Journal articles: 'Grand seiko autorefractor'

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DAVIES, LEON NICHOLAS, EDWARD ARTHUR HARRY MALLEN, JAMES STUART WOLFFSOHN, and and BERNARD GILMARTIN. "Clinical Evaluation of the Shin-Nippon NVision-K 5001/Grand Seiko WR-5100K Autorefractor." Optometry and Vision Science 80, no. 4 (April 2003): 320–24. http://dx.doi.org/10.1097/00006324-200304000-00011.

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WOLFFSOHN, JAMES STUART, KAZUHIKO UKAI, and BERNARD GILMARTIN. "Dynamic Measurement of Accommodation and Pupil Size Using the Portable Grand Seiko FR-5000 Autorefractor." Optometry and Vision Science 83, no. 5 (May 2006): 306–10. http://dx.doi.org/10.1097/01.opx.0000216059.54932.3a.

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Ying, Gui-shuang, Maureen G. Maguire, Marjean Taylor Kulp, Elise Ciner, Bruce Moore, Maxwell Pistilli, and Rowan Candy. "Comparison of cycloplegic refraction between Grand Seiko autorefractor and Retinomax autorefractor in the Vision in Preschoolers–Hyperopia in Preschoolers (VIP-HIP) Study." Journal of American Association for Pediatric Ophthalmology and Strabismus 21, no. 3 (June 2017): 219–23. http://dx.doi.org/10.1016/j.jaapos.2017.05.008.

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Gehring, Alyssa M., Jennifer X. Haensel, Molly K. Curtiss, and Tawna L. Roberts. "Validation of the PowerRef 3 for Measuring Accommodation: Comparison With the Grand Seiko WAM-5500A Autorefractor." Translational Vision Science & Technology 11, no. 10 (October 18, 2022): 25. http://dx.doi.org/10.1167/tvst.11.10.25.

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Chinn, Ryan N., Aparna Raghuram, Molly K. Curtiss, Alyssa M. Gehring, Ana Juric De Paula, and Tawna L. Roberts. "Repeatability of the Accommodative Response Measured by the Grand Seiko Autorefractor in Children With and Without Amblyopia and Adults." American Journal of Ophthalmology 236 (April 2022): 221–31. http://dx.doi.org/10.1016/j.ajo.2021.10.019.

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Gyldenkerne, Anders, Nicolaj Aagaard, Malene Jakobsen, Carina Toftelund, and Jesper Hjortdal. "Changes in accommodative function following small-incision lenticule extraction for high myopia." PLOS ONE 15, no. 12 (December 30, 2020): e0244602. http://dx.doi.org/10.1371/journal.pone.0244602.

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Purpose To examine whether the amplitude of accommodation, the accommodative response, and the accommodative facility is affected and correlated with changes in higher-order aberrations for patients with high myopia surgically treated with small-incision lenticule extraction (SMILE). Methods 35 highly myopic eyes (myopic spherical equivalent of at least 6 diopters) of 35 patients treated with SMILE were included. Assessments were made before and 3 months after surgery. Donders push-up-method was used to measure the amplitude of accommodation. The accommodative response was assessed using an open-field autorefractor”Grand Seiko WAM-5500” (Grand Seiko Co. Ltd., Hiroshima, Japan) in combination with a Badal optometer and stimuli of accommodation at 0.0, 0.5, 1.25, 2.0, 3.0, and 4.0 D, respectively. Accommodative facility was measured at 40 cm with ±2,00D flipper lenses. All measurements of accommodation were performed monocularly with the refractive error corrected with soft contact lenses. Results The amplitude of accommodation did not change statistically significantly (mean difference -0.24 D (SD 0.98), 95% CI of mean difference -0.58 D to 0.11 D, paired-sample t(34) = -1.39; P = 0.17). The accommodative responses at 0.0, 0.5, 1.25, 2.0, 3.0, and 4.0 D did not statistically significantly change either (F(6,29) = 1.15; P = .36). Finally, the accommodative facility was also unchanged with a mean difference of 1.11 cycles per minute (SD 5.11, 95% CI of mean difference -0.64 to 2.87, paired-sample t(34) = 1.29; P = 0.21). No clinically significant associations between changes in accommodation and higher-order aberrations were found. Conclusions SMILE does not alter the amplitude of accommodation, the accommodative response, nor the accommodative facility for highly myopic patients, and the surgically induced corneal higher-order aberrations do not affect the accommodative function.

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Kimura, Shuhei, Satoshi Hasebe, and Hiroshi Ohtsuki. "Systematic measurement errors involved in over-refraction using an autorefractor (Grand-Seiko WV-500): is measurement of accommodative lag through spectacle lenses valid?" Ophthalmic and Physiological Optics 27, no. 3 (May 2007): 281–86. http://dx.doi.org/10.1111/j.1475-1313.2007.00466.x.

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Atchison, David A. "The use of autorefractors using the image‐size principle in determining on‐axis and off‐axis refraction. Part 3: Theoretical effect of pupil misalignment on peripheral refraction for the Grand‐Seiko Autorefractor." Ophthalmic and Physiological Optics 42, no. 3 (February 18, 2022): 653–57. http://dx.doi.org/10.1111/opo.12964.

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Liang, Xintong, Shifei Wei, Shi-Ming Li, Wenzai An, Jialing Du, and Ningli Wang. "Effect of reading with a mobile phone and text on accommodation in young adults." Graefe's Archive for Clinical and Experimental Ophthalmology 259, no. 5 (January 19, 2021): 1281–88. http://dx.doi.org/10.1007/s00417-020-05054-3.

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Abstract Purpose To investigate the effects of reading with mobile phone versus text on accommodation accuracy and near work-induced transient myopia (NITM) and its subsequent decay during near reading in young adults with mild to moderate myopia. Methods The refractions of 31 young adults were measured with an open-field autorefractor (WAM-5500, Grand Seiko) for two reading tasks with a mobile phone and text at 33 cm. The mean age of the young adults was 24.35 ± 1.80 years. The baseline refractive aspects were determined clinically with full distance refractive correction in place. The initial NITM and its decay time and accommodative lag were assessed objectively immediately after binocularly viewing a mobile phone or text for 40 min. Results The mean ± standard deviation (SD) initial NITM magnitude was greater for reading with text (0.23 ± 0.26 D) than for reading with mobile phone (0.12 ± 0.17 D), but there was no significant difference between the two reading tasks (p = 0.082). The decay time (median, first quartile, and third quartile) was 60 s (16, 154) and 70 s (32, 180) in the phone task and text task groups, respectively. There was also no significant difference in the decay time between the two reading types in general (p = 0.294). The accommodative lags of text tasks and mobile phones tasks were equivalent (1.27 ± 0.52 D vs 1.31 ± 0.64 D, p = 0.792). Conclusion There were no significant differences in accommodative lags and the initial NITM and its decay time between reading with a mobile phone and text in young adults.

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Alsaqr, Ali Mazyed, Hisham AlShareef, Faisal Alhajri, Ali Abusharha, Raied Fagehi, Ahmad Alharbi, and Saud Alanazi. "Accommodative Response in Patients with Central Field Loss: A Matched Case-Control Study." Vision 5, no. 3 (July 9, 2021): 35. http://dx.doi.org/10.3390/vision5030035.

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Purpose: This study was conducted to evaluate the accommodative response in young participants with visual impairment in comparison with visually normal participants. Methods: Fifteen participants with confirmed visual impairment and 30 visually normal participants aged 12–15 years were recruited. Accommodative response was measured using autorefractor (Grand Seiko WV500) at distances of accommodative demand of 33, 25, and 20 cm. The targets were one-line-above participant threshold acuity. The participants’ accommodative responses were compared between both groups after calibration for refractive errors and the vertex distance of the glasses. Visual acuity and refractive status were also assessed. Results: The age was not significantly different between both participant groups. The visual acuity of visually impaired patients was 6/30 to 6/240, and that of visually normal participants was 6/7.5 or better. Ten of the visually impaired patients and 29 of visually normal participants were myopic. In total, 61–73% of visually impaired patients showed an accommodative lead. Five subtypes of accommodative response were observed. In general, the accommodative inaccuracy increased with increasing accommodative demand. However, the visually normal participants largely exhibited an accommodative lag. A mild-to-moderate relationship was observed between visual acuity and accommodative response (r = 0.3–0.5, p < 0.05). Conclusion: Accommodative response in young visually impaired patients can be variable and on an individual basis. Low vision specialists should anticipate accommodative response outside the normal range. Therefore, we shall consider evaluating each patient’s accommodative response before prescribing any near addition lenses. Accommodation inaccuracy is often more complex than predicted due to increased depth of focus caused by reduced visual acuity.

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Norhani, Mohidin, Yu Chen Low, Mohd-Ali Bariah, Mohamad Shahimin Mizhanim, and Arif Norlaili. "Corneal endothelial morphology of healthy myopic Malaysian children of Chinese ethnicity aged 8-9 years and its association with axial length." F1000Research 11 (September 7, 2022): 339. http://dx.doi.org/10.12688/f1000research.110560.2.

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Background: This is a cross-sectional study to further understand the effects of axial length elongation on the corneal endothelial cell’s morphology in myopic children. Abnormal changes in the morphology of corneal endothelium are indicators of corneal stress or instability which could be linked to myopia. Methods: 111 school children comprising of 37 emmetropes, 37 mild myopes and 37 moderate myopes aged 8-9 years old were recruited. Visual acuity was measured using the LogMar chart, cycloplegic refraction was determined using an open-field autorefractor (Grand Seiko WAM-5100, Hiroshima, Japan) and refined using subjective refraction. Morphology of corneal endothelial cells [endothelial cell density, coefficient of variation, hexagonality and central corneal thickness] was evaluated using a non-contact specular microscope (Topcon SP-2000P). Axial length was measured with A-scan ultrasound biometry (PacScan Plus, Sonomed Escalon, NY). The correlation between morphology of corneal endothelial cells and axial length were assessed using Pearson Correlation and Linear regression analysis. Results: There was no significant difference in corneal endothelial cells and axial length between gender (p>0.05). Significant reduction in endothelial cells density and hexagonality and increased coefficient of variation was found in eyes of higher myopic power which had longer axial when compared to emmetropes (p<0.001). Except for central corneal thickness, all corneal endothelial cells parameters correlated significantly with axial length (p<0.05). For every 1mm increase in axial length, endothelial cells density decreased by 73.27cells/mm2, hexagonality decreased by 2.32% and coefficient of variation increased by 1.75%. Conclusions: There were significant changes in morphology of cornea endothelial cells in young moderate myopic children of Chinese ethnicity at 8-9 years of age. This result provides normative data for Malaysian children of Chinese ethnicity that can be used for comparison and reference for clinical procedures, thereby facilitating decision-making with respect to interventions for myopia control, especially in prescribing contact lens for children.

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Norhani, Mohidin, Yu Chen Low, Mohd-Ali Bariah, Mohamad Shahimin Mizhanim, and Arif Norlaili. "Corneal endothelial morphology of healthy myopic Malaysian children of Chinese ethnicity aged 8-9 years and its association with axial length." F1000Research 11 (March 21, 2022): 339. http://dx.doi.org/10.12688/f1000research.110560.1.

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Background: This is a cross-sectional study to further understand the effects of axial length elongation on the corneal endothelial cell’s morphology in myopic children. Abnormal changes in the morphology of corneal endothelium are indicators of corneal stress or instability which could be linked to myopia. Methods: 111 school children comprising of 37 emmetropes, 37 mild myopes and 37 moderate myopes aged 8-9 years old were recruited. Visual acuity was measured using the LogMar chart, cycloplegic refraction was determined using an open-field autorefractor (Grand Seiko WAM-5100, Hiroshima, Japan) and refined using subjective refraction. Morphology of corneal endothelial cells [endothelial cell density, coefficient of variation, hexagonality and central corneal thickness] was evaluated using a non-contact specular microscope (Topcon SP-2000P). Axial length was measured with A-scan ultrasound biometry (PacScan Plus, Sonomed Escalon, NY). The correlation between morphology of corneal endothelial cells and axial length were assessed using Pearson Correlation and Linear regression analysis. Results: There was no significant difference in corneal endothelial cells and axial length between gender (p>0.05). Significant reduction in endothelial cells density and hexagonality and increased coefficient of variation was found in eyes of higher myopic power which had longer axial when compared to emmetropes (p<0.001). Except for central corneal thickness, all corneal endothelial cells parameters correlated significantly with axial length (p<0.05). For every 1mm increase in axial length, endothelial cells density decreased by 73.27cells/mm2, hexagonality decreased by 2.32% and coefficient of variation increased by 1.75%. Conclusions: There were significant changes in morphology of cornea endothelial cells in young moderate myopic children of Chinese ethnicity at 8-9 years of age. This result provides normative data for Malaysian children of Chinese ethnicity that can be used for comparison and reference for clinical procedures, thereby facilitating decision-making with respect to interventions for myopia control, especially in prescribing contact lens for children.

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Gopalakrishnan, Aparna, Jameel Rizwana Hussaindeen, Viswanathan Sivaraman, Meenakshi Swaminathan, Yee Ling Wong, James Andrew Armitage, Alex Gentle, and Simon Backhouse. "The Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study—Defining a Threshold for Non-Cycloplegic Myopia Prevalence in Children." Journal of Clinical Medicine 10, no. 6 (March 15, 2021): 1215. http://dx.doi.org/10.3390/jcm10061215.

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The aim of this study was to investigate the agreement between cycloplegic and non-cycloplegic autorefraction with an open-field auto refractor in a school vision screening set up, and to define a threshold for myopia that agrees with the standard cycloplegic refraction threshold. The study was conducted as part of the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) study, which investigated the prevalence, incidence, and risk factors for myopia among children in South India. Children from two schools aged 5 to 15 years, with no ocular abnormalities and whose parents gave informed consent for cycloplegic refraction were included in the study. All the children underwent visual acuity assessment (Pocket Vision Screener, Elite school of Optometry, India), followed by non-cycloplegic and cycloplegic (1% tropicamide) open-field autorefraction (Grand Seiko, WAM-5500). A total of 387 children were included in the study, of whom 201 were boys. The mean (SD) age of the children was 12.2 (±2.1) years. Overall, the mean difference between cycloplegic and non-cycloplegic spherical equivalent (SE) open-field autorefraction measures was 0.34 D (limits of agreement (LOA), 1.06 D to −0.38 D). For myopes, the mean difference between cycloplegic and non-cycloplegic SE was 0.13 D (LOA, 0.63D to −0.36D). The prevalence of myopia was 12% (95% CI, 8% to 15%) using the threshold of cycloplegic SE ≤ −0.50 D, and was 14% (95% CI, 11% to 17%) with SE ≤ −0.50 D using non-cycloplegic refraction. When myopia was defined as SE of ≤−0.75 D under non-cycloplegic conditions, there was no difference between cycloplegic and non-cycloplegic open-field autorefraction prevalence estimates (12%; 95% CI, 8% to 15%; p = 1.00). Overall, non-cycloplegic refraction underestimates hyperopia and overestimates myopia; but for subjects with myopia, this difference is minimal and not clinically significant. A threshold of SE ≤ −0.75 D agrees well for the estimation of myopia prevalence among children when using non-cycloplegic refraction and is comparable with the standard definition of cycloplegic myopic refraction of SE ≤ −0.50 D.

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Atchison, David A., Marwan Suheimat, Stanislovas Zacharovas, and Charles E. Campbell. "The use of autorefractors using the image‐size principle in determining on‐axis and off‐axis refraction. Part 2: Theoretical study of peripheral refraction with the Grand Seiko AutoRef/Keratometer WAM‐5500." Ophthalmic and Physiological Optics 42, no. 2 (December 20, 2021): 293–300. http://dx.doi.org/10.1111/opo.12936.

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Zhang, Liyue, Dongyu Guo, Chen Xie, Yingying Wen, Xuhong Zhang, Le Jin, Jianping Tong, and Ye Shen. "The effects of colour and temporal frequency of flickering light on variability of the accommodation response in emmetropes and myopes." BMC Ophthalmology 21, no. 1 (February 17, 2021). http://dx.doi.org/10.1186/s12886-021-01856-z.

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Abstract Background Myopia is hypothesized to be influenced by environmental light conditions. For example, it has been shown that colour and temporal frequency of flickering light affect emmetropisation in animals. Considering the omnipresence of flickering light in our daily life, we decided to analyze the effect of colour flickers on variability of the accommodation response (VAR) in emmetropes and myopes. Methods We measured the dynamic accommodative responses of 19 emmetropic and 22 myopic adults using a Grand Seiko WAM-5500 open-field autorefractor. The subjects focused for more than 20 s on a black Snellen E target against three different backgrounds made up of three colour flicker combinations (red/green, red/blue and blue/green) and under five frequency conditions (0.20 Hz, 0.50 Hz, 1.00 Hz, 1.67 Hz, and 5.00 Hz). Results Flicker frequency and colour both had a significant effect on VAR. Lower frequencies were associated with larger variability. Colour had an effect only at low frequencies, and red/blue colour flicker resulted in the largest variability. The variability in myopes were larger than those in emmetropes. Conclusions These findings support the hypothesis that further studies on the colour and temporal frequency of flickering light can lead to a better understanding of the development and progression of myopia.

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Queirós, António, Alejandro Cerviño, and José Manuel González-Méijome. "Peripheral refraction of myopic eyes with spectacle lenses correction and lens free emmetropes during accommodation." Eye and Vision 8, no. 1 (December 2021). http://dx.doi.org/10.1186/s40662-021-00267-x.

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Abstract Purpose To measure axial and off-axis refraction patterns in myopic eyes with spectacle lenses correction and lens free emmetropes in young healthy subjects at different target distances from 2.00 m (0.50 D) to 0.20 m (5.00 D) in terms of sphere, astigmatism, and spherical equivalent refraction. Methods Refraction was measured at the center, 20 and 40 degrees from the line of sight both nasally and temporally in 15 emmetropic and 25 myopic young healthy subjects with an open field, binocular, infrared autorefractor (Grand Seiko WAM-5500, Hiroshima, Japan). Fixation target was a Maltese cross set at 2.00, 0.50, 0.33 and 0.20 m from the corneal plane. Changes in off-axis refraction with accommodation level were normalized with respect to distance axial values and compared between myopic eyes with spectacle lenses correction and lens free emmetropes. Results Off-axis refraction in myopic eyes with spectacle lenses correction was significantly more myopic in the temporal retina compared to lens free emmetropes except for the closest target distance. Relative off-axis refractive error changed significantly with accommodation when compared to axial refraction particularly in the myopic group. This change in the negative direction was due to changes in the spherical component of refraction that became more myopic relative to the center at the 0.20 m distance as the J0 component of astigmatism was significantly reduced in both emmetropes and myopes for the closest target. Conclusion Accommodation to very near targets (up to 0.20 m) makes the off-axis refraction of myopes wearing their spectacle correction similar to that of lens free emmetropes. A significant reduction in off-axis astigmatism was also observed for the 0.20 m distance.

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Qi, Ziyi, Linlin Du, Jun Chen, Xun Xu, Xiangui He, and Jun Qiang. "Accommodative responses under various viewing conditions in surgical patients with intermittent exotropia: an institutional, retrospective study." BMC Ophthalmology 22, no. 1 (May 4, 2022). http://dx.doi.org/10.1186/s12886-022-02434-7.

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Abstract Purpose To investigate the difference of spherical equivalent (SE) and pupil diameter in adult patients with intermittent exotropia (IXT) under various viewing conditions before and after surgery. Methods We retrospectively analyzed the medical records of 23 adult patients who underwent a surgery for IXT. The angle of deviation was measured by the prism and alternative cover test. Refractive error and pupil diameter were measured using the Grand Seiko WAM-5500 open-field autorefractor under binocular and monocular viewing conditions when patients stared at distance (6 m) and near (33 cm). Regression analyses were performed between accommodative load and the angle of deviation. Results Twenty-three patients (10 males, 13 females) with a mean age of 31.17±8.95 years, of whom 13 (56.5%) had the right eye as the dominant eye. The mean angle of deviation at near and at distance was 69.57±26.37 and 65.43±28.92 prism diopters respectively. There were no significant differences in accommodative response and pupil diameter between the dominant and non-dominant eyes. SE decreased when patients changed from monocular to binocular viewing, and from distant to near viewing (all P< 0.05), so as the pupil diameter (all P< 0.001). During binocular, not monocular viewing, SE was significantly greater after operation than it was before operation (P< 0.001). Accommodative load and pupillary constriction narrowed (p< 0.001) after the operation. Linear regression analysis showed a correlation between the angle of deviation at distance and accommodative load at distance (r2=0.278, p=0.010) and at near (r2=0.332, p=0.005). Conclusion In order to maintain ocular alignment, patients with IXT suffer a large accommodative load, which is related to the angle of deviation. Surgery helps eliminating extra accommodation.

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Journal articles on the topic 'Grand seiko autorefractor'

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