1
|
Titheradge P, Robergs R. Evaluating Airflow Sensor Methods: Precision in Indirect Calorimetry. Scand J Med Sci Sports 2024; 34:e14674. [PMID: 38895762 DOI: 10.1111/sms.14674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/21/2024]
Abstract
This study assesses the impact of three volumetric gas flow measurement methods-turbine (fT); pneumotachograph (fP), and Venturi (fV)-on predictive accuracy and precision of expired gas analysis indirect calorimetry (EGAIC) across varying exercise intensities. Six males (Age: 38 ± 8 year; Height: 178.8 ± 4.2 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ : 42 ± 2.8 mL O2 kg-1 min-1) and 14 females (Age = 44.6 ± 9.6 year; Height = 164.6 ± 6.9 cm;V ̇ O 2 peak $$ \dot{V}{\mathrm{O}}_2\mathrm{peak} $$ = 45 ± 8.6 mL O2 kg-1 min-1) were recruited. Participants completed physical exertion on a stationary cycle ergometer for simultaneous pulmonary minute ventilation (V ̇ $$ \dot{V} $$ ) measurements and EGAIC computations. Exercise protocols and subsequent conditions involved a 5-min cycling warm-up at 25 W min-1, incremental exercise to exhaustion (V ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ ramp test), then a steady-state exercise bout induced by a constant Watt load equivalent to 80% ventilatory threshold (80% VT). A linear mixed model revealed that exercise intensity significantly affectedV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ measurements (p < 0.0001), whereas airflow sensor method (p = 0.97) and its interaction with exercise intensity (p = 0.91) did not. Group analysis of precision yielded aV ̇ O 2 $$ \dot{V}{\mathrm{O}}_2 $$ CV % = 21%; SEM = 5 mL O2 kg-1 min-1. Intra- and interindividual analysis of precision via Bland-Altman revealed a 95% confidence interval (CI) precision benchmark of 3-5 mL kg-1 min-1. Agreement among methods decreased at power outputs elicitingV ̇ $$ \dot{V} $$ up to 150 L min-1, indicating a decrease in precision and highlighting potential challenges in interpreting biological variability, training response heterogeneity, and test-retest comparisons. These findings suggest careful consideration of airflow sensor method variance across metabolic cart configurations.
Collapse
Affiliation(s)
- Praneel Titheradge
- School of Allied Health, Exercise & Sports Sciences, Charles Sturt University, Port Macquarie, New South Wales, Australia
| | - Robert Robergs
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| |
Collapse
|
2
|
Bullimore MA, Brennan NA. The underestimated role of myopia in uncorrectable visual impairment in the United States. Sci Rep 2023; 13:15283. [PMID: 37714860 PMCID: PMC10504322 DOI: 10.1038/s41598-023-42108-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 09/05/2023] [Indexed: 09/17/2023] Open
Abstract
We estimate the US prevalence of uncorrectable visual impairment in 2050 accounting for the changing distribution of both age and myopia. Age projections of the US population (from an estimated total of 379 million in 2050), were taken from the US census website. The distribution of myopia, by severity, was calculated from literature-derived prevalence estimates of 58.4% (≤ - 0.50 D, 2050 projection) and 33.1% (≤ - 1.00 D, 1999-2004 estimate) to provide predicted and conservative estimates, respectively. Uncorrectable visual impairment as a function of age and refractive error was modelled by multiple linear regression. Finally, the likely number of individuals in the US with visual impairment in 2050 was calculated. For a projected myopia prevalence of 58.4%, 222 million are projected to be myopic and 48 million will have high myopia (- 5 D or worse). The projected total number with uncorrectable visual impairment is 11.4 million of which 4.9 million cases (43%) of visual impairment will be directly attributed to increased risk of eye disease associated with myopia. For a projected myopia prevalence of 33.1%, 8.9 million are projected to have uncorrectable visual impairment of which 2.4 million cases (27%) will be directly attributed to myopia. It is predicted that between 27 and 43% of uncorrectable visual impairment in the US population in 2050 will be directly attributable to myopia. Failure to account for the increasing prevalence of myopia among the aging population leads to a substantial underestimate of the prevalence of visual impairment.
Collapse
|
3
|
Kalikivayi V, Kalikivayi L, Ganesan AR. Analyses on the distribution and influence of higher-order aberrations both clinically and experimentally among varied refractive errors. Saudi J Ophthalmol 2021; 35:21-28. [PMID: 34667928 PMCID: PMC8486037 DOI: 10.4103/1319-4534.325777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 11/11/2022] Open
Abstract
PURPOSE: The aim of this work is to determine and compare the distribution and influence of higher-order aberrations (HOAs) both clinically and experimentally between different refractive errors. METHODS: Commercially available Shack–Hartmann aberrometer was employed to measure the HOA clinically in human eyes. Experimentally, HOA was measured in a model eye by simulating various refractive errors by constructing an aberrometer based on the same Shack Hartmann principle. One-way analyses of variance and simple regression were employed to analyze the distribution and influence of HOA among various refractive errors. RESULTS: A total of 100 eyes were clinically measured for aberrations, of which 35, 50, and 15 eyes were emmetropes, myopes, and hyperopes, respectively. Out of the total root mean square (RMS) value, the HOAs found in the human eyes were 23%, 7%, and 26% and in the model eye, it was 20%, 8%, and 10% between emmetropes, myopes, and hyperopes, respectively. The mean higher-order RMS was almost similar between the groups and among various refractive errors. There was no statistical significance between the individual Zernikes except for the coma in both human and model eyes. CONCLUSION: The mean HOA is similar amidst the different refractive errors. The presence of 23% HOA in emmetropes signifies that larger part of the human eye is capable of complying with HOA without compromising the image quality. This work signifies that HOA does not play an important role in image clarity for human eyes with regular refractive surface unlike irregular refractive surfaces.
Collapse
Affiliation(s)
- Venkataramana Kalikivayi
- Department of Optometry, Ahalia School of Optometry, Palakkad, Kerala, India.,Department of Mathematics, SASTRA University, Thanjavur, Tamil Nadu, India.,Department of Optometry, Elite School of Optometry, Indian Institute of Technology, Madras, Chennai, Tamil Nadu, India, India
| | - Lavanya Kalikivayi
- Department of Optometry, Ahalia School of Optometry, Palakkad, Kerala, India
| | - A R Ganesan
- Department of Physics, Applied Optics Laboratory, Indian Institute of Technology, Madras, Chennai, Tamil Nadu, India
| |
Collapse
|
4
|
Shneor E, Millodot M, Avraham O, Amar S, Gordon‐shaag A. Clinical evaluation of the L80 autorefractometer. Clin Exp Optom 2021; 95:66-71. [DOI: 10.1111/j.1444-0938.2011.00644.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
- Einat Shneor
- Department of Optometry, Hadassah Academic College, Jerusalem, Israel
| | - Michel Millodot
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China, E‐mail:
| | - Ortal Avraham
- Department of Optometry, Hadassah Academic College, Jerusalem, Israel
| | - Shany Amar
- Department of Optometry, Hadassah Academic College, Jerusalem, Israel
| | | |
Collapse
|
5
|
Repeatability of Aberrometry-Based Automated Subjective Refraction in Healthy and Keratoconus Subjects. J Ophthalmol 2021; 2020:4831298. [PMID: 33489331 PMCID: PMC7803284 DOI: 10.1155/2020/4831298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/13/2020] [Accepted: 10/19/2020] [Indexed: 01/10/2023] Open
Abstract
Purpose To compare the intersession repeatability of the Eye Refract, a new instrument to perform aberrometry-based automated subjective refraction, on healthy and keratoconus subjects. Materials and Methods A cross-sectional and randomized study was performed. A total of 64 participants were evaluated in the study, selecting one eye per participant randomly. The sample was divided into two different groups: 33 healthy subjects (38.85 ± 13.21 years) and 31 with keratoconus (37.29 ± 11.37 years). Three refractions per participant with the Eye Refract were performed on three different days, without cycloplegia. The repeatability analysis of refractive variables (M, J0, and J45), binocular corrected distance visual acuity (BCDVA), and spent time in refraction was performed in terms of repeatability (Sr), its 95% confidence interval (r), and intraclass correlation coefficient (ICC). Results There were no statistically significant differences (P ≥ 0.05) between sessions in both groups for all refractive variables (M, J0, and J45) and BCDVA. Spent time in refraction was reduced as the sessions went by (P < 0.05). The Eye Refract was more repeatable for refractive errors assessment in healthy subjects (M : Sr = 0.27 D; J0 : Sr = 0.09 D; J45 : Sr = 0.06 D) compared to those with keratoconus (M : Sr = 0.65 D; J0 : Sr = 0.29 D; J45 : Sr = 0.24 D), while it was similar for BCDVA. Conclusions The Eye Refract offered better repeatability to assess refractive errors in healthy subjects compared to those with keratoconus. Despite measurements being also consistent in keratoconus subjects, they should be treated with caution in clinical practice.
Collapse
|
6
|
Comparison of Two Wavefront Autorefractors: Binocular Open-Field versus Monocular Closed-Field. J Ophthalmol 2020; 2020:8580471. [PMID: 31976087 PMCID: PMC6961603 DOI: 10.1155/2020/8580471] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/14/2019] [Accepted: 12/17/2019] [Indexed: 01/10/2023] Open
Abstract
Purpose To evaluate the agreement and repeatability between a new commercially available binocular open-field wavefront autorefractor, as part of the Eye Refract system, and a monocular closed-field wavefront autorefractor (VX110). Methods A cross-sectional, randomized, and single-masked study was performed. Ninety-nine eyes of 99 healthy participants (37.22 ± 18.04 years, range 8 to 69 years) were randomly analyzed. Three measurements with the Eye Refract and the VX110 were taken on three different days, under noncycloplegic conditions. Mean spherical equivalent (MSE), cylindrical vectors (J0 and J45), and binocular corrected distance visual acuity (BCDVA) were compared between both autorefractors. An intersession repeatability analysis was done considering the values of repeatability (Sr) and its 95% limit (r). Results The VX110 showed more negative values (P < 0.001) in terms of MSE in comparison with the Eye Refract (0.20 D). Regarding cylindrical vectors, J45 showed statistically significant differences (P=0.001) between both wavefront autorefractors, but they were not clinically relevant (<0.05 D). In BCDVA, there were no statistically significant differences (P=0.667) between both wavefront autorefractors. Additionally, the Eye Refract was more repeatable than the VX110 in terms of both MSE (SrEYE REFRACT = 0.21 D, SrVX110 = 0.53 D) and J0 (SrEYE REFRACT = 0.12 D, SrVX110 = 0.35 D). Conclusions The Eye Refract provided enough accuracy and reliability to estimate refractive errors in different age groups, achieving better results than the VX110. Therefore, the Eye Refract proved to be a useful autorefractor to be incorporated into clinical practice.
Collapse
|
7
|
Cook WH, McKelvie J, Wallace HB, Misra SL. Comparison of higher order wavefront aberrations with four aberrometers. Indian J Ophthalmol 2019; 67:1030-1035. [PMID: 31238402 PMCID: PMC6611280 DOI: 10.4103/ijo.ijo_1464_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Purpose: To evaluate the agreement of selected higher order aberration measurements between aberrometers based on three different wavefront technologies. Methods: Twenty-three eyes of 23 participants were compared between Zywave, OPD-Scan III, and iDesign aberrometers, for total ocular aberrations. Participants were between 19 and 69 years of age, and exclusion criteria were previous ocular surgery or trauma, contact lens wear within the preceding 2 weeks, and ocular or systemic disease. Corneal aberrations were compared between the OPD-Scan III and GALILEI™ G2 aberrometers. Zernike coefficients of vertical and oblique trefoil, vertical and horizontal coma, and spherical aberration were analyzed in R software. Results: In all, 276 scans were captured in total, with a male-to-female ratio of 11:12. Total ocular vertical coma [mean difference (MD) = 0.026 μm, P < 0.005], vertical trefoil (MD = 0.033 μm, P < 0.05), and spherical aberration (MD = 0.022 μm, P < 0.05) differed significantly between the iDesign and OPD-Scan III. Differences in total vertical (MD = 0.072 μm, P < 0.05) and oblique trefoil (MD = 0.058 μm, P < 0.05) were demonstrated between the Zywave and OPD-Scan III, and spherical aberration (MD = 0.030 μm, P < 0.005) between iDesign and Zywave. iDesign corneal horizontal coma (MD = 0.025 μm, P < 0.05) and spherical aberration (MD = 0.043 μm, P < 0.005) measurements were significantly different between the GALILEI™ G2 and the OPD-Scan III. Conclusion: Zywave, iDesign, and OPD-Scan III, and GALILEI™ G2 and OPD-Scan III may be used interchangeably for their total ocular and corneal wavefront functions, respectively; however, care must be taken if using these devices for guiding ablation or monitoring corneal disease.
Collapse
Affiliation(s)
- William H Cook
- Department of Ophthalmology and New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - James McKelvie
- Department of Ophthalmology and New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Henry B Wallace
- Department of Ophthalmology and New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Stuti L Misra
- Department of Ophthalmology and New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| |
Collapse
|
8
|
Plaza-Puche AB, Salerno LC, Versaci F, Romero D, Alio JL. Clinical evaluation of the repeatability of ocular aberrometry obtained with a new pyramid wavefront sensor. Eur J Ophthalmol 2018; 29:585-592. [PMID: 30516061 DOI: 10.1177/1120672118816060] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To evaluate the intrasubject repeatability of the ocular aberrometry obtained with a new ocular pyramidal aberrometer technology in a sample of normal eyes. METHODS A total of 53 healthy eyes of 53 subjects with ages ranging from 18 to 45 years were included in this study. In all cases, three consecutive acquisitions were obtained. Intrasubject repeatability of the measurements with a pyramidal aberrometer was calculated. Intrasubject repeatability for 4.0- and 6.0-mm pupils was evaluated within the subject standard deviation (Sw) and intraclass correlation coefficient. RESULTS Low values of the Sw and intraclass correlation coefficient outcomes close to 1 were observed for the sphere and cylinder at 3.0-mm pupil size. Most low Sw and intraclass correlation coefficient values close to 1 were observed for total, low-order aberrations and higher-order aberrations root mean square and for each Zernike coefficient analysis (intraclass correlation coefficient ⩾0.798) at 4.0-mm pupil size, with more limited outcomes for the aberrometric coefficient of Z(4, 4) with an intraclass correlation coefficient of 0.683. For a 6.0 mm pupil diameter, low Sw and intraclass correlation coefficient values close to 1 were observed for all aberrometric parameters or Zernike coefficients analyzed (intraclass correlation coefficient ⩾0.850). CONCLUSION The new pyramidal aberrometer Osiris provides repeatable and consistent measurements of ocular aberrometry measurements in normal eyes.
Collapse
Affiliation(s)
| | | | - Francesco Versaci
- R&D Department, Costruzione Strumenti Oftalmici (CSO), Florence, Italy
| | - Daniel Romero
- Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain
| | - Jorge L Alio
- Vissum, Alicante, Spain.,Division of Ophthalmology, Universidad Miguel Hernández, Alicante, Spain
| |
Collapse
|
9
|
Gordon-Shaag A, Piñero DP, Kahloun C, Markov D, Parnes T, Gantz L, Shneor E. Validation of refraction and anterior segment parameters by a new multi-diagnostic platform (VX120). JOURNAL OF OPTOMETRY 2018; 11:242-251. [PMID: 29526690 PMCID: PMC6147758 DOI: 10.1016/j.optom.2017.12.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 12/17/2017] [Accepted: 12/27/2017] [Indexed: 05/30/2023]
Abstract
BACKGROUND The VX120 (Visionix Luneau, France) is a novel multi-diagnostic platform that combines Hartmann-Shack based autorefraction, Placido-disk based corneal-topography and anterior segment measurements made with a stationary-Scheimpflug camera. We investigate the agreement between different parameters measured by the VX120 with accepted or gold-standard techniques to test if they are interchangeable, as well as to evaluate the repeatability and reproducibility. METHODS The right-eyes of healthy subjects were included in the study. Autorefraction of the VX120 was compared to subjective refraction. Agreement of anterior segment parameters was compared to the Sirius (CSO, Italy) including autokeratometry, central corneal thickness (CCT), iridiocorneal angle (IA). Inter and intra-test repeatability of the above parameters was assessed. Results were analyzed using Bland and Altman analyses. RESULTS A total of 164 eyes were evaluated. The mean difference between VX120 autorefraction and subjective refraction for sphere, spherical equivalent (SE), and cylinder was 0.01±0.43D, 0.14±0.47D, and -0.26±0.30D, respectively and high correlation was found to all parameter (r>0.75) except for J45 (r=0.61). The mean difference between VX120 and the Sirius system for CCT, IA, and keratometry (k1 and k2) was -3.51±8.64μm, 7.6±4.2°, 0.003±0.06mm and 0.004±0.04mm, respectively and high correlation was found to all parameter (r>0.97) except for IA (r=0.67). Intrasession repeatability of VX120 refraction, CCT, IA and keratometry yielded low within-subject standard deviations. Inter-session repeatability showed no statistically significant difference for most of the parameters measured. CONCLUSIONS The VX120 provides consistent refraction and most anterior segment measurements in normal healthy eyes, with high levels of intra and inter-session repeatability.
Collapse
Affiliation(s)
- Ariela Gordon-Shaag
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel
| | - David P Piñero
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Spain
| | - Cyril Kahloun
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel
| | - David Markov
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel
| | - Tzadok Parnes
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel
| | - Liat Gantz
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel
| | - Einat Shneor
- Department of Optometry and Vision Science, Hadassah Academic College, Jerusalem, Israel.
| |
Collapse
|
10
|
Lau JK, Vincent SJ, Collins MJ, Cheung SW, Cho P. Ocular higher-order aberrations and axial eye growth in young Hong Kong children. Sci Rep 2018; 8:6726. [PMID: 29712928 PMCID: PMC5928153 DOI: 10.1038/s41598-018-24906-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 04/10/2018] [Indexed: 12/12/2022] Open
Abstract
This retrospective longitudinal analysis aimed to investigate the association between ocular higher-order aberrations (HOAs) and axial eye growth in Hong Kong children. Measures of axial length and ocular HOAs under cycloplegia were obtained annually over a two-year period from 137 subjects aged 8.8 ± 1.4 years with mean spherical equivalent refraction of -2.04 ± 2.38 D. A significant negative association was observed between the RMS of total HOAs and axial eye growth (P = 0.03), after adjusting for other significant predictors of axial length including age, sex and refractive error. Similar negative associations with axial elongation were found for the RMS of spherical aberrations ([Formula: see text] and [Formula: see text] combined) (P = 0.037). Another linear mixed model also showed that greater levels of vertical trefoil [Formula: see text], primary spherical aberration [Formula: see text] and negative oblique trefoil [Formula: see text] were associated with slower axial elongation and longer axial length (all P < 0.05). These findings support the potential role of HOAs, image quality and a vision-dependent mechanism in childhood eye growth.
Collapse
Affiliation(s)
- Jason K Lau
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
| | - Stephen J Vincent
- Contact Lens and Visual Optics Laboratory, School of Optometry and Visual Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Michael J Collins
- Contact Lens and Visual Optics Laboratory, School of Optometry and Visual Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Sin-Wan Cheung
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Pauline Cho
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| |
Collapse
|
11
|
Oberholzer M, Gillan WD, Rubin A. Higher order aberrations of the eye: Part two. AFRICAN VISION AND EYE HEALTH 2016. [DOI: 10.4102/aveh.v75i1.335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
This article is the second in a series of two articles, which provides a discussion of the factors that may possibly contribute to variable results when wavefront aberrations of the human eye are measured. Some of the factors discussed in this article are the influences that refractive errors (specifically myopia and astigmatism), pupil diameter, accommodation of the crystalline lens, age, mydiatric drops and the integrity of the tear film may have on these wavefront measurements. The first article in the series explained the general principles of higher order aberrations (HOAs), as well as HOAs of importance in the eye and the measuring apparatus used to measure HOAs of the eye.Keywords: wavefront aberrations; aberrometry
Collapse
|
12
|
Oberholzer M, Gillan WD, Rubin A. Higher order aberrations of the eye: Part one. AFRICAN VISION AND EYE HEALTH 2016. [DOI: 10.4102/aveh.v75i1.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
This article is the first in a series of two articles that provide a comprehensive literature review of higher order aberrations (HOAs) of the eye. The present article mainly explains the general principles of such HOAs as well as HOAs of importance, and the measuring apparatus used to measure HOAs of the eye. The second article in the series discusses factors contributing to variable results in measurements of HOAs of the eye.Keywords: Higher order aberrations; wavefront aberrations; aberrometer
Collapse
|
13
|
Comparison of Refractive Error Measures by the IRX3 Aberrometer and Autorefraction. Optom Vis Sci 2014; 91:1183-90. [PMID: 25192432 DOI: 10.1097/opx.0000000000000379] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
14
|
|
15
|
Cade F, Cruzat A, Paschalis EI, Espírito Santo L, Pineda R. Analysis of four aberrometers for evaluating lower and higher order aberrations. PLoS One 2013; 8:e54990. [PMID: 23349995 PMCID: PMC3551914 DOI: 10.1371/journal.pone.0054990] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 12/19/2012] [Indexed: 11/18/2022] Open
Abstract
PURPOSE To compare the measurements of lower and higher order aberrations (HOA) of 4 commonly used aberrometers. SETTING Massachusetts Eye & Ear Infirmary, Boston, USA. DESIGN Prospective, cross-sectional study, in a controlled, single-blinded fashion. METHODS Multiple readings were obtained in 42 eyes of 21 healthy volunteers, at a single visit, with each of the following aberrometers: Alcon LADARWave®, Visx WaveScan®, B & L Zywave®, and Wavelight Allegro Analyzer®. Results were compared and analyzed in regards to the lower and HOA, to the different wavefront sensing devices and software, Tscherning and Hartmann-Shack and between the Fourier and Zernike algorithms. Statistical analysis included Bland-Altman plots, Intraclass Correlation Coefficient (ICC), multiple comparison tests with Analysis of Variance and Kruskal-Wallis. Significant level was set to p<0.05 and alpha level correction was adjusted under the Bonferroni criteria. RESULTS Most measurements of all 4 aberrometers were comparable. However, statistically significant differences were found between the aberrometers in total HOA (tHOA), spherical aberration (SA), horizontal coma and astigmatism (2,2). LADARwave and Wavescan showed significant differences in tHOA (P<0.001, ICC = 0.549, LoA = 0.19±0.5) and in SA (P<0.001, ICC = 0.733, LoA = 0.16±0.37). Wavescan showed a significant difference compared to Zywave (p<0.001, ICC = 0.920, LoA = 0.09±0.13) in SA. Comparisons between Allegro Analyzer and Zywave demonstrated significant differences in both Horizontal Coma (3,1) (p<0.001, ICC = -0.207, LoA = -0.15±0.48) and Astigmatism (2,2) (P = 0.003, ICC = -0.965, LoA = 0.2±2.5). Allegro Analyzer also differed from Wavescan in Horizontal Coma (3,1) (P<0.001, ICC = 0.725, LoA = -0.07±0.25). CONCLUSIONS Although some measurements were comparable predominately in the lower order aberrations, significant differences were found in the tHOA, SA, horizontal coma and astigmatism. Our analysis suggests that sensor design contributes to agreement in lower order aberrations, and Fourier and Zernike expansion might disagree in higher order aberrations. Therefore, comparison between aberrometers was generally possible with some exceptions in higher order measurements.
Collapse
Affiliation(s)
- Fabiano Cade
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrea Cruzat
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Eleftherios I. Paschalis
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| | - Lilian Espírito Santo
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Roberto Pineda
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America
| |
Collapse
|
16
|
López-Miguel A, Maldonado MJ, Belzunce A, Barrio-Barrio J, Coco-Martín MB, Nieto JC. Precision of a commercial hartmann-shack aberrometer: limits of total wavefront laser vision correction. Am J Ophthalmol 2012; 154:799-807.e5. [PMID: 22902046 DOI: 10.1016/j.ajo.2012.04.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 04/26/2012] [Accepted: 04/26/2012] [Indexed: 11/26/2022]
Abstract
PURPOSE To assess the intrasession and intersession precision of higher-order aberrations (HOAs) measured using a commercial Hartmann-Shack wavefront sensor (Zywave; Bausch & Lomb) in refractive surgery candidates. DESIGN Prospective, experimental study of a device. METHODS To analyze intrasession repeatability, 1 experienced examiner measured 30 healthy eyes 5 times successively. To study intersession reproducibility, the same clinician obtained measurements from another 30 eyes in 2 consecutive sessions at the same time of day 1 week apart. RESULTS For intrasession repeatability, excellent intraclass correlation coefficients (ICCs) were obtained for total ocular aberrations, total HOAs, and second-order terms (ICC, > 0.94). The ICCs for third-order terms also were high (ICCs, > 0.87); however, fourth-order ICCs varied from 0.71 to 0.90 (Z(4)(0) = 0.90); and fifth-order ICCs were less than 0.85. For intersession reproducibility, only total ocular aberrations, total ocular HOAs, second-order terms, Z(4)(0), Z(3)(1), and Z(3-)(3) had ICCs of 0.90 or more. Bland-Altman analysis showed that the limits of agreement (were clinically too wide for most higher-order Zernike terms, especially for the third-order terms (> 0.21 μm). CONCLUSIONS Total ocular aberrations, total HOAs, and second-order terms can be measured reliably by Zywave aberrometry without anatomic recognition. Third-order terms and Z(4)(0) are repeatable, but not as reproducible between visits. Fourth-order terms, except for Z(4)(0), and fifth-order terms are not sufficiently reliable for clinical decision making or treatment. Because the variability of Zywave can be a major limitation of a truly successful wavefront-guided excimer laser procedure, surgeons should consider treating HOA magnitudes that are more than the intrasession repeatability values (2.77 × S(w)) as those presented in this study.
Collapse
|
17
|
Fotouhi A, Hashemi H, Shariati M, Emamian MH, Yazdani K, Jafarzadehpur E, Koohian H, Khademi MR, Hodjatjalali K, Kheirkhah A, Chaman R, Malihi S, Mirzaii M, Khabazkhoob M. Cohort profile: Shahroud Eye Cohort Study. Int J Epidemiol 2012; 42:1300-8. [PMID: 23081880 DOI: 10.1093/ije/dys161] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Shahroud Eye Cohort Study was set up to determine the prevalence and incidence of visual impairment and major eye conditions in the 40-64-year-old population of Shahroud as a Middle Eastern population. The first phase of the study was conducted in 2009-10. Using random cluster sampling, 6311 Shahroud inhabitants were invited for ophthalmologic examinations; of these, 5190 participants completed phase 1 (participation rate of 82.2%). All participants were interviewed to collect data on participants' demographics, occupation status, socioeconomic status, history of smoking, and medical and ophthalmic history, as well as history of medication, and the quality and duration of their insurance. DNA and plasma samples, as well as four dots of whole blood were collected from participants. Extensive optometric and ophthalmologic examinations were performed for each participant, including lensometry of current glasses, testing near and far visual acuity; determining objective and subjective refraction; eye motility; cycloplegic refraction; colour vision test; slit-lamp biomicroscopy and intraocular pressure measurement; direct and indirect fundoscopy; perimetry test; ocular biometry; corneal topography; lens and fundus photography; and the Schirmer's (1008 participants) and tear breakup time tests (1013 participants). The study data are available for collaborative research at Noor Ophthalmology Research Center, Tehran, Iran.
Collapse
Affiliation(s)
- Akbar Fotouhi
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran, Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran, Department of Public Health, Shahroud University of Medical Sciences, Shahroud, Iran, Education Development Center, Tehran University of Medical Sciences, Tehran, Iran, Department of Optometry, Tehran University of Medical Sciences, Tehran, Iran and Faculty of Medical Sciences, Open University of Shahroud, Shahroud, Iran
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
|
19
|
McAlinden C, Khadka J, Pesudovs K. Statistical methods for conducting agreement (comparison of clinical tests) and precision (repeatability or reproducibility) studies in optometry and ophthalmology. Ophthalmic Physiol Opt 2011; 31:330-8. [PMID: 21615445 DOI: 10.1111/j.1475-1313.2011.00851.x] [Citation(s) in RCA: 306] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The ever-expanding choice of ocular metrology and imaging equipment has driven research into the validity of their measurements. Consequently, studies of the agreement between two instruments or clinical tests have proliferated in the ophthalmic literature. It is important that researchers apply the appropriate statistical tests in agreement studies. Correlation coefficients are hazardous and should be avoided. The 'limits of agreement' method originally proposed by Altman and Bland in 1983 is the statistical procedure of choice. Its step-by-step use and practical considerations in relation to optometry and ophthalmology are detailed in addition to sample size considerations and statistical approaches to precision (repeatability or reproducibility) estimates.
Collapse
Affiliation(s)
- Colm McAlinden
- NH&MRC Centre for Clinical Eye Research, Department of Optometry and Vision Science, Flinders Medical Centre and Flinders University of South Australia, Adelaide, Australia.
| | | | | |
Collapse
|
20
|
Piñero DP, Juan JT, Alió JL. Intrasubject repeatability of internal aberrometry obtained with a new integrated aberrometer. J Refract Surg 2010; 27:509-17. [PMID: 21188958 DOI: 10.3928/1081597x-20101214-01] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 11/10/2010] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the intrasubject repeatability of the internal aberrometry obtained with a new integrated aberrometer in a sample of normal eyes to assess its clinical usefulness. METHODS Twenty-six healthy eyes of 26 participants, aged 20 to 50 years, were included in the study. All eyes achieved corrected distance visual acuity of 1.0 (Snellen decimal notation) and did not undergo previous ocular surgeries. Three consecutive measurements of internal aberrations were obtained with the KR-1W system (Topcon Corp) by an experienced examiner. Intrasubject repeatability for 4- and 6-mm pupils was evaluated by the within-subject standard deviation (S(w)) and intraclass correlation coefficient (ICC). RESULTS Low values of S(w) and values of ICC close to 1 were found for the 4-mm pupil astigmatism and for several aberrometric coefficients: primary spherical aberration and higher order, third order, and trefoil root-mean-square (RMS). Significant correlations of the S(w) for the 4-mm pupil higher order aberrations RMS with the magnitude of different aberrometric coefficients were found (r≥0.611, P<.01). In addition, tetrafoil RMS for 4-mm pupils correlated significantly with the S(w) for some higher order errors (r≥0.675, P<.01). Significantly larger values of S(w) for 6-mm pupils were found for trefoil (P<.01) and secondary astigmatism RMS (P=.02). CONCLUSIONS The KR-1W provided repeatable measurements of internal astigmatism and some higher order aberrations, although consistency of such measurements appears to be limited by the level of aberration.
Collapse
Affiliation(s)
- David P Piñero
- Departamento de Optica, Universidad de Alicante, Alicante, Spain.
| | | | | |
Collapse
|