Search

Your search keyword '"Twelker, J Daniel"' showing total 42 results
Start Over Author "Twelker, J Daniel"
42 results on '"Twelker, J Daniel"'

12. The Contributions of Near Work and Outdoor Activity to the Correlation Between Siblings in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study

Author

Jones-Jordan, Lisa A., primary, Sinnott, Loraine T., additional, Graham, Nicholas D., additional, Cotter, Susan A., additional, Kleinstein, Robert N., additional, Manny, Ruth E., additional, Mutti, Donald O., additional, Twelker, J. Daniel, additional, and Zadnik, Karla, additional

Published
2014
Full Text
View/download PDF

13. Accommodation in Astigmatic Children During Visual Task Performance

Author

Harvey, Erin M., primary, Miller, Joseph M., additional, Apple, Howard P., additional, Parashar, Pavan, additional, Twelker, J. Daniel, additional, Crescioni, Mabel, additional, Davis, Amy L., additional, Leonard-Green, Tina K., additional, Campus, Irene, additional, and Sherrill, Duane L., additional

Published
2014
Full Text
View/download PDF

18. Corneal and Crystalline Lens Dimensions Before and After Myopia Onset

Author

Mutti, Donald O., primary, Mitchell, G. Lynn, additional, Sinnott, Loraine T., additional, Jones-Jordan, Lisa A., additional, Moeschberger, Melvin L., additional, Cotter, Susan A., additional, Kleinstein, Robert N., additional, Manny, Ruth E., additional, Twelker, J. Daniel, additional, and Zadnik, Karla, additional

Published
2012
Full Text
View/download PDF

21. Intraocular Pressure, Ethnicity, and Refractive Error

Author

Manny, Ruth E., primary, Mitchell, G. Lynn, additional, Cotter, Susan A., additional, Jones-Jordan, Lisa A., additional, Kleinstein, Robert N., additional, Mutti, Donald O., additional, Twelker, J. Daniel, additional, and Zadnik, Karla, additional

Published
2011
Full Text
View/download PDF

22. Visual Activity before and after the Onset of Juvenile Myopia

Author

Jones-Jordan, Lisa A., primary, Mitchell, G. Lynn, additional, Cotter, Susan A., additional, Kleinstein, Robert N., additional, Manny, Ruth E., additional, Mutti, Donald O., additional, Twelker, J. Daniel, additional, Sims, Janene R., additional, and Zadnik, Karla, additional

Published
2011
Full Text
View/download PDF

25. Children’s Ocular Components and Age, Gender, and Ethnicity

Author

Twelker, J Daniel, primary, Mitchell, G Lynn, additional, Messer, Dawn H., additional, Bhakta, Rita, additional, Jones, Lisa A., additional, Mutti, Donald O., additional, Cotter, Susan A., additional, Kleinstein, Robert N., additional, Manny, Ruth E., additional, and Zadnik, Karla, additional

Published
2009
Full Text
View/download PDF

28. Accommodative Lag before and after the Onset of Myopia

Author

Mutti, Donald O., primary, Mitchell, G. Lynn, additional, Hayes, John R., additional, Jones, Lisa A., additional, Moeschberger, Melvin L., additional, Cotter, Susan A., additional, Kleinstein, Robert N., additional, Manny, Ruth E., additional, Twelker, J. Daniel, additional, and Zadnik, Karla, additional

Published
2006
Full Text
View/download PDF

30. A Survey of Clinical Prescribing Philosophies for Hyperopia

Author

LYONS, STACY AYN, primary, JONES, LISA A., additional, WALLINE, JEFFREY J., additional, BARTOLONE, AMELIA G., additional, CARLSON, NANCY B., additional, KATTOUF, VALERIE, additional, HARRIS, MONICA, additional, MOORE, BRUCE, additional, MUTTI, DONALD O., additional, and TWELKER, J. DANIEL, additional

Published
2004
Full Text
View/download PDF

38. Response Properties of Normal Observers and Patients During Automated Perimetry

Author

Nelson-Quigg, Jacqueline M., Twelker, J. Daniel, and Johnson, Chris A.

Abstract

• Automated perimetry was performed on both eyes of 54 normal subjects, 36 patients with ocular hypertension and normal visual fields, and 20 patients with early glaucomatous visual field loss to evaluate false-positive errors, false-negative errors, fixation losses, consistency of double determinations, and testing time. For all subject groups and response measures, large interindividual variation was found. No meaningful age-related changes were obtained for false-negative errors, false-positive errors, fixation losses, or consistency of double determinations. Contrary to earlier reports, we found a low number of normal subjects and patients exceeding the 33% false-positive and false-negative limits established for the Humphrey Field Analyzer. A large number of normal subjects and patients, however, exceeded the 20% limits for fixation losses.

Published
1989
Full Text
View/download PDF

39. Age-related changes in the central visual field for short-wavelength-sensitive pathways

Author

Johnson, Chris A., Adams, Anthony J., Twelker, J. Daniel, and Quigg, Jacqueline M.

Abstract

The sensitivity of short-wavelength-sensitive (SWS) cone pathways throughout the central 30-deg visual field was determined in both eyes of 62 normal volunteers between the ages of 20 and 72 years. We found an average SWS cone pathway sensitivity decrease with age of ~0.15 log unit per decade. The sensitivity reduction was approximately linear, with a slightly larger decrease beyond the age of 50 years. The age-related SWS cone pathway sensitivity reductions also became larger as a function of increasing stimulus eccentricity. Measurements of ocular-media absorption characteristics in each eye revealed that 30–40% of the age-related sensitivity loss could be attributed to reductions in transmission of short-wavelength light by the ocular media. After corrections for preretinal media transmission loss, the decrease in the sensitivity of SWS cone pathways with age was ~0.09 log unit per decade. This age-related loss is greater than age-related sensitivity decreases in the middle-wavelength-sensitive and/or long-wavelength-sensitive cones (appoximately 0.06 to 0.07 log unit per decade). In the age group older than 60 years, there was an inverse relationship between media-corrected SWS cone pathway sensitivity and media absorption characteristics (i.e., media-corrected SWS cone pathway sensitivity was higher in eyes with lower media transmission of short wavelengths). This relationship was not so evident for younger subjects. A similar inverse relationship between transmission loss in the ocular media and SWS cone pathway sensitivity was found between left and right eyes of the same individual. These findings raise the possibility that reductions in short-wavelength transmission by the ocular media may have a long-term protective effect against light-induced damage to SWS cone pathways.

Published
1988

40. Myopia Progression as a Function of Sex, Age, and Ethnicity.

Author

Jones-Jordan LA, Sinnott LT, Chu RH, Cotter SA, Kleinstein RN, Manny RE, Mutti DO, Twelker JD, and Zadnik K

Subjects
Age Distribution, Child, Disease Progression, Follow-Up Studies, Humans, Myopia, Degenerative physiopathology, Prevalence, Reading, Retrospective Studies, Risk Factors, Sex Distribution, United States epidemiology, Ethnicity, Forecasting, Myopia, Degenerative ethnology, Refraction, Ocular physiology
Abstract

Purpose: To model juvenile-onset myopia progression as a function of race/ethnicity, age, sex, parental history of myopia, and time spent reading or in outdoor/sports activity., Methods: Subjects were 594 children in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study with at least three study visits: one visit with a spherical equivalent (SPHEQ) less myopic/more hyperopic than -0.75 diopter (D), the first visit with a SPHEQ of -0.75 D or more myopia (onset visit), and another after myopia onset. Myopia progression from the time of onset was modeled using cubic models as a function of age, race/ethnicity, and other covariates., Results: Younger children had faster progression of myopia; for example, the model-estimated 3-year progression in an Asian American child was -1.93 D when onset was at age 7 years compared with -1.43 D when onset was at age 10 years. Annual progression for girls was 0.093 D faster than for boys. Asian American children experienced statistically significantly faster myopia progression compared with Hispanic (estimated 3-year difference of -0.46 D), Black children (-0.88 D), and Native American children (-0.48 D), but with similar progression compared with White children (-0.19 D). Parental history of myopia, time spent reading, and time spent in outdoor/sports activity were not statistically significant factors in multivariate models., Conclusions: Younger age, female sex, and racial/ethnic group were the factors associated with faster myopic progression. This multivariate model can facilitate the planning of clinical trials for myopia control interventions by informing the prediction of myopia progression rates.

Published
2021
Full Text
View/download PDF

41. The Response AC/A Ratio Before and After the Onset of Myopia.

Author

Mutti DO, Mitchell GL, Jones-Jordan LA, Cotter SA, Kleinstein RN, Manny RE, Twelker JD, and Zadnik K

Subjects
Adolescent, Child, Disease Progression, Female, Follow-Up Studies, Humans, Male, Myopia diagnosis, Retrospective Studies, Time Factors, Accommodation, Ocular physiology, Convergence, Ocular physiology, Myopia physiopathology, Refraction, Ocular physiology
Abstract

Purpose: To investigate the ratio of accommodative convergence per diopter of accommodative response (AC/A ratio) before, during, and after myopia onset., Methods: Subjects were 698 children aged 6 to 14 years who became myopic and 430 emmetropic children participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error. Refractive error was measured using cycloplegic autorefraction, near work by parent survey, and the AC/A ratio by simultaneously monitoring convergence and accommodative response. The response AC/A ratios of children who became myopic were compared with age-, sex-, and ethnicity-matched model estimates for emmetropic children from 5 years before through 5 years after the onset of myopia., Results: The response AC/A ratio was not significantly different between the two groups 5 years before onset, then increased monotonically in children who became myopic until reaching a plateau at myopia onset of about 7 Δ/D compared to about 4 Δ/D for children who remained emmetropic (differences between groups significant at P < 0.01 from 4 years before onset through 5 years after onset). A higher AC/A ratio was associated with greater accommodative lag but not with the rate of myopia progression regardless of the level of near work., Conclusions: An increasing AC/A ratio is an early sign of becoming myopic, is related to greater accommodative lag, but does not affect the rate of myopia progression. The association with accommodative lag suggests that the AC/A ratio increase is from greater neural effort needed per diopter of accommodation rather than change in the accommodative convergence crosslink gain relationship.

Published
2017
Full Text
View/download PDF

42. Longitudinal change and stability of refractive, keratometric, and internal astigmatism in childhood.

Author

Harvey EM, Miller JM, Twelker JD, and Sherrill DL

Subjects
Adolescent, Arizona epidemiology, Astigmatism physiopathology, Child, Child, Preschool, Cross-Sectional Studies, Female, Follow-Up Studies, Humans, Male, Prevalence, Retrospective Studies, Time Factors, Astigmatism ethnology, Indians, North American, Refraction, Ocular physiology
Abstract

Purpose: To assess longitudinal change in refractive, keratometric, and internal astigmatism in a sample of students from a population with a high prevalence of with-the-rule (WTR) astigmatism and to determine the optical origins of changes in refractive astigmatism., Methods: A retrospective analysis of longitudinal measurements of right eye refractive and keratometric astigmatism in Tohono O'odham Native American children was conducted. Changes in refractive and keratometric astigmatism per year were compared in a younger cohort (n = 1594, 3 to <11 years old) and an older cohort (n = 648, 11 to <19 years old). Data were analyzed in clinical notation (Cyl) and vector notation (J0, J45)., Results: On average, refractive astigmatism (means: 1.19 diopters [D] Cyl, +0.54 J0, +0.03 J45) resulted primarily from WTR corneal astigmatism (means: +0.85 J0, -0.02 J45) and against-the-rule (ATR) internal astigmatism (means: -0.31 J0, +0.05 J45). Mean longitudinal changes in astigmatism were statistically significant (younger cohort -0.02 D/y Cyl; older cohort +0.06 D/y Cyl). In the younger cohort, astigmatism decreased with age in low and moderate astigmats (<3.00 D) and increased with age in high astigmats (≥3.00 D). In the older cohort, astigmatism increased with age across all levels of astigmatism. Longitudinal changes in keratometric and internal astigmatism were negatively correlated in both cohorts., Conclusions: Cross-sectional data suggest the presence of a constant ATR contribution from internal astigmatism (0.60 D Cyl) that is close to the 0.50 D ATR constant reported by Javal and others. Highly astigmatic 3- to <11-year-old children and children older than age 11 years show a small (not clinically significant) increase in astigmatism with age. A negative correlation between changes in keratometric astigmatism and internal astigmatism suggests an active compensation that may contribute to the stability of astigmatism in Tohono O'odham children., (Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.)

Published
2014
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results