In vivo measures of anterior scleral resistance in humans with rebound tonometry


Purpose: To measure regional variations in anterior scleral resistance (ASR) using a ballistic rebound tonometer (RBT) and examine whether the variations are significantly affected by ethnicity and refractive error (RE). Methods: ASR was measured using a RBT (iCare TA01) following calibration against the biomechanical properties of agarose biogels. Eight scleral regions (nasal, temporal, superior, inferior, inferior-nasal, inferior-temporal, superior-nasal and superior-temporal) were measured at locations 4mm from the limbus. Subjects were 130 young adults comprising three ethnic groups whose RE distributions [MSE (D) ± S.D.] incorporated individuals categorised as without-myopia (NM; MSE ≥ −0.50) and with-myopia (WM; MSE < −0.50); British-White (BW): 26 NM + 0.52 ± 1.15D; 22 WM −3.83 ± 2.89D]; British-South-Asian (BSA): [9 NM + 0.49 ± 1.06D; 11 WM −5.07 ± 3.76D; Hong-Kong-Chinese (HKC): [11 NM + 0.39 ± 0.66D; 49 WM −4.46 ± 2.70D]. Biometric data were compiled using cycloplegic open-field autorefraction and the Zeiss IOLMaster. Two- and three-way repeated measures analysis of variances (anovas) tested regional differences for RBT values across both refractive status and ethnicity whilst stepwise forward multiple linear regression was used as an exploratory test. Results: Significant regional variations in ASR were identified for the BW, BSA and HKC (p < 0.001) individuals; superior-temporal region showed the lowest levels of resistance whilst the inferior-nasal region the highest. Compared to the BW and BSA groups, the HKC subjects displayed a significant increase in mean resistance for each respective region (p < 0.001). With the exception of the inferior region, ethnicity was found to be the chief predictor for variation in the scleral RBT values for all other regions. Mean RE group differences were insignificant. Conclusions: The novel application of RBT to the anterior sclera confirm regional variation in ASR. Greater ASR amongst the HKC group than the BW and BSA individuals suggests that ethnic differences in anterior scleral biomechanics may exist.

Publication DOI:
Divisions: College of Health & Life Sciences > School of Optometry > Optometry
College of Health & Life Sciences
College of Health & Life Sciences > School of Optometry > Optometry & Vision Science Research Group (OVSRG)
College of Health & Life Sciences > School of Optometry > Vision, Hearing and Language
Additional Information: © 2020 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Uncontrolled Keywords: anterior,rebound,resistance,sclera,tonometry,Ophthalmology,Optometry,Sensory Systems
Publication ISSN: 1475-1313
Last Modified: 17 Jun 2024 07:49
Date Deposited: 15 Jun 2020 09:23
Full Text Link:
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
https://onlinel ... .1111/opo.12695 (Publisher URL)
PURE Output Type: Article
Published Date: 2020-07-01
Published Online Date: 2020-06-03
Accepted Date: 2020-04-14
Authors: Buckhurst, Hetal D.
Gilmartin, Bernard
Lam, Andrew
Cubbidge, Robert P. (ORCID Profile 0000-0002-7851-1375)
Logan, Nicola S. (ORCID Profile 0000-0002-0538-9516)



Version: Published Version

License: Creative Commons Attribution

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