摘要:

It is frequently stated that amblyopia is not correctable after the age of 6 years. Many practitioners report marked success for older patients. To evaluate these conflicting reports, we analyzed the results from 23 published amblyopia studies. Our analysis indicates that substantial numbers of patients over age 6 were successfully treated. Success rates under age 6 were not significantly better than those in older patients when the criterion for success was achievement of 20/30 acuity or better. When a criterion of 4 lines improvement was used, success rates at all ages under 16 were quite similar; in patients 16 and over, success by this criterion was significantly less frequent, but even in this group success was achieved by 42% of the patients.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Pupil responses to phenylephrine alone and to phenylephrine preceded by a topical anesthetic were recorded by means of an infrared pupillometer. In response to phenylephrine, pupils dilated more in eyes with pale irides. Dilation was greater if a topical anesthetic was applied before the mydriatic. Benoxinate, proparacaine, and tetracaine produced approximately equal degrees of enhancement of the mydriasis. One drop of 1% phenylephrine had only a small dilating effect on an eye when the fellow eye received the phenylephrine preceded by 0.5% proparacaine.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

A procedure is outlined for generating and displaying information about distortion in an ophthalmic lens. It involves a direct comparison of an object and its image as viewed at the entrance pupil of the eye. The same procedure may also be used to assess chromatic dispersion produced by the chromatic differences in magnification.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

The dimensions of soft contact lenses cannot be measured by methods used for hard lenses, so new techniques have had to be devised. This paper introduces standards and tolerances for the measurement of soft contact lenses. Previous methods of measuring these lenses are reviewed, and 2 new methods are described for measuring thickness and diameter. Instrument errors and the reliability of these methods are assessed.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Recently, small-screen measurements have suggested different types of visual loss in strabismic amblyopia. The present experiment examined the influence of field size on this conclusion for low- and high-frequency measurements. The original findings are believed to be independent of the grating field size, because (1) in the present study of 4 amblyopes, normal and amblyopic eyes were affected equally by increasing the number of cycles, and (2) the amblyopes' foveas did not have high-frequency discrimination superior to that of the eccentric area used for fixation.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

A contrast border, formed where 2 uniform fields of differing luminance meet, was viewed through filters containing a scattering agent. The filters resembled the cornea and crystalline lens in that the amount of light scattered increased exponentially toward the direction of the incident light. The perceptually enhanced regions on both sides of the border were measured for various concentrations of the scattering agent. Measurements were obtained for several luminances of the brighter field, the darker field remaining constant. It was found that the width of the enhanced region, both on the bright and on the dark side of the border, increased approximately linearly with the logarithm of the amount of light scattered. The increase was of approximately the same order for all of the luminances tested.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Reading speed and duration were measured for 24 low vision subjects, 12 learning to use closed circuit television and 12 learning to use optical aids. Reading speed and duration increased for both groups during 10 days of training and practice. Improvement occurred by steplike increases and plateaus. Visual acuity was not correlated with either performance measure; reading speed on the initial day of training was correlated with reading speed on the last day. The results have implications for both the prescription of aids and the training of low-vision patients.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Static retinoscopy can yield contaminated results because the central rays of the retinoscope beam are oblique with respect to the line of sight of the eye being examined. Additionally, it is difficult to obtain steady distant fixation by children and infants. A near-retinoscopy technique is described, and refractive errors obtained by subjective refraction and near retinoscopy on adults are compared to show that the latter technique yields reliable and valid measures of refraction.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

This report describes several methods of degrading imagery through the central portion of a spectacle lens to provide a cosmetically acceptable means of obtaining single vision in the central field of patients with intractable diplopia. For 2 strabismic patients with annoying diplopia, we applied to 1 spectacle lens a centrally placed disc (about 1 inch diameter) consisting of (1) translucent tap,a(2) a +7 D Fresnel lens,bor (3) stippled, clear lacquer. For 1 patient, the lacquer was the most acceptable; for the other, the tape was best. We present here the case reports for these 2 patients, showing why they preferred different image-degrading methods and how these and other methods of central-field image degrading can be advantageous even when diplopia is present across most of the visual field.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID