Lockington, D., Wang, Z., Qi, N., Malyugin, B., Cai, L., Wang, C., Tang, H., Ramaesh, K. and Luo, X. (2020) Modelling floppy iris syndrome and the impact of pupil size and ring devices on iris displacement. Eye, 34(12), pp. 2227-2234. (doi: 10.1038/s41433-020-0782-7) (PMID:32020061)
![[img]](https://eprints.gla.ac.uk/style/images/fileicons/text.png) |
Text
210125.pdf - Published Version Available under License Creative Commons Attribution. 1MB |
Abstract
INTRODUCTION:The aim of this paper was to further develop a previously described finite element model which equates clinical iris billowing movements with mechanical buckling behaviour, simulating floppy iris syndrome. We wished to evaluate the impact of pupil dilation and mechanical devices on normal iris and floppy iris models. METHODS:Theoretical mathematical modelling and computer simulations were used to assess billowing/buckling patterns of the iris under loading pressures for the undilated and dilated normal iris, the undilated and dilated floppy iris, and additionally with a mechanical ring device. RESULTS:For the normal iris, billowing/buckling occurred at a critical pressure of 19.92 mmHg for 5 mm pupil size, which increased to 28.00 mmHg (40.56%) with a 7 mm pupil. The Malyugin ring device significantly increased critical initiating buckling pressures in the normal iris scenario, to 34.58 mmHg (73.59%) for 7 mm ring with boundary conditions I (BC I) and 34.51 mmHg (73.24%) with BC II. For the most floppy iris modelling (40% degradation), initiating buckling value was 18.04 mmHg (-9.44%), which increased to 28.39 mmHg (42.52%) with the 7 mm ring. These results were much greater than for normal undilated iris without restrictive mechanical expansion (19.92 mmHg). CONCLUSION:This simulation demonstrates that pupil expansion devices inhibit iris billowing even in the setting of floppy iris syndrome. Our work also provides a model to further investigate the impact of pupil size or pharmacological interventions on anterior segment conditions affected by iris position.
| Item Type: | Articles |
|---|---|
| Additional Information: | Also funded by the Research Grants Council of Hong Kong (GRF 15249316), the National Natural Science Foundation of China (11902181, 11871399), and the Natural Science Foundation of Shandong Province (No.ZR2019QA014). |
| Status: | Published |
| Refereed: | Yes |
| Glasgow Author(s) Enlighten ID: | Luo, Professor Xiaoyu and Qi, Dr Nan and Ramaesh, Dr Kanna and Cai, Dr Li |
| Authors: | Lockington, D., Wang, Z., Qi, N., Malyugin, B., Cai, L., Wang, C., Tang, H., Ramaesh, K., and Luo, X. |
| College/School: | College of Science and Engineering > School of Mathematics and Statistics > Mathematics |
| Journal Name: | Eye |
| Publisher: | Nature Research |
| ISSN: | 0950-222X |
| ISSN (Online): | 1476-5454 |
| Published Online: | 04 February 2020 |
| Copyright Holders: | Copyright © 2020 The Authors |
| First Published: | First published in Eye 34(12): 2227-2234 |
| Publisher Policy: | Reproduced under a Creative Commons licence |
University Staff: Request a correction | Enlighten Editors: Update this record
Altmetric
Altmetric