Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
J Cataract Refract Surg ; 50(5): 492-497, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38237070

RESUMO

PURPOSE: To investigate the difference between the segmented axial length (AL) and the composite AL on a swept-source optical coherence tomography biometer and to evaluate the subsequent effects on artificial intelligence intraocular lens (IOL) power calculations: the Kane and Hill-RBF 3.0 formulas compared with established vergence formulas. SETTING: National Hospital Organization, Tokyo Medical Center, Japan. DESIGN: Retrospective case series. METHODS: Consecutive patients undergoing cataract surgery with a single-piece IOL were reviewed. The prediction accuracy of the Barrett Universal II, Haigis, Hill-RBF 3.0, Hoffer Q, Holladay 1, Kane, and SRK/T formulas based on 2 ALs were compared for each formula. The heteroscedastic test was used with the SD of prediction errors as the endpoint for formula performance. RESULTS: The study included 145 eyes of 145 patients. The segmented AL (24.83 ± 1.89) was significantly shorter than the composite AL (24.88 ± 1.96, P < .001). Bland-Altman analysis revealed a negative proportional bias for the differences between the segmented AL and the composite AL. The SD values obtained by Hoffer Q, Holladay 1, and SRK/T formulas based on the segmented AL (0.52 diopters [D], 0.54 D, and 0.50 D, respectively) were significantly lower than those based on the composite AL (0.57 D, 0.60 D, and 0.52 D, respectively, P < .01). CONCLUSIONS: The segmented ALs were longer in short eyes and shorter in long eyes than the composite ALs. The refractive accuracy can be improved in the Hoffer Q, Holladay 1, and SRK/T formulas by changing the composite ALs to the segmented ALs.


Assuntos
Comprimento Axial do Olho , Biometria , Lentes Intraoculares , Óptica e Fotônica , Facoemulsificação , Refração Ocular , Tomografia de Coerência Óptica , Humanos , Comprimento Axial do Olho/patologia , Comprimento Axial do Olho/diagnóstico por imagem , Estudos Retrospectivos , Biometria/métodos , Masculino , Feminino , Tomografia de Coerência Óptica/métodos , Refração Ocular/fisiologia , Implante de Lente Intraocular , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Acuidade Visual/fisiologia , Pseudofacia/fisiopatologia
2.
J Clin Med ; 12(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38002573

RESUMO

PURPOSE: To evaluate the performance of traditional vergence formulas with segmented axial length (AL) compared to traditional composite AL in extremely long eyes, and to determine whether the segmented AL can be extended to the new-generation formulas, including the Barrett Universal II, Emmetropia Verifying Optical 2.0 (EVO2), Hill-RBF 3.0 (Hill3), Kane, and Ladas Super formula (LSF) formulas in extremely long eyes. SETTING: National Hospital. Organization, Tokyo Medical Center, Japan. DESIGN: Retrospective case series. METHODS: Consecutive patients who underwent uncomplicated cataract surgery implanted with a three-piece intraocular lens between December 2015 and March 2021 were retrospectively reviewed. The composite AL was measured with a swept-source optical coherence tomography (SS-OCT) biometer using a mean refractive index. The segmented AL was calculated by summing the geometric lengths of the ocular segments (cornea, aqueous, lens, and vitreous) using multiple specific refractive indices based on the data obtained by the SS-OCT-based biometer. When refraction was measured at three months postoperatively, the median absolute errors (MedAEs) were calculated with two ALs for each formula. RESULTS: The study included 31 eyes of 22 patients. The segmented AL (30.45 ± 1.23 mm) was significantly shorter than the composite AL (30.71 ± 1.28 mm, p < 0.001). The MedAEs were significantly reduced when using segmented AL for SRK/T, Haigis, Hill3, and LSF, compared to those obtained using composite AL (0.38 vs. 0.62, 0.48 vs. 0.79, 0.50 vs. 0.90, 0.34 vs. 0.61, p < 0.001 for all formulas, respectively). On the contrary, the MedAE obtained by Kane with segmented AL was significantly worse compared to the one with composite AL (0.35 vs. 0.27, p = 0.03). CONCLUSION: In extremely high myopic eyes, the segmented AL improves the performance of SRK/T, Haigis, Hill3, and LSF formulas compared to the composite AL, while the segmented AL worsens the prediction accuracy of the Kane formula.

3.
PLoS One ; 17(8): e0273431, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36040874

RESUMO

PURPOSE: To compare the change in intraocular lens (IOL) axial movement, corneal power, and postoperative refraction of eyes implanted with two different single-piece, open loop, acrylic foldable IOLs with planar-haptic design: one IOL with hinges vs. one IOL without hinges. The role of IOL axial movement on short-term refractive shift after cataract surgery was also evaluated. METHODS: This retrospective comparative study enrolled consecutive patients who had phacoemulsification with aspheric IOL implantation. The IOL depth (the distance from corneal endothelium to IOL surface) and corneal power were measured via anterior-segment optical coherence tomography at 4 days and 1 month postoperatively. The changes in axial movement of the IOL, corneal power, and manifest refractive spherical equivalent (MRSE) were compared among groups, and the correlations between each lens were evaluated. RESULTS: IOL with hinges was implanted in 42 eyes of 42 patients and IOL without hinges was implanted in 42 eyes of 42 patients. The change in axial movement between 4 days and 1 month was significantly smaller in the IOL with hinges group than in the IOL without hinges group (p < 0.001). The axial movement of IOL with hinges did not correlate with the MRSE change; however, the forward shift of IOL without hinges correlated with the myopic refractive change (Pearson r = 0.62, p < 0.001). CONCLUSION: The postoperative axial movement of IOL was more stable in the IOL with hinges group than the IOL without hinges group between 4 days and 1 month after cataract surgery. Even though the two study IOLs with planar-haptic design are made of similar acrylic materials, other characteristics such as hinge structure may affect IOL stability in the bag.


Assuntos
Catarata , Lentes Intraoculares , Facoemulsificação , Humanos , Implante de Lente Intraocular/métodos , Facoemulsificação/métodos , Estudos Prospectivos , Desenho de Prótese , Refração Ocular , Estudos Retrospectivos
4.
J Cataract Refract Surg ; 48(11): 1305-1311, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642086

RESUMO

PURPOSE: To evaluate the performance of a new formula of intraocular lens (IOL) power calculation (the O formula) based on ray tracing without commonly used parameters, including ultrasound-compatible axial length, keratometry readings, and A-constant. SETTING: Tokyo Medical Center, Tokyo, Japan. DESIGN: Retrospective consecutive case series. METHODS: 423 eyes (423 patients) implanted with a single-piece, L-loop, acrylic IOL were enrolled. All biometric data for the O formula were obtained by anterior segment swept-source optical coherence tomography (SS-OCT) and SS-OCT-based biometer. The performance of the O formula was compared with those of the Barrett Universal II (BUII) and Kane formulas at 1 month postoperatively. Statistical analysis was applied according to a heteroscedastic test with SD of prediction errors as the main parameter for formula performance. RESULTS: The SD of the O formula (0.426) was statistically significantly lower than that of the BUII formula (0.464, P = .034) but not statistically significantly different from that of the Kane formula (0.433, P = .601). The percentages of patients with refractive prediction errors within ±0.50 diopter (D) and ±1.00 D of the O, BUII, and Kane formulas were 75.4% and 98.6%, 77.1% and 97.9%, and 76.6% and 98.1%, respectively. CONCLUSIONS: The O formula, based on ray tracing using SS-OCT-based devices, is one of the promising approaches for IOL power calculation, although additional larger scale studies are needed. It may be used as an alternative in IOL power calculation because of its independence from commonly used parameters.


Assuntos
Lentes Intraoculares , Facoemulsificação , Erros de Refração , Humanos , Facoemulsificação/métodos , Estudos Retrospectivos , Biometria/métodos , Óptica e Fotônica , Refração Ocular , Comprimento Axial do Olho
5.
Appl Opt ; 60(13): 3689-3698, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983301

RESUMO

In recent years, with the development of precise lathe-cutting equipment, special shaped contact lenses (CL) have been crafted. However, while it is possible to manufacture such a lens, its shape evaluation has not been well-established. We conducted a basic optical experiment using special lenses to measure a spherical lens and nonspherical mold. As the measurement sample, a metal ball, special CL, and a toric-shaped mold were adopted. In order to accurately measure those real shapes, we proposed an algorithm in which the probe light is vertically incident to the sample surface within a numerical aperture of the optical probe. For this algorithm, we developed the specialized time-domain optical coherence tomography (TD-OCT), which was designed to conduct circular scanning while maintaining vertical incidence by driving a two-axis (vertical and horizontal) micro-electromechanical system mirror with a phase difference of 90°. The shape, thickness distribution, and curvature radii of both front and back surfaces of a CL were estimated with this OCT signal analysis and sphere fitting. The shape and curvature radius were evaluated by using the simulated data under the same experimental conditions. They were sufficiently accurate based on the resolution of this OCT. Also, a toric-shaped mold was evaluated by comparing the relationship between each coordinate and intensity of the interference signal. As a result, it is confirmed that the experimental result and the simulated matched well.

6.
Appl Opt ; 59(28): 9051-9059, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104595

RESUMO

The optical measurement algorithm for the real front and back surfaces of contact lenses from their center to periphery accurately and simultaneously is proposed. It is an algorithm that makes light incident vertically along the curved surfaces of contact lenses under the condition that the difference of curvature radii between the front and back surfaces is small enough within the NA of the optical probe. For this purpose, we adopted time-domain optical coherence tomography (OCT) with translation and rotation mechanisms. The shape, thickness distribution, and curvature radii of both surfaces were estimated with OCT signal analysis and circular approximation. The measured results were compared with the designed values and the measured data from a conventional shape measurement device. The curved shape of both surfaces and thickness were well matched with the designed values from lens center to periphery. In a curvature radius of the front surface, there was a proportional bias with a limit of agreement of -0.77% to -2.09%, and the correlation coefficient was 0.57. On the back surface, there was no systematic bias, and minimal detectable change was 0.178 mm, in a range of 95% confidential interval. The proposed algorithm well visualized the real shape and optical characteristics of the contact lens with enough accuracy to the design.

7.
J Cataract Refract Surg ; 46(5): 710-715, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358265

RESUMO

PURPOSE: To compare the changes in axial length (AL) obtained after cataract surgery by partial coherence interferometry (PCI), swept-source optical coherence tomography with the composite method (SS-OCT/CM), and SS-OCT with the segmental method (SS-OCT/SM). SETTING: National Hospital Organization, Tokyo Medical Center, Japan. DESIGN: Retrospective case series. METHODS: AL was measured preoperatively and 1 month postoperatively by PCI, SS-OCT/CM, and SS-OCT/SM. RESULTS: Two hundred sixty-eight eyes in 139 patients who underwent cataract surgery were included. The mean ALs measured by PCI and SS-OCT/CM decreased significantly from 24.14 ± 1.58 to 24.05 ± 1.58 mm (P < .0001) and from 24.15 ± 1.58 to 24.05 ± 1.59 mm (P < .0001), respectively. The mean differences between the preoperative and postoperative AL were 0.083 ± 0.044 mm (PCI) and 0.096 ± 0.045 mm (SS-OCT/CM), respectively; Bland-Altman analysis revealed fixed bias between the preoperative and postoperative values. The mean preoperative and postoperative ALs measured by SS-OCT/SM were 24.12 ± 1.54 and 24.12 ± 1.54 mm, respectively (P = 0.97). The mean difference between the preoperative and postoperative ALs was 0.00 ± 0.03 mm on SS-OCT/SM; Bland-Altman analysis indicated good agreement between these values. CONCLUSIONS: The difference between preoperative and postoperative ALs is less with SS-OCT/SM than with PCI or SS-OCT/CM. Assuming that AL is not altered by cataract surgery, AL measurement is more accurate by SS-OCT/SM than by PCI or SS-OCT/CM.


Assuntos
Biometria , Catarata , Comprimento Axial do Olho , Humanos , Japão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia de Coerência Óptica
8.
Sci Rep ; 10(1): 4474, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161358

RESUMO

This study compared the optical axial length (AL) obtained by composite and segmental methods using swept-source optical coherence tomography (SS-OCT) devices, and demonstrated its effects on the post-operative refractive errors (RE) one month after cataract surgery. Conventional AL measured with the composite method used the mean refractive index. The segmented-AL method used individual refractive indices for each ocular medium. The composite AL (24.52 ± 2.03 mm) was significantly longer (P < 0.001) than the segmented AL (24.49 ± 1.97 mm) among a total of 374 eyes of 374 patients. Bland-Altman analysis revealed a negative proportional bias for the differences between composite and segmented ALs. Although there was no significant difference in the RE obtained by the composite and segmental methods (0.42 ± 0.38 D vs 0.41 ± 0.36 D, respectively, P = 0.35), subgroup analysis of extremely long eyes implanted with a low power intraocular lens indicated that predicted RE was significantly smaller with the segmental method (0.45 ± 0.86 D) than that with the composite method (0.80 ± 0.86 D, P < 0.001). Segmented AL with SS-OCT is more accurate than composite AL in eyes with extremely long AL and can improve post-operative hyperopic shifts in such eyes.

9.
Sci Rep ; 7(1): 14523, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-29109514

RESUMO

Myopia is increasing worldwide. Although the exact etiology of myopia is unknown, outdoor activity is one of the most important environmental factors for myopia control. We previously reported that violet light (VL, 360-400 nm wavelength), which is abundant in the outdoor environment, suppressed myopia progression for individuals under 20 years of age. However, whether VL is also effective for adult high myopia, which can be sight-threatening, has remained unknown. To investigate the influence of VL for adult myopia, we retrospectively compared the myopic progression and the axial length elongation over five years in adult high myopic patients over 25 years of age after two types (non-VL transmitting and VL transmitting) of phakic intraocular lens (pIOL) implantation. We found that high myopic patients with the non-VL transmitting pIOLs implanted are almost two times more myopic in the change of refraction and four times longer in the change of axial length, compared to those implanted with the VL transmitting pIOLs. This result indicated that the VL transmitting pIOL suppressed myopia progression and axial length elongation compared with the non-VL transmitting one. In conclusion, our study showed the VL possibly has an anti-myopia effect for human adults with high myopia.


Assuntos
Luz , Miopia/epidemiologia , Adulto , Astigmatismo/epidemiologia , Astigmatismo/fisiopatologia , Astigmatismo/prevenção & controle , Astigmatismo/cirurgia , Progressão da Doença , Humanos , Implante de Lente Intraocular , Lentes Intraoculares , Pessoa de Meia-Idade , Miopia/fisiopatologia , Miopia/prevenção & controle , Miopia/cirurgia , Fatores de Proteção , Exposição à Radiação , Estudos Retrospectivos
10.
Ophthalmology ; 124(6): e54, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28528841
11.
EBioMedicine ; 15: 210-219, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28063778

RESUMO

Prevalence of myopia is increasing worldwide. Outdoor activity is one of the most important environmental factors for myopia control. Here we show that violet light (VL, 360-400nm wavelength) suppresses myopia progression. First, we confirmed that VL suppressed the axial length (AL) elongation in the chick myopia model. Expression microarray analyses revealed that myopia suppressive gene EGR1 was upregulated by VL exposure. VL exposure induced significantly higher upregulation of EGR1 in chick chorioretinal tissues than blue light under the same conditions. Next, we conducted clinical research retrospectively to compare the AL elongation among myopic children who wore eyeglasses (VL blocked) and two types of contact lenses (partially VL blocked and VL transmitting). The data showed the VL transmitting contact lenses suppressed myopia progression most. These results suggest that VL is one of the important outdoor environmental factors for myopia control. Since VL is apt to be excluded from our modern society due to the excessive UV protection, VL exposure can be a preventive strategy against myopia progression.


Assuntos
Luz , Miopia/diagnóstico , Miopia/terapia , Fototerapia , Adolescente , Animais , Linhagem Celular , Galinhas , Criança , Modelos Animais de Doenças , Progressão da Doença , Óculos , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Masculino , Miopia/etiologia , Refração Ocular , Luz Solar , Resultado do Tratamento , Raios Ultravioleta
12.
Ophthalmology ; 123(12): 2474-2480, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27769585

RESUMO

PURPOSE: To evaluate the accuracy of a new formula for predicting postoperative anterior chamber depth (ACD) with preoperative angle-to-angle (ATA) depth using anterior segment (AS) optical coherence tomography (OCT) and to compare it with established methods. DESIGN: Retrospective consecutive case series. PARTICIPANTS: Three hundred four eyes (276 patients) implanted with acrylic intraocular lenses (IOLs) were divided randomly into a training set (152 eyes) and a validation set (152 eyes). METHODS: Based on the training set data, the postoperative ACD measured 1 month after surgery was analyzed via multiple linear regression analysis with 5 preoperatively measured variables: ATA depth, ATA width, preoperative ACD measured with AS OCT, axial length (AL), and corneal power. A new regression formula for predicting postoperative ACD was developed using the results of the stepwise analysis. In the validation set data, the coefficients of determination (R2) between the measured postoperative ACD and the predicted postoperative ACD obtained using the new formula were compared with those obtained using the Sanders-Retzlaff-Kraff theoretic (SRK/T) and Haigis formulas. The absolute prediction errors were compared with each formula. MAIN OUTCOME MEASURES: Postoperative ACD, median absolute prediction error of postoperative ACD, and ocular biometric parameters. RESULTS: In the training set, ATA depth yielded the highest standard partial regression coefficient value, indicating that ATA depth is the most effective parameter for predicting postoperative ACD. The new regression formula was developed with 3 variables; ATA depth, preoperative ACD, and AL. In the validation set, the postoperative ACDs of the new formula, the SRK/T formula, and Haigis formula were predicted with R2 of 0.71, 0.36, and 0.55, respectively, and the medians of the absolute prediction errors were 0.10 mm, 0.65 mm, and 0.30 mm, respectively. The absolute prediction error with the new formula was significantly smaller than those obtained with the SRK/T and Haigis formulas (P < 0.0001). CONCLUSIONS: The new formula with 3 preoperative parameters-ATA depth, preoperative ACD, and AL-predicted postoperative ACD more accurately than the SRK/T and Haigis formulas. It may be possible to improve the accuracy of IOL power calculation using an improved postoperative ACD prediction with the ATA depth measured by AS OCT.


Assuntos
Algoritmos , Câmara Anterior/patologia , Lentes Intraoculares , Tomografia de Coerência Óptica/métodos , Idoso , Idoso de 80 Anos ou mais , Câmara Anterior/diagnóstico por imagem , Biometria/métodos , Extração de Catarata , Corpo Ciliar/diagnóstico por imagem , Corpo Ciliar/patologia , Feminino , Humanos , Iris/diagnóstico por imagem , Iris/patologia , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Óptica e Fotônica , Período Pós-Operatório , Análise de Regressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Malha Trabecular/diagnóstico por imagem , Malha Trabecular/patologia
13.
Cornea ; 34 Suppl 11: S128-35, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26448170

RESUMO

An understanding of corneal optics is important to optimize the visual outcome after eye surgery. Recent advances in the surgical techniques of lamellar keratoplasty have changed the strategies used for corneal transplantation. Lamellar keratoplasty has the advantage of having a lower rate of graft rejection, superior biomechanical properties, and reduced higher-order aberrations (HOAs) compared with penetrating keratoplasty; thus, the use of lamellar keratoplasty has increased over the last 15 years. However, some patients have poor postoperative visual acuity despite a clear cornea, and the reasons for the poor visual outcome are poorly understood. By combining corneal imaging technologies and the latest optical software, we proposed the concept of "parallelism of anterior and posterior surfaces in lamellar keratoplasty." In physiologically normal eyes, in which the anterior and posterior surfaces are parallel to each other, the posterior surface of the cornea compensates the HOAs of the anterior surface, and this is also true in eyes after penetrating keratoplasty. However, after lamellar keratoplasty, in which the anterior and posterior surfaces are independent and not parallel, irregularities in the posterior surface increase the HOAs of the anterior surface. This article introduces this concept to enhance our understanding of visual optics in eyes after penetrating and lamellar keratoplasties and how to apply this concept to surgery to improve and optimize patient visual outcomes.


Assuntos
Aberrações de Frente de Onda da Córnea/etiologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Ceratoplastia Penetrante/efeitos adversos , Complicações Pós-Operatórias/etiologia , Topografia da Córnea , Aberrações de Frente de Onda da Córnea/fisiopatologia , Humanos , Complicações Pós-Operatórias/fisiopatologia , Período Pós-Operatório , Acuidade Visual/fisiologia
14.
J Cataract Refract Surg ; 40(7): 1182-91, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24957437

RESUMO

PURPOSE: To evaluate the quality of the image of a grating target placed in a model eye and viewed through a small-aperture corneal inlay. SETTING: Kyorin Eye Center, Tokyo, Japan. DESIGN: Experimental study. METHODS: A Kamra corneal inlay was placed on the anterior surface of a fluid-filled model eye, and a United States Air Force target and a calibrated scale were placed on the inner surface of the model eye. With a flat contact lens or a contact or noncontact wide-angle viewing system, the contrast of the grating images and the field of view through the inlay were compared with those without the inlay. RESULTS: A blurred dark ring was observed with the flat contact lens and MiniQuad wide-viewing contact lens in the model eye with the inlay. The contrast of the gratings was significantly decreased at 16 cycles/mm (P=.028), 32 cycles/mm (P=.046), and 64 cycles/mm (P=.015). With the Resight noncontact wide-angle viewing system, the field of view was reduced from 62 degrees to 32 degrees when the front lens was at 7.0 mm and slightly reduced from 75 degrees to 62 degrees at 5.0 mm with the inlay. CONCLUSIONS: The contrast of grating images observed through the inlay was significantly reduced when viewed with the flat contact lens. The field of view through the wide-angle viewing system was also altered. However, the noncontact wide-angle viewing system may be recommended for vitreous surgeries in eyes with the inlay by adjusting the distance of the front lens from the cornea. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Sensibilidades de Contraste/fisiologia , Substância Própria/cirurgia , Modelos Anatômicos , Próteses e Implantes , Campos Visuais/fisiologia , Percepção Visual/fisiologia , Humanos , Polivinil , Implantação de Prótese
16.
Acta Ophthalmol ; 91(7): e561-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23910384

RESUMO

PURPOSE: To try to recreate the images reported by patients during vitreous surgery in a model eye. METHODS: A fluid-filled model eye with a posterior frosted translucent surface which corresponded to the retina was used. Three holes were made in the model eye through which an endoillumination pipe and intraocular forceps could be inserted. A thin plastic sheet simulating an epiretinal membrane and an intraocular lens (IOL) simulating a dislocated IOL were placed on the retina. The images falling on the posterior surface were photographed from the rear. The images seen through the surgical microscope were also recorded. RESULTS: The images from the rear were mirror images of those seen through the surgical microscope. Intraocular instruments were seen as black shafts from the rear. When the plastic sheet was picked up, the tip of the forceps was seen more sharply on the posterior surface. The images of the dislocated IOL from the posterior were similar to that seen through the surgical microscope, including the yellow optics and blue haptics. CONCLUSION: Intravitreal objects can form images on the surface of a model eye. Objects located closer to the surface are seen more sharply, and the colour of the objects can be identified.


Assuntos
Modelos Anatômicos , Retina/fisiologia , Visão Intraocular/fisiologia , Visão Ocular/fisiologia , Corpo Vítreo , Migração do Implante de Lente Intraocular/cirurgia , Membrana Epirretiniana/cirurgia , Humanos , Vitrectomia
17.
Graefes Arch Clin Exp Ophthalmol ; 251(10): 2451-61, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23760671

RESUMO

BACKGROUND: To investigate the peripheral optical quality and its relationship with axial elongation, myopic progression in Japanese children. METHODS: Twenty-nine Japanese children, ages 10 to 12 years old, with baseline refraction from +0.75 D to -5.5 D, were included and followed for 9 months. The central and peripheral point spread functions (PSFs; 0°, 10°, 20°, 30° nasally) were obtained at 0.25 D steps around ±2.5 D of best-focus PSF (BF-PSF) using double-pass PSF system. Modulation transfer function (MTF) area of the BF-PSF was calculated from BF-PSF to represent the peripheral optical quality. Relative peripheral defocus (RPD), the refraction of anterior/posterior focal lines, MTF area, and their correlations with myopia progression were analyzed. RESULTS: The average refractive change in 9 months was -0.5 ± 0.8 D. The change in axial length was significantly positively correlated with the amount of myopic progression (P = 0.0058) and RPD (P = 0.0007, 0.0036 and 0.0040, at 10°, 20°, 30° respectively) at the initial visit, but did not correlate with the peripheral MTF area. Myopic progression of more than 0.5 D with axial elongation was observed in seven children (MP group). The RPDs at 20° and 30° in the MP group were significantly more hyperopic than in the non-MP group (P = 0.002 and 0.007), whereas there was no significant difference in axial length, and central and peripheral MTF area between the MP and non-MP groups. MP group had more hyperopic focal lines compared with non-MP group at 20° and 30°. CONCLUSION: These results suggest that the progression of axial myopia in children is associated with hyperopic RPD and refraction of focal lines, not with peripheral optical quality.


Assuntos
Comprimento Axial do Olho/patologia , Miopia/fisiopatologia , Retina/fisiologia , Visão Binocular/fisiologia , Criança , Progressão da Doença , Feminino , Humanos , Hiperopia/fisiopatologia , Masculino , Estudos Prospectivos , Refração Ocular/fisiologia
18.
Am J Ophthalmol ; 155(2): 243-252.e1, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23036568

RESUMO

PURPOSE: To evaluate the quality of an image of a grating target placed in a model eye and viewed through implanted toric intraocular lenses (IOLs). DESIGN: Laboratory investigation. METHODS: Toric IOLs, SN6AT5 with a cylinder power of 3.0 diopters (3.0 D, Alcon), ST6AT9 (6.0 D, Alcon), 311T5 (3.0 D, HOYA), or 311T9 (6.0 D, HOYA), were placed in a fluid-filled model eye. A United States Air Force test target was placed internally on the posterior surface of the model eye. A flat contact lens or a wide-angle contact lens was placed on the cornea. The contrast and length of the grating targets perpendicular (vertical) or parallel (horizontal) to the flat meridian of the toric IOL were compared with those obtained through aspheric IOLs. RESULTS: The contrast of the targets viewed through the flat contact lens and toric IOLs in the vertical direction was significantly lower than that viewed through the aspheric IOL at 16 cycle/mm (SN6AT9, P=.002; SN6AT5, P=.028; 311T9, P=.002; 311T5, P =.011) but not with the wide-angle viewing lens at 16, 32, and 64 cycle/mm. The vertical length of the target with a flat contact lens was longer and the horizontal length was shorter than that through the aspheric IOL by 1% to 3% with the SN6AT5 and 311T5 IOLs and by 3% to 5% with the SN6AT9 and 311T9 IOLs. However, the vertical and horizontal lengths were not significantly different through the wide-viewing lens. CONCLUSION: Toric IOLs affect the contrast of a grating target viewed through a flat contact lens but not through a wide-angle viewing lens. The wide-angle viewing system is not influenced by cylindrical aberrations.


Assuntos
Sensibilidades de Contraste/fisiologia , Lentes Intraoculares , Modelos Biológicos , Retina/fisiologia , Aberrometria , Astigmatismo/cirurgia , Lentes de Contato , Percepção de Profundidade/fisiologia , Humanos , Implante de Lente Intraocular , Acuidade Visual/fisiologia
19.
Ophthalmologica ; 228(3): 174-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22487898

RESUMO

AIMS: It was the aim of this study to measure spectral transmission of the human crystalline lens in situ. METHOD: The crystalline lens was illuminated by one of four light-emitting diodes of different colors. The relative spectral transmittance of the human crystalline lens was measured with the Purkinje-Sanson mirror images over a wide range of ages. RESULT: The study evaluated 36 crystalline lenses of 28 subjects aged 21-76 years. There was a significant correlation between the age and spectral transmittance for blue light. CONCLUSION: Spectral transmittance of the crystalline lens in situ could be measured with Purkinje-Sanson mirror images.


Assuntos
Envelhecimento/fisiologia , Cristalino/fisiologia , Cristalino/efeitos da radiação , Luz , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Midriáticos/administração & dosagem , Fotografação/instrumentação , Pupila/efeitos dos fármacos , Refração Ocular/efeitos da radiação , Análise Espectral , Acuidade Visual/fisiologia , Adulto Jovem
20.
Clin Ophthalmol ; 5: 1701-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22205829

RESUMO

BACKGROUND: The purpose of this study was to evaluate the correlation between contrast sensitivity and calculated higher-order aberrations based on individual natural pupil diameter after cataract surgery. METHODS: This prospective study included 120 eyes from 92 patients who were randomized to receive one of four lenses, including three aspheric lenses (Acrysof SN60WF, Tecnis ZA9000, and Hoya Py60AD) and one spherical lens (Acrysof SN60AT). Contrast sensitivity, higher-order aberrations of the whole eye, and pupil diameter under photopic and mesopic conditions were measured 1 month postoperatively. Higher-order aberrations were decomposed into Zernike coefficients, calculated according to individual pupil diameter. The correlation between higher-order aberrations and contrast sensitivity was evaluated. RESULTS: There were no significant differences in contrast sensitivity function between the four types of lenses under photopic conditions. However, the contrast sensitivity function and area under log contrast sensitivity function in the aspheric lenses were significantly better than in the spherical lens under mesopic conditions. Under mesopic conditions, spherical aberration in eyes with aspheric lenses was significantly lower than in eyes with spherical lenses (P < 0.05). Under photopic conditions, coma aberration had a significant negative correlation with contrast sensitivity at 12 cycles/degree. Under mesopic conditions, spherical aberration had a significant negative correlation with contrast sensitivity at 3, 6, and 12 cycles/degree with glare, and with contrast sensitivity at 6 and 18 cycles/degree without glare. CONCLUSION: In terms of influence on visual function, coma aberration may be more significant under photopic conditions and spherical aberration under mesopic conditions.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA