TY - JOUR
T1 - Optomechanical response of human and monkey lenses in a lens stretcher
AU - Manns, Fabrice
AU - Parel, Jean Marie
AU - Denham, David
AU - Billotte, Christian
AU - Ziebarth, Noel
AU - Borja, David
AU - Fernandez, Viviana
AU - Aly, Mohammed
AU - Arrieta, Esdras
AU - Ho, Arthur
AU - Holden, Brien
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/7
Y1 - 2007/7
N2 - PURPOSE. To quantify the forces necessary to change the shape and optical power of human and monkey lenses. METHODS. Cynomolgus monkey (n = 48; age: 3.8-11 years), rhesus monkey (n = 35; age: 0.7-17 years) and human (n = 20, age 8-70 years) eyes obtained postmortem, including the lens, capsule, zonules, ciliary body, and sclera were mounted in an optomechanical lens-stretching system. Starting at zero load, the lenses were symmetrically stretched in a stepwise fashion in 0.25- or 0.5-mm steps. The load, lens diameter, inner ciliary body diameter, and lens power were measured at each step and the diameter- and power-load responses were quantified. RESULTS. The diameter- and power-load responses were found to be linear in the physiologically relevant range of stretching. The average change in cynomolgus, rhesus, and human lens diameter, respectively, was 0.094, 0.109, and 0.069 mm/g in young lenses, and 0.069, 0.067, and 0.036, mm/g in older lenses. For the same lenses, the average change in lens power was -3.73, -2.83, and -1.22 D/g in young lenses and -2.46, -2.16, and -0.49 D/g in older lenses. CONCLUSIONS. The force necessary to change the lens diameter and lens power increases with age in human and monkey lenses. The results agree with the Helmholtz theory of accommodation and with presbyopia theories that predict that the force required to disaccommodate the lens increases with age.
AB - PURPOSE. To quantify the forces necessary to change the shape and optical power of human and monkey lenses. METHODS. Cynomolgus monkey (n = 48; age: 3.8-11 years), rhesus monkey (n = 35; age: 0.7-17 years) and human (n = 20, age 8-70 years) eyes obtained postmortem, including the lens, capsule, zonules, ciliary body, and sclera were mounted in an optomechanical lens-stretching system. Starting at zero load, the lenses were symmetrically stretched in a stepwise fashion in 0.25- or 0.5-mm steps. The load, lens diameter, inner ciliary body diameter, and lens power were measured at each step and the diameter- and power-load responses were quantified. RESULTS. The diameter- and power-load responses were found to be linear in the physiologically relevant range of stretching. The average change in cynomolgus, rhesus, and human lens diameter, respectively, was 0.094, 0.109, and 0.069 mm/g in young lenses, and 0.069, 0.067, and 0.036, mm/g in older lenses. For the same lenses, the average change in lens power was -3.73, -2.83, and -1.22 D/g in young lenses and -2.46, -2.16, and -0.49 D/g in older lenses. CONCLUSIONS. The force necessary to change the lens diameter and lens power increases with age in human and monkey lenses. The results agree with the Helmholtz theory of accommodation and with presbyopia theories that predict that the force required to disaccommodate the lens increases with age.
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U2 - 10.1167/iovs.06-1376
DO - 10.1167/iovs.06-1376
M3 - Article
C2 - 17591897
AN - SCOPUS:34548075043
VL - 48
SP - 3260
EP - 3268
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
SN - 0146-0404
IS - 7
ER -