DSC for eye, sclera, vitreous, lens, retinal detachment and tumor were 0.965 [0.950-0.975], 0.847 [0.782-0.893], 0.975 [0.930-0.986], 0.909 [0.847-0.951], 0.828 [0.458-0.962] and 0.914 [0.852-0.958], respectively. MV-CNN can be used to obtain accurate ocular structure and tumor segmentations in retinoblastoma.


Assuntos
Olho/anatomia & histologia , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Descolamento Retiniano/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Neoplasias da Retina/diagnóstico por imagem , Retinoblastoma/diagnóstico por imagem , Automação/métodos , Criança , Pré-Escolar , Aprendizado Profundo , Feminino , Humanos , Lactente , Recém-Nascido , Cristalino/anatomia & histologia , Imageamento por Ressonância Magnética , Masculino , Redes Neurais de Computação , Estudos Retrospectivos , Esclera/anatomia & histologia , Corpo Vítreo/anatomia & histologia
18.
J Biophotonics ; 14(10): e202100021, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34159745

RESUMO

In order to meet the demands of myopia prevention, as well as the increasing needs of measurement for refractive and cataract operations in China, a new axial length (AL) measurement system combining an improved Twyman-Green interferometer with digital signal processing has been established. The ALs of 33 eyes of different optical refractive subjects (-8.50 ~ 0.50 D) were measured with the New AL and intraocular lens (IOL) master. The repeatability of measurements with the New AL was assessed using coefficient of variation (CoV) and intra-group correlation coefficient (ICC). Comparison, correlation, linear regression and agreement of AL between devices were analyzed. There was good repeatability (CoV = 0.0617%, ICC = 0.9999) with the New AL and great agreement has been obtained with both devices. These show that the New AL is capable of providing precise AL values over the normal AL range compared to the IOL master, and indicate that the New AL developed can be used for routine clinical AL measurements.


Assuntos
Biometria , Olho , Interferometria , Biometria/métodos , China , Olho/anatomia & histologia , Humanos , Lentes Intraoculares , Óptica e Fotônica , Retinoscopia
19.
Appl Opt ; 60(17): 5227-5235, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143092

RESUMO

In this paper, we present the imaging formation process of the piecewise mirror eyes of the deep-sea spookfish, which has a strange combination of refractive and reflective eyes. The biological reflective eye structure is formulated to the curved surface's flat mirror array. Zemax is utilized to evaluate optical features such as the modulation transfer function, distortion, and imaging performances. However, the natural images are highly distorted, and the resolution is lower than expected. Therefore, we increase the number of piecewise mirrors of the fisheye to see higher quality images, which can be improved entirely by the mirror shapes. Finally, the fisheye's imaging analysis reveals the deep-sea creature's resolution limit and also shows the possibility of artificial and biomimetic camera applications.


Assuntos
Olho/anatomia & histologia , Peixes/anatomia & histologia , Imagem Óptica/instrumentação , Animais , Biomimética , Desenho de Equipamento , Modelos Teóricos , Oceanos e Mares , Fenômenos Ópticos , Visão Ocular/fisiologia
20.
Exp Eye Res ; 209: 108653, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34097905

RESUMO

It is well known that human crystalline lens shape, dimensions and optical properties change throughout life and influence whole eye refraction. However, it is not clear if lens properties are associated with other ocular parameters. The purpose of the present study was to investigate the relationship of corneal and external globe dimensions with adult lens diameter (LD), lens thickness (LT) and lens power (LP) in order to determine if external factors influence lens properties. Postmortem human eyes (n = 66, age = 20-78 years) were obtained from the Ramayamma International Eye Bank, Hyderabad, India. Globe antero-posterior length (GAPL) and mean (average of horizontal and vertical) diameters of cornea (MCD) and globe (MGD) were measured using digital calipers. Eyes were dissected to produce ocular structures that contain the lens maintained in its accommodating framework, including intact zonules, ciliary body and sections of sclera. Specimens were mounted in a mechanical lens stretching system. LD, LT and LP were measured using high magnification retro-illumination photography, slit illumination photography and Scheiner principle-based optical system respectively in the unstretched (accommodated) state. Relationships between external globe and corneal dimensions and LD, LT or LP were assessed by multiple regression analysis. Age (0.012 ± 0.003 mm/year; p<0.001) and GAPL (0.185 ± 0.045 mm/mm; p<0.001) were significant (p<0.0001) predictors of LD. After adjusting for age-related increases, LD appears to be positively correlated with GAPL. Age (0.010 ± 0.004 mm/year; p = 0.009) and GAPL (-0.143 ± 0.060 mm/mm; p = 0.02) were significant (p = 0.001) predictors of LT. After adjusting for the age-related increase, LT appears to be negatively correlated with GAPL. Only age was a significant predictor of LP (-0.26 ± 0.04 D/year; p<0.001). The results suggest that, apart from aging, lens diameter and thickness are dependent on the anteroposterior length of the eye globe. Lens power is not influenced by globe dimensions.


Assuntos
Acomodação Ocular/fisiologia , Envelhecimento/fisiologia , Biometria/métodos , Córnea/anatomia & histologia , Olho/anatomia & histologia , Cristalino/anatomia & histologia , Refração Ocular/fisiologia , Adulto , Idoso , Córnea/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Adulto Jovem
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