Results 221 to 230 of about 12,483 (262)

Ocular accommodation in chickens: Corneal vs lenticular accommodation and effect of age

Vision Research, 1986
The avian accommodative response has long been suspected of having a corneal component resulting from contraction of a limbal extension of the ciliary muscle. Efforts to confirm the existence of such a mechanism have been sporadic and the results contradictory.
J G, Sivak, T E, Hildebrand, C G, Lebert, L M, Myshak, L A, Ryall   +4 more
openaire   +2 more sources

Role of ocular aberrations in dynamic accommodation control

Clinical and Experimental Optometry, 2009
Accommodation control is mediated by a number of cues, including blur,chromatic aberration and target proximity. Data from wavefront measurements have shown clear shifts in ocular aberrations during increasing accommodative demand, most notably a negative shift in spherical aberration. Work in adaptive optics, where aberrations have been corrected, has
Chin, Sem Sem, Hampson, Karen; id_orcid 0000-0001-9146-9135, Mallen, Edward A.H.   +2 more
openaire   +2 more sources

Modification of pattern reversal VERs by ocular accommodation

Vision Research, 1985
The amplitudes and implicit times of the P-1 component of monocular transient pattern VERs elicited by reversing checkerboard targets were measured in 6 conditions: (1) Ocular accommodation (Ao) elicited by minus power ophthalmic lenses; (2) Ao stimulated by minus lenses with the natural pupil of the test eye dilated and replaced by an artificial pupil;
J V, Lovasik, M, Spafford, M, Szymkiw
openaire   +2 more sources

Comparison of changes in ocular aberrations with accommodation and accommodative facility

Acta Ophthalmologica
Aims/Purpose: This study aimed to analyse whether a relationship exists between subjectively measured monocular Accommodative Facility (AF), the magnitude of the revolution‐symmetric Zernike coefficients C20, C40 and C60, and the objectively measured Accommodative Response (AR).Methods: A total of 66 eyes, from 33 healthy young volunteers (26 women and
Maria Mechó García, María Arcas Carbonell, Elvira Orduna Hospital, Ana Sánchez Cano   +3 more
openaire   +1 more source

Accommodative and Vergence Findings in Ocular Myasthenia

Journal of Neuro-ophthalmology, 2000
Myasthenia gravis (MG) is a neuromuscular disorder that affects skeletal muscles, in particular, the extraocular muscles. Response variability is a hallmark sign. Detailed findings are described in a patient with MG in which the presenting sign was accommodative insufficiency.
J, Cooper, G J, Pollak, K J, Ciuffreda, P, Kruger, J, Feldman   +4 more
openaire   +2 more sources

Volume change of the ocular lens during accommodation

American Journal of Physiology-Cell Physiology, 2007
During accommodation, mammalian lenses change shape from a rounder configuration (near focusing) to a flatter one (distance focusing). Thus the lens must have the capacity to change its volume, capsular surface area, or both. Because lens topology is similar to a torus, we developed an approach that allows volume determination from the lens cross ...
R, Gerometta, A C, Zamudio, D P, Escobar, O A, Candia   +3 more
openaire   +2 more sources

Autonomic correlates of ocular accommodation and cardiovascular function

Ophthalmic and Physiological Optics, 2009
Abstract Purpose:  To evaluate the hypothesis that objective measures of open‐ and closed‐loop ocular accommodation are related to systemic cardiovascular function, and ipso facto autonomic nervous system activity.
Leon N, Davies, James S, Wolffsohn, Bernard, Gilmartin   +2 more
openaire   +2 more sources

A Biometric Study of Ocular Changes During Accommodation

American Journal of Ophthalmology, 1993
We performed a biometric study that used A-mode ultrasonography on 106 subjects during ocular accommodation. The subjects were divided into two groups; group 1 included 76 subjects and group 2 included 30 subjects. In group 1, we measured the anterior chamber depth, lens thickness, and axial length in the right eye while the left eye, wearing ...
P J, Shum, L S, Ko, C L, Ng, S L, Lin
openaire   +2 more sources

Accommodative Esotropia After Ocular and Head Injury

American Journal of Ophthalmology, 1990
Five children lost their ability for motor fusion after traumatic injury to either the eye or head. All patients had the onset of accommodative esotropia within two months of the traumatic episode. The ocular alignment of each child was controlled by the use of spectacles that corrected the accommodative requirements.
openaire   +2 more sources

Cyclodextrin-based ocular drug delivery systems: A comprehensive review

Coordination Chemistry Reviews, 2023
Guihua Fang, Qiuxiang Wang
exaly