Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 739353

Antipodean squint.

S Shippman·J S Hermann
View original source ↗Export metadata ↓

Abstract

Strabismic cases which are exotropic fixing with one eye, and esotropic fixing with the other eye are rare and a result of anisometropia, unequal accommodation, paresis or restriction, and previous ocular muscle surgery. Three cases of antipodean squint are reported without known etiology factor. An extensive survey of experts in the field of strabismus was unable to document other similar cases where a cause could not be determined.

Explore related subjects

Accommodation, OcularChild, PreschoolFemaleHumansInfantMaleOculomotor MusclesOphthalmoplegiaRefractive ErrorsSaccadesStrabismusSurgical Procedures, OperativeTonometry, OcularVision TestsCase ReportsJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

S Shippman, J S Hermann. Antipodean squint.. https://doi.org/10.3928/0191-3913-19780701-05

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2006

Depth-of-focus: control system implications.

The depth-of-focus (DOF) plays a major role in accommodative control. It provides a neurological tolerance for retinal defocus and the perception of blur. Hence, the DOF has been an important component in bioengineering models of the accommodative system, but with its model-based control function limited to the fovea. However, new studies have demonstrated the influence of the near retinal periphery on the DOF: with increased target extent, the DOF increases. Thus, the blur control derived from the combined fovea and near retinal periphery should be incorporated into future models of accommodation.

Accommodation, Ocular↗
PubMed2006

Contrast sensitivity function and ocular higher-order wavefront aberrations in normal human eyes.

PURPOSE: To investigate the relation between contrast sensitivity function and ocular higher-order wavefront aberrations in normal human eyes. STUDY DESIGN: Prospective observational case series. PARTICIPANTS: Three hundred seven eyes of 161 normal subjects, ranging in age from 15 to 60 years (30.9+/-8.0 [mean +/- standard deviation]). METHODS: Ocular higher-order aberrations were measured for a 4-mm pupil using the Hartmann-Shack wavefront analyzer. The root-mean-square of the third- and fourth-order Zernike coefficients was used to represent comalike and spherical-like aberrations, respectively. We measured contrast sensitivity, low-contrast visual acuity (VA), and letter contrast sensitivity. From the contrast sensitivity data, the area under the log contrast sensitivity function (AULCSF) was calculated. Pupil diameter in a photopic condition was recorded using a digital camera. RESULTS: Multiple linear regression analysis revealed that comalike aberration (P = 0.002) was significantly associated with AULCSF, but spherical-like aberration (P = 0.200), age (P = 0.185), and photopic pupil diameter (P=0.252) were not. Comalike aberration showed a significant correlation with low-contrast VA (P<0.001), but spherical-like aberration (P = 0.293), age (P = 0.266), and pupil diameter (P = 0.756) did not. Comalike aberration was found to be significantly associated with letter contrast sensitivity (P<0.001), but spherical-like aberration (P=0.082), age (P = 0.370), and pupil diameter (P = 0.160) were not. CONCLUSIONS: In normal human eyes, comalike aberration of the eye significantly influences contrast sensitivity function.

Accommodation, Ocular↗
PubMed2006

Insights into the age-related decline in the amplitude of accommodation of the human lens using a non-linear finite-element model.

AIM: To understand the effect of the geometric and material properties of the lens on the age-related decline in accommodative amplitude. METHODS: Using a non-linear finite-element model, a parametric assessment was carried out to determine the effect of stiffness of the cortex, nucleus, capsule and zonules, and that of thickness of the capsule and lens, on the change in central optical power (COP) associated with zonular traction. Convergence was required for all solutions. RESULTS: Increasing either capsular stiffness or capsular thickness was associated with an increase in the change in COP for any specific amount of zonular traction. Weakening the attachment between the capsule and its underlying cortex increased the magnitude of the change in COP. When the hardness of the total lens stroma, cortex or nucleus was increased, there was a reduction in the amount of change in COP associated with a fixed amount of zonular traction. CONCLUSIONS: Increasing lens hardness reduces accommodative amplitude; however, as hardness of the lens does not occur until after the fourth decade of life, the age-related decline in accommodative amplitude must be due to another mechanism. One explanation is a progressive decline in the magnitude of the maximum force exerted by the zonules with ageing.

Accommodation, Ocular↗