Changes in the static accommodation response with age

Kalsi, M.; Heron, Gordon; Charman, W. N.

doi:10.1046/j.1475-1313.2001.00546.x

Cited by 37 publications

(72 citation statements)

References 47 publications

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“…As the eye ages, accommodative ability declines, but in early presbyopia residual accommodation remains crucial for achieving functional near vision, often supplemented by low add power corrections . However, few studies have examined accommodative behaviour in this age group, and typically these studies have employed an impoverished stimulus set . Even with the full suite of accommodative stimuli, the present results emphasise a rapid change in accommodative ability between ages 42 and 50 ( Figure ), with an accompanying decline in image quality when viewing near stimuli ( Figure ) emphasising that previously reported low accommodative gains in early presbyopes were not due an incomplete suite of accommodative stimuli.…”

Section: Discussionsupporting

confidence: 51%

“…We systematically examined the effect of age on key measures of the near response in Figure . Because the typical accommodative responses of early presbyopes showed saturation with nearer targets (see Figures ), we fit the accommodative response functions with a regression line over the range where they were able to track the stimulus . Accommodative amplitude showed an obvious decline starting at age 40 reaching zero as age approaches 50 years ( Figure a ).…”

Section: Resultsmentioning

confidence: 99%

“…Most studies of declining accommodation in ageing subjects employed impoverished stimuli, e.g. monocular viewing conditions, which removed binocular convergence cues, or a monocular Badal optometer, which removed proximal and convergence cues …”

Section: Introductionmentioning

confidence: 99%

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Accommodation and pupil behaviour of binocularly viewing early presbyopes

Almutairi

Altoaimi

Bradley

2017

Ophthalmic Physiologic Optic

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Purpose: To study accommodation behaviour of early presbyopes with the full suite of accommodative stimuli, and to monitor changes in spherical aberration, pupil size and image quality that accompany the accommodative response. Methods: Using a high resolution Shack-Hartmann aberrometer, we measured refractive state as a binocularly viewed 0.30 logMAR (6/12 or 20/40) letter E was moved from 2 m to 20 cm and simultaneously monitored pupil diameter and spherical aberration for 19 subjects (mean age: 42 AE 7.18 years). Refractive state was defined using three standard criteria: minRMS, paraxial, and optimum image quality using the Visual Strehl ratio metric (VSOTF). Results: Because of changes in spherical aberration, accommodative gain measured with the paraxial criterion is generally greater (on average by 34%) than the minRMS gain in early presbyopes. The slope of stimulus/response curve is relatively stable up to age 41 and then declines progressively in spite of a full binocular set of accommodative cues. Reduced accommodative gain appears once accommodative amplitude has dropped to below 3D, and gain drops to <0.5 as amplitude drops to 1.5D. This decline happens at different ages in different presbyopes. Conclusion: Prior to the early 40s, changes in accommodation are restricted to a reduction in amplitude, but during the 40s the continued loss of accommodative amplitude is accompanied by a concurrent drop in accommodative gain. Therefore, reduced near image quality in early presbyopes is caused by lower accommodative amplitudes and gains, which may explain the apparent acceleration in symptoms and near add prescriptions during the mid to late 40s.

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Section: Discussionsupporting

confidence: 51%

Section: Resultsmentioning

confidence: 99%

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Accommodation and pupil behaviour of binocularly viewing early presbyopes

Almutairi

Altoaimi

Bradley

2017

Ophthalmic Physiologic Optic

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“…Accommodation range can drop below 4 diopters in some individuals as early as 35 years old [18]. Although we did not measure the maximal depth of focus for each subject nor visual acuity at near, we can safely assume that the older (average age 45 years old) subjects had smaller amplitudes of accommodation than the younger (average age 25 years old) ones [19,20]. Thus, we suggest that the range of accommodation in the young subjects was sufficient to allow easy and steady fixation at 50 and 25 cm, making the pattern stimulus located 200 cm away to appear blurred.…”

Section: Discussionmentioning

confidence: 99%

Effect of defocusing and of distracted attention upon recordings of the visual evoked potential

et al. 2004

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Pattern reversal visual stimuli are used to evoke potentials (VEPs) for assessment of visual acuity and for localizing defects along the visual pathways. Our goal was to assess the importance of attention and defocusing to the recordings of pattern VEP. Forty-one volunteers with normal (6/6) corrected visual acuity participated in this study. Twenty-one were asked to defocus intentionally the visual stimulus (located 200 cm away) by fixating at a target 25 or 50 cm from the eye. Twenty other subjects performed auditory tasks to distract their attention from the visual stimulus. Pattern VEPs were elicited by different check sizes. The amplitude and time-to-peak of the P100 wave were measured. Intentional defocusing caused amplitude reduction and prolongation of the time-to-peak in young subjects (20-34 years old). With the smallest checks used (7.5') we could not record a reliable response from 43% of the young subjects (6 out of 14). In older patients (35-61 years old), intentional defocusing induced negligible effects on pattern VEPs regardless of check size. There were no effects of auditory distraction upon the pattern VEPs. Our data suggest that intentional defocusing can produce false positive results (reduced VEP with prolonged time-to-peak) only when small checks are used in young subjects. Divided attention has negligible effect on the recordings of pattern VEPs. With proper controls, the pattern VEP test can be used for objective assessment of visual function.

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“…Previous studies have reported that the disparity-vergence system is not influenced by age 68–70 , although decreases in disparity-vergence peak velocity with age has been reported 71 . Subject-dependent variations in the ability to adapt vergence responses has also been shown in previous studies 33, 49, 72, 73 .…”

Section: Discussionmentioning

confidence: 84%

Adaptation to Progressive Additive Lenses: Potential Factors to Consider

Alvarez

Kim

Granger-Donetti

2017

Sci Rep

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People develop presbyopia as part of the normal aging process. Most presbyopes adapt to progressive additive lens (PALs), while others do not. This investigation sought to determine whether the ability to modify disparity vergence or phoria was correlated to PALs adaptation. In experiment 1, a double-step paradigm quantified the ability to modify convergence responses in sixteen presbyopes. In experiment 2, thirty-one incipient presbyopes participated in a 5-minute sustained fixation task to evoke phoria adaptation where the magnitude and rate of phoria adaptation were measured. Then, the experiment was repeated after wearing PALs for one month. Linear regression analyses were conducted between the following parameters: near point of convergence, positive fusional vergence at near, vergence facility, net change in the magnitude of phoria adaptation, and the rate of phoria adaptation. The ability to change convergence average peak velocity was significantly greater (p < 0.03) in presbyopic PALs adapters compared to presbyopic PALs non-adapters. The rate of phoria adaptation and vergence facility were significantly greater (p < 0.03) in incipient presbyopic PALs adapters compared to incipient presbyopic PALs non-adapters. Vergence facility and the rate of phoria adaptation may have potential clinical utility in differentiating which patients may adapt to PALs and which ones will have more difficulty.

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Changes in the static accommodation response with age

Cited by 37 publications

References 47 publications

Accommodation and pupil behaviour of binocularly viewing early presbyopes

Accommodation and pupil behaviour of binocularly viewing early presbyopes

Effect of defocusing and of distracted attention upon recordings of the visual evoked potential

Adaptation to Progressive Additive Lenses: Potential Factors to Consider

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