amplitude of accommodation

(redirected from Accommodative amplitude)
Also found in: Encyclopedia.


adjustment, especially adjustment of the eye for seeing objects at various distances. This is accomplished by the ciliary muscle, which controls the lens of the eye, allowing it to flatten or thicken as is needed for distant or near vision.
Flattening and rounding of lens during accommodation.
absolute accommodation the accommodation of either eye separately.
amplitude of accommodation range of accommodation.
histologic accommodation changes in morphology and function of cells following changed conditions.
negative accommodation adjustment of the eye for long distances by relaxation of the ciliary muscle.
positive accommodation adjustment of the eye for short distances by contraction of the ciliary muscle.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

am·pli·tude of ac·com·mo·da·tion

the difference in refractivity of the eye at rest and when fully accommodated.
Farlex Partner Medical Dictionary © Farlex 2012

am·pli·tude of ac·com·mo·da·tion

(am'pli-tūd ă-kom'ŏ-dā'shŭn)
The difference in refractivity of the eye at rest and when fully accommodated.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Recently, there is a well-designed randomized clinical trial with placebo therapy group [25] investigating effectiveness of vision therapy for accommodation in children with accommodative dysfunction which were defined as having decreased accommodative amplitude with respect to age, accommodative facility, or both and it showed significant improvement in amplitude and facility.
The baseline testing included Convergence Insufficiency Symptom Survey (CISS) questionnaire [32], visual acuity, cover test at distance and near, accommodative amplitude and facility, Monocular Estimation Method (MEM) retinoscopy [33], objective assessment of lag of accommodation, near point of convergence, step vergence, vergence facility, and a cycloplegic refraction using 1% Tropicamide.
This testing was conducted at the discretion of the attending optometrist and may have included additional accommodative testing (positive/negative relative accommodation, fused cross cylinder, accommodative amplitudes, accommodative facility) and vergence testing (distance and near lateral and vertical phorias, distance and near convergence and divergence ranges, vertical vergence ranges).
Five of the patients exhibited accommodative dysfunctions, with all five manifesting reduced accommodative amplitude and two exhibiting slowed accommodative facility [21].
Minus-lens accommodative amplitude, PRA, and NRA were all determined in the phoropter using the line of 20/30 letters on a reduced Snellen chart [27].
Dual optic AIOL designs have been developed to overcome the dependence of potential accommodative amplitude on refractive error (and optic power), which limits single optic AIOLs.
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.
Phoropters are also used to measure heterophorias, accommodative amplitudes and accommodative lags/logs/posture, horizontal & vertical vergences and more.