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Tetsuro Oshika - One of the best experts on this subject based on the ideXlab platform.
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Improvement in Contrast Sensitivity Function after Lacrimal Passage Intubation in Eyes with Epiphora.
Journal of clinical medicine, 2020Co-Authors: Sujin Hoshi, Takahiro Hiraoka, Kuniharu Tasaki, Tetsuro OshikaAbstract:This prospective case series aimed to investigate the Contrast Sensitivity Function before and after lacrimal passage intubation (LPI) in eyes with epiphora due to lacrimal passage obstruction. We included 58 eyes of 51 patients who underwent LPI for lacrimal passage obstruction. The best-corrected visual acuity (BCVA), Contrast Sensitivity Function, and lower tear meniscus were compared before LPI and one month after lacrimal duct stent removal. The area under the log Contrast Sensitivity Function (AULCSF) was calculated for the analyses. Lower tear meniscus was assessed using anterior segment optical coherence tomography. The BCVA was comparable (p = 0.61) before and after LPI, while AULCSF increased significantly after treatment (before LPI: 1.29 ± 0.17, after LPI: 1.37 ± 0.14, p < 0.0001). Treatment resulted in a significant increase in Contrast Sensitivity at all spatial frequencies, 3–18 cycles/degree (p < 0.01 for 3, p < 0.01 for 6, p < 0.0005 for 12, p < 0.05 for 18 cycles/degree). The lower tear meniscus parameters improved significantly after treatment (p < 0.005); however, no correlation between the changes in the tear meniscus and those of the AULCSF was found. The Contrast Sensitivity significantly improved after LPI in eyes with epiphora due to lacrimal passage obstruction.
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influence of induced decentered orthokeratology lens on ocular higher order wavefront aberrations and Contrast Sensitivity Function
Journal of Cataract and Refractive Surgery, 2009Co-Authors: Takahiro Hiraoka, C Okamoto, Fumiki Okamoto, Toshifumi Mihashi, Yoko Hirohara, Tetsuro OshikaAbstract:Purpose To quantitatively evaluate the effect of overnight orthokeratology lenses intentionally left decentered after 3 months of wear and assess the influence on clinical outcomes such as ocular higher-order wavefront aberrations and Contrast Sensitivity Function. Setting Department of Ophthalmology, Tsukuba University Hospital, Ibaraki, Japan. Methods This prospective study assessed refraction, visual acuity, corneal topography, wavefront aberration, and Contrast Sensitivity Function before and 3 months after overnight orthokeratology treatment. Decentration of the treatment zone from the center of the entrance pupil was determined using computerized videokeratography (TMS-4) and data-analysis software (MatLab). The relationship between decentration and the clinical parameters was analyzed. Results The mean age of the 23 patients (46 eyes) was 24.2 years±3.3 (SD) and the mean spherical equivalent refraction before treatment, −2.38±0.98 diopters. The mean magnitude of decentration (0.85±0.51 mm) was statistically significantly correlated with the amount of myopic correction (P Conclusion Decentered treatment of orthokeratology resulted in decreased Contrast Sensitivity after treatment, showing that centration of the procedure is crucial to good outcomes.
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Time course of changes in Contrast Sensitivity Function after application of antiglaucomatous eyedrops
Nippon Ganka Gakkai zasshi, 2009Co-Authors: Takahiro Hiraoka, Masakazu Daito, Takahiro Kiuchi, Fumiki Okamoto, Tetsuro OshikaAbstract:PURPOSE Some antiglaucomatous eyedrops can cause blurred vision after application. Contrast Sensitivity after application, however, has not been examined. The purpose of this study was to investigate the influence of antiglaucomatous eyedrops on Contrast Sensitivity Function. METHODS In 23 eyes of 23 normal volunteers (34.9 +/- 14.5 years [mean +/- SD]), Contrast Sensitivity was measured before and 2, 5, 10, and 15 minutes after application of antiglaucomatous eyedrops. Three drugs, timolol maleate ion-activated gel, timolol maleate thermosetting gel, and brinzolamide were tested in this study, and the time course of changes in Contrast Sensitivity after instillation was statistically analyzed and compared between the drugs. RESULTS All drugs significantly reduced Contrast Sensitivity Function (p
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Changes in Contrast Sensitivity Function and ocular higher order aberration by conventional myopic photorefractive keratectomy.
Japanese journal of ophthalmology, 2007Co-Authors: N. Sakata, Kazunori Miyata, Tadatoshi Tokunaga, Tetsuro OshikaAbstract:Purpose To evaluate the relation between induced changes in ocular higher order aberrations and changes in the Contrast Sensitivity Function in patients undergoing excimer laser photorefractive keratectomy (PRK).
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Contrast Sensitivity Function and ocular higher order aberrations following overnight orthokeratology
Investigative Ophthalmology & Visual Science, 2007Co-Authors: Takahiro Hiraoka, C Okamoto, Yuko Ishii, Tetsuhiko Kakita, Tetsuro OshikaAbstract:PURPOSE. To evaluate relationships among Contrast Sensitivity Function, ocular higher-order aberration, and myopic correction in eyes undergoing overnight orthokeratology for myopia. METHODS. A prospective study was conducted in 46 eyes of 23 patients undergoing orthokeratology. Inclusion criteria were spherical equivalent refraction between - 1.00 and - 4.00 diopters (D), refractive astigmatism up to 1.00 D, and best-corrected visual acuity of 20/20 or better. Ocular higher-order aberrations and Contrast Sensitivity Function were determined before and 3 months after initiation of the procedure. We measured three indices of Contrast Sensitivity Function: Contrast Sensitivity, low-Contrast visual acuity, and letter Contrast Sensitivity with the CSV-1000 charts (Vector Vision Co., Greenville, OH). Area under the log Contrast Sensitivity Function (AULCSF) was calculated from the Contrast Sensitivity data. RESULTS. Orthokeratology significantly improved logMAR uncorrected visual acuity (P < 0.0001; paired t-test) but significantly increased ocular higher-order aberrations (P < 0.0001) and decreased Contrast Sensitivity Function, including AULCSF (P < 0.0001), low-Contrast visual acuity (P = 0.0025), and letter Contrast Sensitivity (P < 0.0001; Wilcoxon signed-rank test). The induced changes in AULCSF, low-Contrast visual acuity, and letter Contrast Sensitivity by orthokeratology showed significant correlation with changes in third-order (Pearson r = -0.430, P = 0.0026; r = 0.423, P = 0.0031; and Spearman r s = -0.351, P = 0.0186, respectively), fourth-order (r = -0.418, P = 0.0035; r = 0.425, P = 0.0029; and r s = - 0.566, P = 0.0001, respectively), and total higher-order (r = -0.460, P = 0.0011; r = 0.471, P = 0.0008; and r s = -0.434, P = 0.0036, respectively) aberrations. The induced changes in Contrast Sensitivity Function and higher-order aberrations significantly correlated with the amount of myopic correction (P < 0.01). CONCLUSIONS. Orthokeratology significantly increases ocular higher-order aberrations and compromises Contrast Sensitivity Function, depending on the amount of myopic correction.
Yifeng Zhou - One of the best experts on this subject based on the ideXlab platform.
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bayesian inference of two dimensional Contrast Sensitivity Function from data obtained with classical one dimensional algorithms is efficient
Frontiers in Neuroscience, 2017Co-Authors: Xiaoxiao Wang, Huan Wang, Jinfeng Huang, Yifeng Zhou, Tzvetomir TzvetanovAbstract:The Contrast Sensitivity Function that spans the two dimensions of Contrast and spatial frequency is crucial in predicting Functional vision both in research and clinical applications. In this study, the use of Bayesian inference was proposed to determine the parameters of the two-dimensional Contrast Sensitivity Function. Two-dimensional Bayesian inference was extensively simulated in comparison to classical one-dimensional measures. Its performance on two-dimensional data gathered with different sampling algorithms was also investigated. The results showed that the two-dimensional Bayesian inference method significantly improved the accuracy and precision of the Contrast Sensitivity Function, as compared to the more common one-dimensional estimates. In addition, applying two-dimensional Bayesian estimation to the final data set showed similar levels of reliability and efficiency across widely disparate and established sampling methods (from classical one-dimensional sampling, such as Ψ or staircase, to more novel multi-dimensional sampling methods, such as quick Contrast Sensitivity Function and Fisher information gain). Furthermore, the improvements observed following the application of Bayesian inference were maintained even when the prior poorly matched the subject's Contrast Sensitivity Function. Simulation results were confirmed in a psychophysical experiment. The results indicated that two-dimensional Bayesian inference of Contrast Sensitivity Function data provides similar estimates across a wide range of sampling methods. The present study likely has implications for the measurement of Contrast Sensitivity Function in various settings (including research and clinical settings) and would facilitate the comparison of existing data from previous studies.
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noise provides new insights on Contrast Sensitivity Function
PLOS ONE, 2014Co-Authors: Ge Chen, Yifeng Zhou, Fang Hou, Fangfang Yan, Pan Zhang, Changbing HuangAbstract:Sensitivity to luminance difference, or Contrast Sensitivity, is critical for animals to survive in and interact with the external world. The Contrast Sensitivity Function (CSF), which measures visual Sensitivity to spatial patterns over a wide range of spatial frequencies, provides a comprehensive characterization of the visual system. Despite its popularity and significance in both basic research and clinical practice, it hasn't been clear what determines the CSF and how the factors underlying the CSF change in different conditions. In the current study, we applied the external noise method and perceptual template model to a wide range of external noise and spatial frequency (SF) conditions, and evaluated how the various sources of observer inefficiency changed with SF and determined the limiting factors underlying the CSF. We found that only internal additive noise and template gain changed significantly with SF, while the transducer non-linearity and coefficient for multiplicative noise were constant. The 12-parameter model provided a very good account of all the data in the 200 tested conditions (86.5%, 86.2%, 89.5%, and 96.4% for the four subjects, respectively). Our results suggest a re-consideration of the popular spatial vision model that employs the CSF as the front-end filter and constant internal additive noise across spatial frequencies. The study will also be of interest to scientists and clinicians engaged in characterizing spatial vision deficits and/or developing rehabilitation methods to restore spatial vision in clinical populations.
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Contrast Sensitivity Function after correcting residual wavefront aberrations during RGP lens wear.
Optometry and vision science : official publication of the American Academy of Optometry, 2014Co-Authors: Bi Yang, Bo Liang, Longqian Liu, Meng Liao, Yun Dai, Haoxin Zhao, Yudong Zhang, Yifeng ZhouAbstract:Purpose To investigate the effect on the Contrast Sensitivity Function (CSF) of correcting the residual wavefront aberrations in myopic and keratoconic subjects wearing rigid gas permeable (RGP) contact lenses.
C Okamoto - One of the best experts on this subject based on the ideXlab platform.
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influence of induced decentered orthokeratology lens on ocular higher order wavefront aberrations and Contrast Sensitivity Function
Journal of Cataract and Refractive Surgery, 2009Co-Authors: Takahiro Hiraoka, C Okamoto, Fumiki Okamoto, Toshifumi Mihashi, Yoko Hirohara, Tetsuro OshikaAbstract:Purpose To quantitatively evaluate the effect of overnight orthokeratology lenses intentionally left decentered after 3 months of wear and assess the influence on clinical outcomes such as ocular higher-order wavefront aberrations and Contrast Sensitivity Function. Setting Department of Ophthalmology, Tsukuba University Hospital, Ibaraki, Japan. Methods This prospective study assessed refraction, visual acuity, corneal topography, wavefront aberration, and Contrast Sensitivity Function before and 3 months after overnight orthokeratology treatment. Decentration of the treatment zone from the center of the entrance pupil was determined using computerized videokeratography (TMS-4) and data-analysis software (MatLab). The relationship between decentration and the clinical parameters was analyzed. Results The mean age of the 23 patients (46 eyes) was 24.2 years±3.3 (SD) and the mean spherical equivalent refraction before treatment, −2.38±0.98 diopters. The mean magnitude of decentration (0.85±0.51 mm) was statistically significantly correlated with the amount of myopic correction (P Conclusion Decentered treatment of orthokeratology resulted in decreased Contrast Sensitivity after treatment, showing that centration of the procedure is crucial to good outcomes.
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Contrast Sensitivity Function and ocular higher order aberrations following overnight orthokeratology
Investigative Ophthalmology & Visual Science, 2007Co-Authors: Takahiro Hiraoka, C Okamoto, Yuko Ishii, Tetsuhiko Kakita, Tetsuro OshikaAbstract:PURPOSE. To evaluate relationships among Contrast Sensitivity Function, ocular higher-order aberration, and myopic correction in eyes undergoing overnight orthokeratology for myopia. METHODS. A prospective study was conducted in 46 eyes of 23 patients undergoing orthokeratology. Inclusion criteria were spherical equivalent refraction between - 1.00 and - 4.00 diopters (D), refractive astigmatism up to 1.00 D, and best-corrected visual acuity of 20/20 or better. Ocular higher-order aberrations and Contrast Sensitivity Function were determined before and 3 months after initiation of the procedure. We measured three indices of Contrast Sensitivity Function: Contrast Sensitivity, low-Contrast visual acuity, and letter Contrast Sensitivity with the CSV-1000 charts (Vector Vision Co., Greenville, OH). Area under the log Contrast Sensitivity Function (AULCSF) was calculated from the Contrast Sensitivity data. RESULTS. Orthokeratology significantly improved logMAR uncorrected visual acuity (P < 0.0001; paired t-test) but significantly increased ocular higher-order aberrations (P < 0.0001) and decreased Contrast Sensitivity Function, including AULCSF (P < 0.0001), low-Contrast visual acuity (P = 0.0025), and letter Contrast Sensitivity (P < 0.0001; Wilcoxon signed-rank test). The induced changes in AULCSF, low-Contrast visual acuity, and letter Contrast Sensitivity by orthokeratology showed significant correlation with changes in third-order (Pearson r = -0.430, P = 0.0026; r = 0.423, P = 0.0031; and Spearman r s = -0.351, P = 0.0186, respectively), fourth-order (r = -0.418, P = 0.0035; r = 0.425, P = 0.0029; and r s = - 0.566, P = 0.0001, respectively), and total higher-order (r = -0.460, P = 0.0011; r = 0.471, P = 0.0008; and r s = -0.434, P = 0.0036, respectively) aberrations. The induced changes in Contrast Sensitivity Function and higher-order aberrations significantly correlated with the amount of myopic correction (P < 0.01). CONCLUSIONS. Orthokeratology significantly increases ocular higher-order aberrations and compromises Contrast Sensitivity Function, depending on the amount of myopic correction.
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Contrast Sensitivity Function and ocular higher order wavefront aberrations in normal human eyes
Ophthalmology, 2006Co-Authors: Tetsuro Oshika, C Okamoto, Tomokazu Samejima, Tadatoshi Tokunaga, Kazunori MiyataAbstract:Purpose To investigate the relation between Contrast Sensitivity Function and ocular higher-order wavefront aberrations in normal human eyes. Study Design Prospective observational case series. Participants Three hundred seven eyes of 161 normal subjects, ranging in age from 15 to 60 years (30.9±8.0 [mean ± standard deviation]). Methods Ocular higher-order aberrations were measured for a 4-mm pupil using the Hartmann–Shack wavefront analyzer. The root-mean-square of the third- and fourth-order Zernike coefficients was used to represent comalike and spherical-like aberrations, respectively. We measured Contrast Sensitivity, low-Contrast visual acuity (VA), and letter Contrast Sensitivity. From the Contrast Sensitivity data, the area under the log Contrast Sensitivity Function (AULCSF) was calculated. Pupil diameter in a photopic condition was recorded using a digital camera. Results Multiple linear regression analysis revealed that comalike aberration ( P = 0.002) was significantly associated with AULCSF, but spherical-like aberration ( P = 0.200), age ( P = 0.185), and photopic pupil diameter ( P =0.252) were not. Comalike aberration showed a significant correlation with low-Contrast VA ( P P = 0.293), age ( P = 0.266), and pupil diameter ( P = 0.756) did not. Comalike aberration was found to be significantly associated with letter Contrast Sensitivity ( P P =0.082), age ( P = 0.370), and pupil diameter ( P = 0.160) were not. Conclusions In normal human eyes, comalike aberration of the eye significantly influences Contrast Sensitivity Function.
Madalena Lira - One of the best experts on this subject based on the ideXlab platform.
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Contrast Sensitivity Function with soft contact lens wear
Journal of Optometry, 2020Co-Authors: Kishor Sapkota, Sandra Franco, Madalena LiraAbstract:Abstract Purposes To compare Contrast Sensitivity Function (CSF) with soft contact lens (SCL) and spectacles wear. To investigate the effect of a three-month period of SCL wear on CSF. Methods Forty-seven myopic subjects with no history of contact lens (CL) wear were included in this longitudinal prospective study. CSF was measured with spectacles using the CSV-1000 (VectorVision, Greenvile, OH). Subsequently, subjects were fitted with a daily disposable lens (Nelfilcon-A, Stenofilcon-A or Nesofilcon-A) in one eye and a monthly disposable lens (Lotrafilcon-B, Comfilcon-A or Balafilcon-A) in the other eye and wore the same type of CLs for three months. CSF was measured again on the same day and after three months wearing CLs. Differences in CSF with spectacles and CLs on baseline and changes to CSF after three months of CLs wear were assessed. The effect of lens materials and wearing modality on CSF change was also investigated. Results CSF was higher with CLs in comparison to the values with spectacles for spatial frequencies of 3, 6 and 12 cycles per degree (cpd) (p 0.05). There was no difference in CSF between hydrogel and silicone CLs as well as when comparing daily with monthly wear CLs (p > 0.05). Conclusion CSF is better with CLs than with spectacles. CSF values with CL are similar between baseline and after 3 months of lens wear.
Takahiro Hiraoka - One of the best experts on this subject based on the ideXlab platform.
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Improvement in Contrast Sensitivity Function after Lacrimal Passage Intubation in Eyes with Epiphora.
Journal of clinical medicine, 2020Co-Authors: Sujin Hoshi, Takahiro Hiraoka, Kuniharu Tasaki, Tetsuro OshikaAbstract:This prospective case series aimed to investigate the Contrast Sensitivity Function before and after lacrimal passage intubation (LPI) in eyes with epiphora due to lacrimal passage obstruction. We included 58 eyes of 51 patients who underwent LPI for lacrimal passage obstruction. The best-corrected visual acuity (BCVA), Contrast Sensitivity Function, and lower tear meniscus were compared before LPI and one month after lacrimal duct stent removal. The area under the log Contrast Sensitivity Function (AULCSF) was calculated for the analyses. Lower tear meniscus was assessed using anterior segment optical coherence tomography. The BCVA was comparable (p = 0.61) before and after LPI, while AULCSF increased significantly after treatment (before LPI: 1.29 ± 0.17, after LPI: 1.37 ± 0.14, p < 0.0001). Treatment resulted in a significant increase in Contrast Sensitivity at all spatial frequencies, 3–18 cycles/degree (p < 0.01 for 3, p < 0.01 for 6, p < 0.0005 for 12, p < 0.05 for 18 cycles/degree). The lower tear meniscus parameters improved significantly after treatment (p < 0.005); however, no correlation between the changes in the tear meniscus and those of the AULCSF was found. The Contrast Sensitivity significantly improved after LPI in eyes with epiphora due to lacrimal passage obstruction.
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influence of induced decentered orthokeratology lens on ocular higher order wavefront aberrations and Contrast Sensitivity Function
Journal of Cataract and Refractive Surgery, 2009Co-Authors: Takahiro Hiraoka, C Okamoto, Fumiki Okamoto, Toshifumi Mihashi, Yoko Hirohara, Tetsuro OshikaAbstract:Purpose To quantitatively evaluate the effect of overnight orthokeratology lenses intentionally left decentered after 3 months of wear and assess the influence on clinical outcomes such as ocular higher-order wavefront aberrations and Contrast Sensitivity Function. Setting Department of Ophthalmology, Tsukuba University Hospital, Ibaraki, Japan. Methods This prospective study assessed refraction, visual acuity, corneal topography, wavefront aberration, and Contrast Sensitivity Function before and 3 months after overnight orthokeratology treatment. Decentration of the treatment zone from the center of the entrance pupil was determined using computerized videokeratography (TMS-4) and data-analysis software (MatLab). The relationship between decentration and the clinical parameters was analyzed. Results The mean age of the 23 patients (46 eyes) was 24.2 years±3.3 (SD) and the mean spherical equivalent refraction before treatment, −2.38±0.98 diopters. The mean magnitude of decentration (0.85±0.51 mm) was statistically significantly correlated with the amount of myopic correction (P Conclusion Decentered treatment of orthokeratology resulted in decreased Contrast Sensitivity after treatment, showing that centration of the procedure is crucial to good outcomes.
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Time course of changes in Contrast Sensitivity Function after application of antiglaucomatous eyedrops
Nippon Ganka Gakkai zasshi, 2009Co-Authors: Takahiro Hiraoka, Masakazu Daito, Takahiro Kiuchi, Fumiki Okamoto, Tetsuro OshikaAbstract:PURPOSE Some antiglaucomatous eyedrops can cause blurred vision after application. Contrast Sensitivity after application, however, has not been examined. The purpose of this study was to investigate the influence of antiglaucomatous eyedrops on Contrast Sensitivity Function. METHODS In 23 eyes of 23 normal volunteers (34.9 +/- 14.5 years [mean +/- SD]), Contrast Sensitivity was measured before and 2, 5, 10, and 15 minutes after application of antiglaucomatous eyedrops. Three drugs, timolol maleate ion-activated gel, timolol maleate thermosetting gel, and brinzolamide were tested in this study, and the time course of changes in Contrast Sensitivity after instillation was statistically analyzed and compared between the drugs. RESULTS All drugs significantly reduced Contrast Sensitivity Function (p
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Contrast Sensitivity Function and ocular higher order aberrations following overnight orthokeratology
Investigative Ophthalmology & Visual Science, 2007Co-Authors: Takahiro Hiraoka, C Okamoto, Yuko Ishii, Tetsuhiko Kakita, Tetsuro OshikaAbstract:PURPOSE. To evaluate relationships among Contrast Sensitivity Function, ocular higher-order aberration, and myopic correction in eyes undergoing overnight orthokeratology for myopia. METHODS. A prospective study was conducted in 46 eyes of 23 patients undergoing orthokeratology. Inclusion criteria were spherical equivalent refraction between - 1.00 and - 4.00 diopters (D), refractive astigmatism up to 1.00 D, and best-corrected visual acuity of 20/20 or better. Ocular higher-order aberrations and Contrast Sensitivity Function were determined before and 3 months after initiation of the procedure. We measured three indices of Contrast Sensitivity Function: Contrast Sensitivity, low-Contrast visual acuity, and letter Contrast Sensitivity with the CSV-1000 charts (Vector Vision Co., Greenville, OH). Area under the log Contrast Sensitivity Function (AULCSF) was calculated from the Contrast Sensitivity data. RESULTS. Orthokeratology significantly improved logMAR uncorrected visual acuity (P < 0.0001; paired t-test) but significantly increased ocular higher-order aberrations (P < 0.0001) and decreased Contrast Sensitivity Function, including AULCSF (P < 0.0001), low-Contrast visual acuity (P = 0.0025), and letter Contrast Sensitivity (P < 0.0001; Wilcoxon signed-rank test). The induced changes in AULCSF, low-Contrast visual acuity, and letter Contrast Sensitivity by orthokeratology showed significant correlation with changes in third-order (Pearson r = -0.430, P = 0.0026; r = 0.423, P = 0.0031; and Spearman r s = -0.351, P = 0.0186, respectively), fourth-order (r = -0.418, P = 0.0035; r = 0.425, P = 0.0029; and r s = - 0.566, P = 0.0001, respectively), and total higher-order (r = -0.460, P = 0.0011; r = 0.471, P = 0.0008; and r s = -0.434, P = 0.0036, respectively) aberrations. The induced changes in Contrast Sensitivity Function and higher-order aberrations significantly correlated with the amount of myopic correction (P < 0.01). CONCLUSIONS. Orthokeratology significantly increases ocular higher-order aberrations and compromises Contrast Sensitivity Function, depending on the amount of myopic correction.