摘要:

Examination of the relationship between the sagittal depth of the cornea and the sagittal depth of an optimally fitting soft contact lens reveals that base curves are not always well chosen. The author reports a new system for selecting the number, range, and distribution of base curve radii such that the range of saggital depths clinically encountered is covered evenly. The saggital increment between adjacent base curves is then 0.1 mm.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Thick and thin hydrophilic lenses with otherwise similar parameters were worn by patients for a period of 6 months. The thicker lenses produced greater changes in corneal sensitivity and thickness during the course of adaptation and wear than did the thinner lenses. Chronic edema levels of 3–4% were noted with the thick lenses. Changes in corneal power for each lens group were not significant. Thin hydrophilic lenses seemed to produce less upset of normal corneal physiology over the course of the 6-month wearing period.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Monocular visual acuities in a binocular field of view, field of view under binocular conditions, and retinal correspondence were investigated in five intermittent exotropes of the divergence excess type. Results indicated that all five intermittent exotropes demonstrated (1) normal visual acuity in the deviating eye without suppressing the fixating eye, (2) a lateral extension of the temporal field of view (panoramic viewing), (3) anomalous retinal correspondence.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Measurements of oxygen transmissibility are reported for hydrogel lenses of different power. Center thickness is related to oxygen transmissibility, and it is shown that the relation is different for lenses of high dioptric power compared with lenses of low power. For high plus lenses, the oxygen transmissibility is higher than would be expected from a simple consideration of center thickness and the oxygen permeability of the contact lens material. For high minus lenses, the oxygen transmissibility is less than would be expected. Clinically, this means that power as well as center thickness must be taken into account when estimating the oxygen transmissibility of high power lenses.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

The characteristics, clinical appearance, and frequency of the rare corneal condition, keratoconus posticus Circumscriptus, are discussed. A bilateral case of this condition, examined by use of techniques not previously employed, is described.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

The presence of epicapsular stars (congenital epicapsular pigmentation) is a common occurrence, but it can become clinically significant when vision is impaired. A case history reporting such a condition is presented.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Full-field reversed 1.3x telescopes were used in the treatment of a 63-year-old male retinitis pigmentosa (R.P.) patient with a 5° central field. The patient was highly motivated to “expand” his visual field. He was trained intensively with 1.3x, 1.7x, and 2.2x reversed telescopes prior to prescribing. Evaluations by the Orientation and Mobility staff indicated significant improvements in his functioning with the devices. The reversed telescopes expanded his field to approximately 14°. Patient has been reevaluated after using the aid at home and remains enthusiastic about his successful use of the aid. This case is notable in that binocular, low-power, full-field, reversed telescopes are being used successfully for mobility, eating, and other tasks.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Tests of binocular functions were performed on a group of 147 patients with unilaterally or bilaterally implanted intraocular lenses. The quality of the binocular vision achieved was significantly better than that of unilateral aphakic patients wearing contact lenses. Compared to the normal population, the stereoscopic threshold in the pseudophakic population was found to be slightly poorer. Visual acuity, anisometropia, lens fixation, and vertical deviation were analyzed in relation to stereopsis.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Over-refraction provides a powerful method for the refractive examination of the aphakic or highly ametropic patient. Nevertheless, in the past, practical difficulties that attend mathematical or graphical combination of over-refraction and original spherocylinders have tended to limit the clinical use of over-refraction methods. Programmable calculators, now available inexpensively, render over-refraction clinically practical. An over-refraction program for the Texas Instruments TI-59 Card-Programmable Calculator is presented. Program running time, exclusive of data entry and readout, is under 15 sec.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Translator's Note: Some of the information contained in this translation was included in an oral presentation by Prof. Avetisov at a symposium held in Giessen in 1966, and was published in English as a paper (Methods and Results in Examination of Fixation in Amblyopia) inInternational Strabismus Symposium, editor, A. Arruga, Basel/Switzerland, S. Karger, pp. 14–19, 1968. Several authors1–4have cited this short symposium paper with differing interpretations. Correspondence with Avetisov for clarification revealed that a more complete version of his study was published as a chapter in Russian, which is translated here with the author's permission. Avetisov's results are tied to the important and current question of whether acuity is higher at the fovea or at the eccentric locus of eccentrically fixating amblyopic eyes; the answer bears directly on the etiology of eccentric fixation.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID