Visual Psychophysics and Physiological Optics Age-Related Changes in the Anterior Segment Biometry During Accommodation

PURPOSE We investigated the dynamic response of human accommodative elements as a function of age during accommodation using synchronized spectral domain optical coherence tomography devices (SD-OCT). METHODS We enrolled 33 left eyes from 33 healthy subjects (age range, 20-39 years, 17 males and 16 females). Two SD-OCT devices were synchronized to simultaneously image the anterior segment through pupil and the ciliary muscle during 6.00 diopter (D) accommodation for approximately 3.7 seconds in two repeated measurements. The anterior segment parameters included the lens thickness (LT), radius of curvature of the lens anterior surface (LAC), maximum thickness of ciliary muscle (CMTMAX), and anterior length of the ciliary muscle (CMAL). A first-order exponential equation was used to fit the dynamic changes during accommodation. The age-related changes in the dynamic response and their relationship were calculated and compared. RESULTS The amplitude (r = -0.40 and 0.53 for LT and LAC, respectively) and peak velocity (r = -0.65 and 0.71 for LT and LAC, respectively) of the changes in LT and LAC significantly decreased with age (P < 0.05), whereas the parameters of the ciliary muscle remained unchanged (P > 0.05), except for the peak velocity of the CMAL (r = 0.44, P = 0.01). The difference in the time constant between the lens reshaping (LT and LAC) and CMTMAX increased with age (r = 0.46 and 0.57 for LT and LAC, respectively, P < 0.01). The changes in LT and LAC per millimeter of CMTMAX change decreased with age (r = -0.52 and -0.34, respectively, P < 0.05). The ciliary muscle forward movement correlated with the lens deformation (r = -0.35 and 0.40 for amplitude, while r = 0.36 and 0.58 for time constant, respectively, P < 0.05). CONCLUSIONS Age-related changes in the lens reshaping and ciliary muscle forward movement were found. Lens reshaping was much slower than the contraction of the ciliary muscle, especially in aging eyes, and this process required the ciliary muscle to contract more to reach a given response.

[1]  P. Kaufman,et al.  Age does not affect contractile responses of the isolated rhesus monkey ciliary muscle to muscarinic agonists. , 1993, Current eye research.

[2]  J. Rohen,et al.  Posterior attachment of ciliary muscle in young, accommodating old, presbyopic monkeys. , 1991, Investigative ophthalmology & visual science.

[3]  Ming Li,et al.  Anterior segment biometry during accommodation imaged with ultralong scan depth optical coherence tomography. , 2012, Ophthalmology.

[4]  P. Kaufman,et al.  Accommodation and presbyopia. , 2001, International ophthalmology clinics.

[5]  Adrian Glasser,et al.  Accommodation dynamics in aging rhesus monkeys. , 1998, American journal of physiology. Regulatory, integrative and comparative physiology.

[6]  J. Sivak,et al.  Age-Related Changes in Human Ciliary Muscle , 2000, Optometry and vision science : official publication of the American Academy of Optometry.

[7]  S. Strenk,et al.  Magnetic resonance imaging of the anteroposterior position and thickness of the aging, accommodating, phakic, and pseudophakic ciliary muscle , 2010, Journal of cataract and refractive surgery.

[8]  Leon N Davies,et al.  The effect of ageing on in vivo human ciliary muscle morphology and contractility. , 2011, Investigative ophthalmology & visual science.

[9]  Adrian Glasser,et al.  Quantification of age-related and per diopter accommodative changes of the lens and ciliary muscle in the emmetropic human eye. , 2013, Investigative ophthalmology & visual science.

[10]  R F Fisher,et al.  The force of contraction of the human ciliary muscle during accommodation , 1977, The Journal of physiology.

[11]  Kenneth J. Ciuffreda,et al.  Dynamic aspects of accommodation: age and presbyopia , 2004, Vision Research.

[12]  D. Atchison,et al.  MRI study of the changes in crystalline lens shape with accommodation and aging in humans. , 2011, Journal of vision.

[13]  Shanhui Fan,et al.  Optical coherence tomography for whole eye segment imaging. , 2012, Optics express.

[14]  Chiu-Yen Kao,et al.  Measuring Changes in Ciliary Muscle Thickness with Accommodation in Young Adults , 2012, Optometry and vision science : official publication of the American Academy of Optometry.

[15]  Alexander Duane,et al.  Are the Current Theories of Accommodation Correct , 1925 .

[16]  E F FINCHAM,et al.  The proportion of ciliary muscular force required for accommodation , 1955, The Journal of physiology.

[17]  Robert J. Lee,et al.  THE MECHANISM OF ACCOMMODATION. , 1895 .

[18]  Ronald A. Schachar,et al.  Age related changes in accommodative dynamics in humans , 2007, Vision Research.

[19]  Fan Lu,et al.  Repeated Measurements of the Anterior Segment During Accommodation Using Long Scan Depth Optical Coherence Tomography , 2012, Eye & contact lens.

[20]  P. Kaufman,et al.  Age-related loss of ciliary muscle mobility in the rhesus monkey. Role of the choroid. , 1992, Archives of ophthalmology.

[21]  P. Kaufman,et al.  Age-related changes in centripetal ciliary body movement relative to centripetal lens movement in monkeys. , 2009, Experimental eye research.

[22]  G. L. Van Der Heijde,et al.  In vivo determination of the biomechanical properties of the component elements of the accommodation mechanism , 1994, Vision Research.

[23]  P. Kaufman,et al.  Extralenticular and lenticular aspects of accommodation and presbyopia in human versus monkey eyes. , 2013, Investigative ophthalmology & visual science.

[24]  R. Schachar,et al.  Mechanism of Accommodation , 2001, International ophthalmology clinics.

[25]  Fabrice Manns,et al.  Imaging and full-length biometry of the eye during accommodation using spectral domain OCT with an optical switch , 2012, Biomedical optics express.

[26]  Jane F. Koretz,et al.  The mechanism of presbyopia , 2005, Progress in Retinal and Eye Research.

[27]  P. Kaufman,et al.  Accommodative ciliary body and lens function in rhesus monkeys, I: normal lens, zonule and ciliary process configuration in the iridectomized eye. , 2006, Investigative ophthalmology & visual science.

[28]  Yilei Shao,et al.  Versatile optical coherence tomography for imaging the human eye , 2013, Biomedical optics express.

[29]  L Stark.  Presbyopia in light of accommodation. , 1988, American journal of optometry and physiological optics.

[30]  G L van der Heijde,et al.  Age-Related Changes in the Accommodation Mechanism , 1996, Optometry and vision science : official publication of the American Academy of Optometry.

[31]  J L Semmlow,et al.  Age-related changes in human ciliary muscle and lens: a magnetic resonance imaging study. , 1999, Investigative ophthalmology & visual science.

[32]  Ming Li,et al.  Extended scan depth optical coherence tomography for evaluating ocular surface shape. , 2011, Journal of Biomedical Optics.

[33]  Harry J. Wyatt,et al.  Application of a simple mechanical model of accommodation to the aging eye , 1993, Vision Research.

[34]  Johannes W. Rohen,et al.  Age-related changes of the human ciliary muscle. A quantitative morphometric study , 1992, Mechanisms of Ageing and Development.

[35]  Haotian Lin,et al.  Anterior segment variations with age and accommodation demonstrated by slit-lamp-adapted optical coherence tomography. , 2010, Ophthalmology (Rochester, Minn.).

[36]  Yilei Shao,et al.  Simultaneous real-time imaging of the ocular anterior segment including the ciliary muscle during accommodation , 2013, Biomedical optics express.

[37]  Nhung X Nguyen,et al.  Measurement of accommodation after implantation of an accommodating posterior chamber intraocular lens , 2003, Journal of cataract and refractive surgery.

[38]  J S Wolffsohn,et al.  Subjective and objective performance of the Lenstec KH-3500 “accommodative” intraocular lens , 2006, British Journal of Ophthalmology.

[39]  Iwona Gorczynska,et al.  Anterior segment imaging with Spectral OCT system using a high-speed CMOS camera. , 2009, Optics express.