Model of zonular forces on the lens capsule during accommodation.

Autor: Schachar RA; Department of Physics, University of Texas at Arlington, Arlington, TX, USA. ron@2ras.com., Schachar IH; North Bay Vitreoretinal Consultants, Santa Rosa, CA, USA., Kumar S; Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA, USA., Feldman EI; Rice University, Houston, TX, USA., Pierscionek BK; Faculty of Health, Medicine and Social Care, Medical Technology Research Centre, Anglia Ruskin University, Chelmsford, UK., Cosman PC; Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA, USA.
Jazyk: angličtina
Zdroj: Scientific reports [Sci Rep] 2024 Mar 11; Vol. 14 (1), pp. 5896. Date of Electronic Publication: 2024 Mar 11.
DOI: 10.1038/s41598-024-56563-8
Abstrakt: How the human eye focuses for near; i.e. accommodates, is still being evaluated after more than 165 years. The mechanism of accommodation is essential for understanding the etiology and potential treatments for myopia, glaucoma and presbyopia. Presbyopia affects 100% of the population in the fifth decade of life. The lens is encased in a semi-elastic capsule with attached ligaments called zonules that mediate ciliary muscle forces to alter lens shape. The zonules are attached at the lens capsule equator. The fundamental issue is whether during accommodation all the zonules relax causing the central and peripheral lens surfaces to steepen, or the equatorial zonules are under increased tension while the anterior and posterior zonules relax causing the lens surface to peripherally flatten and centrally steepen while maintaining lens stability. Here we show with a balloon capsule zonular force model that increased equatorial zonular tension with relaxation of the anterior and posterior zonules replicates the topographical changes observed during in vivo rhesus and human accommodation of the lens capsule without lens stroma. The zonular forces required to simulate lens capsule configuration during in vivo accommodation are inconsistent with the general belief that all the zonules relax during accommodation.
(© 2024. The Author(s).)
Databáze: MEDLINE
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