摘要:

The optical theory of keratophakia employing implant lenticules with a refractive index different from that of the cornea is presented. This generalized theory also embraces keratophakia employing donated stromal lenticules and keratomileusis, with equal accuracy. The method of solution of the formulas is indicated. The effects of the various parameters upon the radius of curvature to be applied to the cornea are illustrated and discussed.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Three subjective determinations of the reading addition required by each of 10 subjects were obtained in this study with the use of a cross cylinder grid target, a variable color, near-point, grid target and an ordinary reading card. All three methods gave similar results. In addition, there was no change in the measurement when the color of the horizontal and vertical lines was reversed on the variable color, near-point, grid target.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

The prevalence of divergence excess was assessed from the records of 250 consecutive patients attending a binocular-vision clinic. The 67 cases in the sample showing divergence excess were subdivived into the following groups: (1) secondary to operations for esotropia (8 cases); (2) anisometropic amblyopes (14 cases); (3) basic (14 cases); (4) convergence weakness (13 cases); (5) divergence excess (18 cases). Treatment methods placed heavy emphasis on physiological diplopia. Of the 18 in the divergence excess category, 14 began treatment, 10 showed a satisfactory outcome, two achieved some improvement, and two discontinued treatment on their own. Divergence excess seems to respond well to nonsurgical treatment.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

A schema is proposed for management of optometrical patients who may have glaucoma or any of 22 risk factors of glaucoma. The assessment system has established decision points and management pathways based on risk factors in glaucoma which employ only clinical procedures appropriate to current optometrical practice. This schema is particularly designed to permit diagnosis of early angle-closure glaucoma while the disease is in the symptomless phase, prior to chronic elevation of intraocular pressure and the development of damage to the optic disc and visual fields.A recommendation is made for inclusion of the Van Herick test as routine and in the assessment of patients entering the schema. Gonioscopy should form part of the diagnostic workup, but an alternative pathway is established for use when this technique is omitted.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

The prevalence of the corneal Hudson-Stähli line among 400 eyes was found to range from 5.3% of the eyes of patients aged 11–20 years to 100% of eyes of patients aged 81–90 years. In 87.3% of patients over 50 years of age corneas were affected; this percentage is considerably higher than previous estimates. Up to the age of 60 years it occurs more frequently in men than in women.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

This paper presents a digest of 50 retinal research projects reported in one British and two American journals from July 1976 through June 1977. The articles reviewed report recent developments pertaining to effects of excessive light on retinal tissue in newborn rats, pathogenesis of cotton-wool spots, control of the blood-retinal barrier in diabetes, infections, macular diseases, variations in retinal pigment epithelium, and retinal detachment.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Central gyrate atrophy is a rare ocular finding with a unique pathogenesis and fundus appearance. This entity results in total atrophy of the large and small vessels of the choroid and concomitant changes in the outer layers of the retina. A case report is presented to demonstrate the clinical appearance of this lesion and its relationship to the pathogenesis.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

An optometer (infrared recording retinoscope) that provides high resolution measurements of accommodative changes of the eye has been developed. The instrument employs the principle of retinoscopy to monitor changes in the refractive state of the eye. Infrared radiation is scanned across the eye to provide a moving retinal source as in retinoscopy. An electro-optical system replaces the observer in determining the direction and amount of apparent motion in the pupil of the patient. The optometer is sensitive to accommodative changes of 0.12 D over a range of 12 D. The response of the instrument is faster than the most rapid changes of accommodation, and measurements are unaffected by pupil changes or by small eye movements.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

Precision of measurement of apparent corneal thickness with the Haag-Streit lamp depth measuring attachment is significantly enhanced by staining the precorneal film with sodium fluorescein before measuring.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID

摘要:

High-quality slit lamp photographs require a balance between slit beam exposure and exposure of surrounding ocular structures. Proper exposure of surrounding ocular structure is difficult to obtain with the Nikon photo-slit lamp. The purpose of this research was to design an accessory fill-in flash for this slit lamp, which would provide proper exposure of overall ocular structures. In addition, this paper describes the procedures used to obtain proper exposure values and provides an exposure table for this accessory flash unit.

ISSN:0093-7002    

出版商:OVID    

年代:1979

数据来源: OVID