Distribution of angle α and angle κ in a population with cataract in Shanghai

Meng, Jiaqi; Du, Yu; Wei, Ling; Yao, Yunqian; He, Wenwen; Qian, Dong−Jin; Lu, Yi; Zhu, Xiangjia

doi:10.1097/j.jcrs.0000000000000490

Cited by 26 publications

(24 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mahr et al, however, found an average of 0.42 mm for α in a large population, using a different definition for the piercing point of the optical axis, which was defined to be the center of the limbus [12]. This value for alpha is consistent with the findings from Meng et al, who also found that the angle κ is usually smaller than α with an average of 0.3 mm ± 0.18 mm compared to 0.45 mm ± 0.21 mm, respectively [13]. However, significantly different values can also be found in literature.…”

supporting

confidence: 86%

“…Later, LeGrand and El Hage stated that α is between 4°and 8°(5°on average) and that α may be larger in hyperopic eyes than in myopic eyes, which may even have negative values for α [10]. This fact is geometrically easy to understand when considering α in a right triangle spanned by the legs of the axial length and the lateral displacement of the fovea and has been demonstrated by a recent study [13]. An α of 5°a pproximately corresponds to an α distance of 0.63 mm [10].…”

mentioning

confidence: 97%

“…An α of 5°a pproximately corresponds to an α distance of 0.63 mm [10]. The magnitude for α has also been incorporated in some advanced theoretical eye models such as the Liou Brennan Model Eye [13]. Mahr et al, however, found an average of 0.42 mm for α in a large population, using a different definition for the piercing point of the optical axis, which was defined to be the center of the limbus [12].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Angle alpha as predictor for improving patient satisfaction with multifocal intraocular lenses?

Grzybowski

Eppig

2021

Graefes Arch Clin Exp Ophthalmol

View full text Add to dashboard Cite

supporting

confidence: 86%

mentioning

confidence: 97%

mentioning

confidence: 99%

See 1 more Smart Citation

Angle alpha as predictor for improving patient satisfaction with multifocal intraocular lenses?

Grzybowski

Eppig

2021

Graefes Arch Clin Exp Ophthalmol

View full text Add to dashboard Cite

“…In the high myopia group, the PC of both the right and left eyes was predominantly nasal to the CV, which was similar to a study that found that the PC gradually shifted to the nasal side of the CV as the axial length increased. 25 This may be attributed to a near shift of vision and refractive internal strabismus in high myopia. 26 Closer vision caused a convergence reflex in both eyes, resulting in a shift of the PC to the nasal side.…”

Section: Discussionmentioning

confidence: 99%

Characteristics of Pupil Offset in Young Asian Adults With Mild-Moderate and High Myopia

Sun

Liu

et al. 2022

Trans. Vis. Sci. Tech.

View full text Add to dashboard Cite

Purpose The purpose of this study was to explore the characteristics of pupil offset in young Asian adults with myopia. Methods In total, 1200 eyes (600 young adults, 18–35 years old) were divided into mild-moderate and high groups according to equivalent spherical diopters (SEQ). The pupil offset and its X and Y components were compared between the groups. Linear correlation was analyzed among pupil offset, X and Y components, and SEQ. Multiple linear regression analysis was conducted for pupil offset and eye parameters. Results The mean age of all subjects was 22.5 ± 4.8 years. The mean magnitude of the pupil offset (0.18 ± 0.09 mm vs. 0.15 ± 0.08 mm) and Y component (0.12 ± 0.08 mm vs. 0.10 ± 0.07 mm) were larger in the high group than in the mild-moderate group ( P < 0.05). The magnitude of pupil offset, X and Y components, and SEQ were positively correlated. The pupil center (PC) of the right eye in the mild-moderate group was mainly superotemporal to the corneal vertex and mainly superonasal for the left eye and both eyes in the high group. Multiple linear regression analysis revealed that the magnitude of pupil offset correlated with central corneal thickness, intraocular pressure, and mean corneal curvature ( P < 0.05). Conclusions The magnitude of the pupil offset that correlated with partial eye parameters and its X and Y components increased as the SEQ increased, and the PC gradually shifted toward the superonasal direction in young Asian adults with myopia. Translational Relevance Subjects with high myopia with a larger pupil offset should be considered for better postoperative visual quality during refractive surgery.

show abstract

“…The AR-FMI angle-k results were signi cantly correlated with the Lens-star 900 measurements with a mean of 0.41±0.22 and 0.38±0.24 mm, respectively. In the literature, there are previous studies have measured angle-k using various devices, such as Orbscan II, synoptophore, OPD-Scan III, Pentacam and Keratron Scout, which are based on different mechanisms (1)(2)(3)(4)(5). Angle-k has also been measured indirectly using…”

Section: Discussionmentioning

confidence: 99%

Measuring Angle Kappa Using the Autorefractometer

Yolcu

2022

Preprint

View full text Add to dashboard Cite

Purpose: The aim of this study was to present a novel angle kappa (k) measurement method and angle k grading scale. Methods: Two hundred sixty eyes of 130 subjects were included in the study. All eyes were evaluated using autorefractometer front monitor image (Canon, RK-F1, and U.S.A). The distance from center of the pupil to the visual axis on the autorefractometer front monitor image (AR-FMI) was measured using Image J software (http://rsbweb.nih.gov/ij). Sixty eyes of 30 subjects were evaluated using the Lens-star 900 (Haag-Streit AG, Koeniz, Switzerland) and Lens-star 900 angle k values were compared with autorefractometer measurements to analyze reliability of the method. Factors that may influence the angle-k value were analyzed. Additionally, an AR-FMI angle-k grading scale was developed and presented in the study. Results: The mean AR-FMI angle-k was 0.41±22 mm and Lens-star 900 angle-k was 0.38±24 mm, respectively. Pearson correlation test was used to analyze the test reliability and there was statistically significant positive correlation among the two methods (r: 0.628, p<0.001). The mean AR-FMI angle-k was higher at old and adult subjects when compared with young subjects, and the difference was statistically significant (p:0.02 and p:0.04, respectively). According to the AR-FMI analyzes, old subjects had narrow and nasally decentralized pupils when compared with young subjects and differences were statistically significant (p<0.00 and p<0.03, respectively). According to the AR-FMI angle kappa grading scale; 36.1% of subjects was grade 1, 38.3 % was grade 2 in x coordinate, and 58.5% was grade 1 in y coordinate. Conclusion: A novel method to evaluate the angle-k and the factors influencing the angle-k were described in the current study. According to the results, angle-k can be measured using an easily evaluable, cost-effective device which is present in every ophthalmic clinic and a grading scale may be useful to analyze the angle-k and pupillary properties.

show abstract

Distribution of angle α and angle κ in a population with cataract in Shanghai

Abstract: Angle α and angle κ, mainly located temporal to the visual axis, change nonlinearly as axial length increased, and their locations gradually shifted to the nasal side.

Cited by 26 publications

References 20 publications

Angle alpha as predictor for improving patient satisfaction with multifocal intraocular lenses?

Angle alpha as predictor for improving patient satisfaction with multifocal intraocular lenses?

Characteristics of Pupil Offset in Young Asian Adults With Mild-Moderate and High Myopia

Measuring Angle Kappa Using the Autorefractometer

Contact Info

Product

Resources

About