14-18) While there is conjecture as to whether accommodative inaccuracy is a feature rather than a cause of myopia, (19) children with insufficient accommodation exhibited as either lag or lower baseline accommodative amplitude
have shown greater myopia control results with progressive addition lenses and orthokeratology than myopes with normal accommodative function.
These subjective and objective test results were compared to characterize changes in accommodative amplitude "from preschool to presbyopia.
For the oldest age group, 51 to 63 years, accommodative amplitude was essentially zero.
Minus-lens-stimulated accommodative amplitude
decreases sigmoidally with age: a study of objectively measured accommodative amplitudes
from age 3.
Accommodative responses, including both monocular and binocular accommodative amplitude
, accommodative convergence to accommodation ratio, and negative and positive relative accommodation, were reduced in the TBI population compared with normative values.
In particular, the paper states longitudinal studies that consider the interaction between the preferred reading distance and the change in accommodative amplitude
across time for males and females could help determine to what extent biological factors or environmental factors plays a role in the loss of focusing ability with increasing age.
The potential accommodative amplitude
of passive-shift IOLs is dependent upon the power of the implant (and therefore the patient's refractive error).
Many of the earlier studies employed accommodative amplitude
as the primary or sole index of accommodative dysfunction.
It has a myriad of unique capabilities, including the wavefront analysis of normal eyes; wavefront analysis of eyes with irregular corneas due to disease or refractive surgery complications; highly reproducible automated refractive error assessment; non-orthogonal astigmatic axis determination; contrast sensitivity assessment; ablation profile mapping; accommodative amplitude
quantification; and its overall capability to perform total visual function analysis.
Measurement of accommodative amplitude
38 In the same patients, however, the study showed that cyclopentolate was more effective than tropicamide in reducing accommodative amplitude
in adult myopes (near-point testing).
Accommodation can be measured in several different ways, but at least an assessment of accommodative amplitude
should be included in any child's eye examination.