ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

Snellen acuity is determined as a functional of refractive error for two subjects under cyploplegia, using randomised test charts, constant test chart luminance and in serise of artificial pupils. These results allow determination of the depth-of-focus of the eye for Snellen targets, and it is shown that both optical and retinal factors influence the depth of-focus achieved. Depth-of-focus is found to increase with decreasing pupil diameter and visual acuity. The clinical significance of these results, particularly with respect to the precision with which refractive error may be determined, is discussed.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTThis study was designed to determine if spin-cast hydrogel contact lenses rotate on the eye, and if so investigate the parameters which influence rotation, if these leuses do rotate, correction of residual astigmatism may be difficult, if not impossible.We monitored the lens rotation associated with 12 specially marked B&L SoftensTMcontact lenses an six corneas. after insertion and 30 minutes later by use of high speed motion pictures to analyze lens rotation, the film was projected with a stop action projector and the amount of rotation measured with a protractor.Thirty-one percent of the 144 observations made showed some lens rotation, the majority of which was encyclorotation. Most of the leuses showed, little or no change in rotation between the two time periods.Cornell curvature was the only lens or eye parameter associated with ratation. Why lenses were more likely to rotate on steeper corneas is not fully understood.Our findings indicate that definite way rotate, but there is no definite way of determining in advance of a given lens will rotate on a given, eye. This emphasizes the need for individualized lens fitting and proper patient monitoring.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

Recent clinical evidence that dimnished corneal sensitivity occurs far more frequently (p < 0.003) among diabetics than nondibetics, supports the addition of aestbesometry to the routine optometric screening battery for patients at risk of diabetes. This evidence is reviewed and quantitative estimates are presented to illustrate the clinical efficacy of this screening test.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

We investigated the possibility of significant corneal trauma (as revaled by slit lamp observertion of the fluorescein instilled eye), and massage effects following determination of intraocular pressure with the A. O Non Contact tonometer (NCT). Fifteen different, normal human eyes were each aplamated 150 succesive times with the NCT. leading to the conclusion that only minor, superficial corneal epithelial defects sometimes resulted and that, in the line with other studies, the intially higher readins (about I mm), obtained with the NCT, were most likely due to patient apprebension, while the subsequently lower readings represented patient acceptance of the process and were not a result of true aqueous massage. As in an earlier study, we found the instrument variability to be about \pm 1 or \pm 2 mm and probably due to the subject's own cardiac cycle.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

Occular dominance, as measured in sighting tests involves a temporary suppression of the input from the non-dominant eye in order to avoid diplopia. Amblyopia ex anopsia may be viewed as a long term suppression of the input from one eye for the same reason. In the absence of amisometropia. paralysis of extra ocular muscles, or other factors which would tend to determine which eye would manifest suppression, the non-dominant sibing eye should be more likely to develop amblyopia given the presence of strabisms. A sample of 258 amblyopes supports this prediction based on the popultion norms for sigbing domainance.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

The stereapsis performance of 16 subjects was measured on an automated Howard Dolman apparatus and compared with their performance through a sample segment of a proposed B-1 aircraft windsbield Recognition visual acuity was determined for 15 subjects using a low-contrast Landolt C target viewed with and without the segment. When the task was performed through the windsbield segment, a statistically significant loss in stereopsis resulted, but no significant loss in visual acuity.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACT“Forced elimination” of anomalous correspondence in a patient with constant exotropia is discussed. Therapy was similar to classic visual therapy for esotropia: presenting targets at the augle of strabismus (Angle II) using a troposcope. Home theraphy methods using anaglyphic techniques and after-images are described.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTThe need for “in-depth” study of the status of binocularity in true space of both the non-strabismic and strabismic before orthoptics is discussed. Vectogram tests to ascertain the status of binocularity of the non-strabismic and the strabismic are explained. With the strabismic, the Single Oblique Mirror Stereoscope is used and the tests with it are enumerated. Significant embancement of diagnosis of the status of binocularity in the non-strabismic is obtained by testing over a prolonged period of time, instead of relying only upon tests based upon instantaneous response. Prolouged testing techniques utilizing Vectograms in which the patient uses alternating saccadic, jump, oculo-rotary fusional movements from the straight ahead position into the lower reading field are used.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID