Repeatability of corneal biomechanics waveform signal parameters derived from Ocular Response Analyzer in children

Published:October 22, 2020DOI:https://doi.org/10.1016/j.clae.2020.10.003

      Abstract

      Purpose

      To investigate the repeatability of waveform signal parameters, measured with the Ocular Response Analyzer (ORA), in children.

      Methods

      Two sets of ORA measurements, with a 10-min break between them, were performed on children, aged six to <11 years old, either wearing single-vision spectacles (SVS) or orthokeratology (ortho-k) lenses. Intraclass correlation coefficients (ICCs) were used to assess agreements between two sets of measurements (37 waveform signal parameters). Bland-Altman (BA) plots were used to further analyse waveform signal parameters which had ICC 95 % confidence interval (95 % CI) between 0.50 to >0.90 (regarded as moderate to excellent agreement).

      Results

      A total of 30 participants [15 SVS, 15 ortho-k (3.6 ± 2.4 months)] completed the study. Since no significant between-group differences were detected in demographic data (p > 0.28) and all waveform signal parameters (p > 0.05), data from the two groups of participants were pooled for the analysis of repeatability. Six parameters, h2, h21, p1area, p1area1, p2area, and p2area1, achieved ICCs (95 % CI) of 0.82−0.85 (0.61−0.93). The mean (SD) of these six parameters were 372 (91), 248 (61), 4077 (854), 1762 (399), 2359 (670), and 1020 (300), respectively. Bland-Altman plots and 95 % limits of agreement (95 % LoA) showed considerable agreement for all six parameters, the mean difference (95 % LoA) were -3 (-101 to 94), -2 (-67.56–62.70), 111 (-723 to 946), 102 (-334 to 539), 25 (-718 to 768), and -3 (-350 to 343), respectively.

      Conclusions

      Six waveform signal parameters (h2, h21, p1area, p1area1, p2area, and p2area1), which represent or are related to the areas under the waveform at the peaks in the signal, had moderate to excellent agreement in children. Results of the current study provides fundamental information for further studies on the potential clinical application of these waveform signal parameters in children.

      Keywords

      To read this article in full you will need to make a payment

      References

        • Kotecha A.
        What biomechanical properties of the cornea are relevant for the clinician?.
        Surv Ophthalmol. 2007; 52: S109-14
        • Luce D.A.
        Determining in vivo biomechanical properties of the cornea with an ocular response analyzer.
        J Cataract Refract Surg. 2005; 31: 156-162
        • Jue B.
        • Maurice D.M.
        The mechanical properties of the rabbit and human cornea.
        J Biomech. 1986; 19: 847-853
        • Schwartz N.J.
        • Mackay R.S.
        • Sackman J.L.
        A theoretical and experimental study of the mechanical behavior of the cornea with application to the measurement of intraocular pressure.
        Bull Math Biophys. 1966; 28: 585-643
        • Hoeltzel D.A.
        • Altman P.
        • Buzard K.
        • Il Choe K.
        Strip extensiometry for comparison of the mechanical response of bovine, rabbit, and human corneas.
        J Biomech Eng. 1992; 114: 202-215
        • Pensyl D.
        • Sullivan-Mee M.
        • Torres-Monte M.
        • Halverson K.
        • Qualls C.
        Combining corneal hysteresis with central corneal thickness and intraocular pressure for glaucoma risk assessment.
        Eye. 2012; 26: 1349-1356
        • Herdener S.
        • Pfeifer N.
        • Lautebach S.
        • Pache M.
        Corneal hysteresis in patients with corneal pathologies.
        Acta Ophthalmol Scand. 2007; 85 (0–0)
        • Mangouritsas G.
        • Morphis G.
        • Mourtzoukos S.
        • Feretis E.
        Association between corneal hysteresis and central corneal thickness in glaucomatous and non‐glaucomatous eyes.
        Acta Ophthalmol. 2009; 87: 901-905
        • Hussnain S.A.
        • Alsberge J.B.
        • Ehrlich J.R.
        • Shimmyo M.
        • Radcliffe N.M.
        Change in corneal hysteresis over time in normal, glaucomatous and diabetic eyes.
        Acta Ophthalmol. 2015; 93: 627-630
        • Reinstein D.Z.
        • Gobbe M.
        • Archer T.J.
        Ocular biomechanics: measurement parameters and terminology.
        J Refract Surg. 2011; 6: 386-397
        • Ortiz D.
        • Piñero D.
        • Shabayek M.H.
        • Arnalich-Montiel F.
        • Alió J.L.
        Corneal biomechanical properties in normal, post-laser in situ keratomileusis, and keratoconic eyes.
        J Cataract Refract Surg. 2007; 33: 1371-1375
        • Roberts C.J.
        Concepts and misconceptions in corneal biomechanics.
        J Cataract Refract Surg. 2014; 40: 862-869
        • Garcia-Porta N.
        • Fernandes P.
        • Queiros A.
        • Salgado-Borges J.
        • Parafita-Mato M.
        • González-Méijome J.M.
        Corneal biomechanical properties in different ocular conditions and new measurement techniques.
        ISRN Ophthalmol. 2014; 2014724546
        • Kerautret J.
        • Colin J.
        • Touboul D.
        • Roberts C.
        Biomechanical characteristics of the ectatic cornea.
        J Cataract Refract Surg. 2008; 34: 510-513
        • Aoki S.
        • Murata H.
        • Matsuura M.
        • Fujino Y.
        • Nakakura S.
        • Nakao Y.
        • et al.
        The relationship between the waveform parameters from the ocular response analyzer and the progression of glaucoma.
        Ophthalmol Glaucoma. 2018; 1: 123-131
        • Ventura B.V.
        • Machado A.P.
        • Ambrósio R.
        • Ribeiro G.
        • Araújo L.N.
        • Luz A.
        • et al.
        Analysis of waveform-derived ORA parameters in early forms of keratoconus and normal corneas.
        J Refract Surg. 2013; 29: 637-643
        • Wolffsohn J.S.
        • Safeen S.
        • Shah S.
        • Laiquzzaman M.
        Changes of corneal biomechanics with keratoconus.
        Cornea. 2012; 31: 849-854
        • Luz A.
        • Fontes B.M.
        • Lopes B.
        • Ramos I.
        • Schor P.
        • Ambrósio R.
        • et al.
        ORA waveform-derived biomechanical parameters to distinguish normal from keratoconic eyes.
        Arq Bras Oftalmol. 2013; 76: 111-117
        • David V.P.
        • Stead R.E.
        • Vernon S.A.
        Repeatability of ocular response analyzer metrics: a gender-based study.
        Optom Vis Sci. 2013; 90: 691-699
        • Hon Y.
        • Cheung S.W.
        • Cho P.
        • Lam A.K.C.
        Repeatability of corneal biomechanical measurements in children wearing spectacles and orthokeratology lenses.
        Ophthalmic Physiol Opt. 2012; 32: 349-354
        • Kopito R.
        • Gaujoux T.
        • Montard R.
        • Touzeau O.
        • Allouch C.
        • Borderie V.
        • et al.
        Reproducibility of viscoelastic property and intraocular pressure measurements obtained with the Ocular Response Analyzer.
        Acta Ophthalmol. 2011; 89: e225-30
        • Wasielica-Poslednik J.
        • Berisha F.
        • Aliyeva S.
        • Pfeiffer N.
        • Hoffmann E.M.
        Reproducibility of ocular response analyzer measurements and their correlation with central corneal thickness.
        Graefes Arch Clin Exp Ophthalmol. 2010; 248: 1617-1622
        • Moreno-Montanés J.
        • Maldonado M.J.
        • García N.
        • Mendiluce L.
        • García-Gómez P.J.
        • Seguí-Gómez M.
        • et al.
        Reproducibility and clinical relevance of the ocular response analyzer in nonoperated eyes: corneal biomechanical and tonometric implications.
        Investig Ophthalmol Vis Sci. 2008; 49: 968-974
        • Kynigopoulos M.
        • Schlote T.
        • Kotecha A.
        • Tzamalis A.
        • Pajic B.
        • Haefliger I.
        Repeatability of intraocular pressure and corneal biomechanical properties measurements by the ocular response analyser.
        Klin Monbl Augenheilkd. 2008; 225: 357-360
        • Kotecha A.
        • Elsheikh A.
        • Roberts C.R.
        • Zhu H.
        • Garway-Heath D.F.
        Corneal thickness- and age-related biomechanical properties of the cornea measured with the ocular response analyzer.
        Invest Ophthalmol Vis Sci. 2006; 47: 5337-5347
        • Landoulsi H.
        • Saad A.
        • Haddad N.M.N.
        • Guilbert E.
        • Gatinel D.
        Repeatability of ocular response analyzer waveform parameters in normal eyes and eyes after refractive surgery.
        J Refract Surg. 2013; 29: 709-714
        • Wong Y.Z.
        • Lam A.K.C.C.
        Influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis and corneal resistance factor.
        Clin Exp Optom. 2011; 94: 418-424
        • Bujang M.A.
        • Baharum N.
        A simplified guide to determination of sample size requirements for estimating the value of intraclass correlation coefficient: a review.
        Arch Orofac Sci. 2017; 12: 1-11
        • AKCC Lam
        • Chen D.
        • Tse J.
        The usefulness of waveform score from the ocular response analyzer.
        Optom Vis Sci. 2010; 87: 105-199
        • Koo T.K.
        • Li M.Y.
        A guideline of selecting and reporting intraclass correlation coefficients for reliability research.
        J Chiropr Med. 2016; 15: 155-163
        • Bland J.M.
        • Altman D.G.
        Statistics notes: measurement error.
        BMJ. 1996; 312: 1654
        • Bland J.M.
        • Altman D.G.
        Measuring agreement in method comparison studies.
        Stat Methods Med Res. 1999; 8: 135-160
        • Landis J.R.
        • Koch G.G.
        The measurement of observer agreement for categorical data.
        Biometrics. 1977; 33: 159-174
        • Spoerl E.
        • Terai N.
        • Scholz F.
        • Raiskup F.
        • Pillunat L.E.
        Detection of biomechanical changes after corneal cross-linking using ocular response analyzer software.
        J Refract Surg. 2011; 27: 452-457
        • Wan K.
        • Cheung S.W.
        • Wolffsohn J.S.
        • Orr J.B.
        • Cho P.
        Role of corneal biomechanical properties in predicting of speed of myopic progression in children wearing orthokeratology lenses or single-vision spectacles.
        BMJ Open Ophthalmol. 2018; 3e000204
        • Greene P.R.
        Mechanical considerations in myopia: relative effects of accommodation, convergence, intraocular pressure, and the extraocular muscles.
        Optom Vis Sci. 1980; 57: 902-914
        • Read S.A.
        • Collins M.J.
        • Annis‐Brown T.
        • Hayward N.M.
        • Lillyman K.
        • Sherwin D.
        • et al.
        The short‐term influence of elevated intraocular pressure on axial length.
        Ophthalmic Physiol Opt. 2011; 31: 398-403
        • Leydolt C.
        • Findl O.
        • Drexler W.
        Effects of change in intraocular pressure on axial eye length and lens position.
        Eye. 2008; 22: 657
        • Ostrin L.A.
        • Jnawali A.
        • Carkeet A.
        • Patel N.B.
        Twenty-four hour ocular and systemic diurnal rhythms in children.
        Ophthalmic Physiol Opt. 2019; 39: 358-369
        • Harper A.R.
        • Summers J.A.
        The dynamic sclera: extracellular matrix remodeling in normal ocular growth and myopia development.
        Exp Eye Res. 2015; 133: 100-111
        • Chen D.
        • Lam A.K.C.
        • Cho P.
        A pilot study on the corneal biomechanical changes in short-term orthokeratology.
        Ophthalmic Physiol Opt. 2009; 29: 464-471
        • Lam A.K.C.
        • Hon Y.
        • Leung S.Y.Y.
        • Shu-Ho L.
        • Chong J.
        • Lam D.C.C.
        Association between long-term orthokeratology responses and corneal biomechanics.
        Sci Rep. 2019; 9: 1-9
        • Bak-Nielsen S.
        • Pedersen I.B.
        • Ivarsen A.
        • Hjortdal J.
        Repeatability, reproducibility, and age dependency of dynamic Scheimpflug-based pneumotonometer and its correlation with a dynamic bidirectional pneumotonometry device.
        Cornea. 2015; 34: 71-77
        • Nemeth G.
        • Hassan Z.
        • Csutak A.
        • Szalai E.
        • Berta A.
        • Modis Jr L.
        Repeatability of ocular biomechanical data measurements with a Scheimpflug-based noncontact device on normal corneas.
        J Refract Surg. 2013; 29: 558-563
        • Chen X.
        • Stojanovic A.
        • Hua Y.
        • Eidet J.R.
        • Hu D.
        • Wang J.
        • et al.
        Reliability of corneal dynamic scheimpflug analyser measurements in virgin and post-PRK eyes.
        PLoS One. 2014; 9e109577