摘要:

Corneal curvature was measured in 10 kittens from three litters and found to change significantly during postnatal development. From our data analysis, corneal curvature can be predicted from an animal's age and weight. To facilitate this prediction for use in fitting contact lenses as occluders or diffusers in developmental studies, prediction equations are given as are expected weights of kittens as a function of age.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

The axial chromatic aberration of the eye was determined as in previous studies by finding the lens required to eliminate or minimize blur of the fixation target when it is illuminated by a series of monochromatic sources. Objective measurement of the refraction of the eyes during this procedure showed that accommodation remained constant throughout. Hence, the conclusion that the accommodative state does not in this case respond automatically to changes in the vergence of light falling in the retinal plane. It is suggested that some other stimulus, perhaps perceived distance, predominates. Further, the least amount of plus lens required to blur a near target was about the same for white and red but much less for blue. This substantiates an earlier finding that the eye accommodates for near only sufficiently to place the blue end of the chromatic interval on the retina.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Thirty-three patients (63 eyes) were fitted with Bausch and Lomb SoftensR(polymacon) contact lenses. The initial lenses were selected with the mean posterior apical radius 0.45 mm flatter than the flat keratometer reading of the cornea (S.D. = ±0.31 mm). Forty-eight eyes (76%) were successfully fitted and 15 eyes (25%) were unsuccessfully fitted. Among the successfully fitted eyes, 31 were fitted with the initial lens, 12 required steeper lenses, and 5 required flatter lenses. The final successfully fitted lenses were on the average 0.40 mm flatter (S.D. = ±0.32 mm) than the flat keratometer reading of the cornea. The unsuccessfully fitted lenses were not significantly different than the successfully fitted lenses, being 0.47 mm flatter (S.D. = ±0.32 mm) than the flat keratometer reading of the cornea. Although the central lens-cornea relationship is helpful in fitting the Soflens, the number of successful results are increased significantly by changing to a lens with different parameters when lens performance and patient response are not optimal.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

At threshold the eye is known to sum quanta as though the total catch were important and not the distribution on the retina. In humans, spatial summation is larger under dark adapted conditions. The extent of this spatial summation is studied in goldfish retinal ganglion cells which are known to receive both rod and cone inputs. The area of summation in single ganglion cells is found to be much larger for rod input compared to cone input. It seems that in single ganglion cells, the spatial summating properties increase markedly in the dark due largely to the neural organization of rod and cone input.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

The distance and near lateral heterophorias were investigated in 10 subjects to determine the effect of a nitrous oxide (N2O)-oxygen (O2) mixture. The heterophorias were measured by the Maddox method before and after a 3-minute induction period of nitrous oxide. It was found that the distance lateral heterophoria for all 10 subjects changed toward more esophoria, whereas the changes in the near lateral heterophoria were inconsistent in their direction.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

A review of the biofeedback literature was made and proposals for use in optometry advanced. To this end electromyograph units can be connected to an apparatus which gives a reward when a patient performs proper eye movements. By this means, patients who undergo visual training become conscious of their eye movements. As a reinforcement, they are rewarded by music or the motion of toys when they give the right answer. Application of the system in cases of strabismus, limitation of gaze, convergence insufficiency or excess, ptosis, and other cases are discussed. Methodological and financial advantages of incorporation of biofeedback reinforcement into visual training are enumerated.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

A series of 35-mm vectographic checkerboard slides has been developed which, when projected through a rotating polaroid analyzer, generate an oscillating checkerboard for use as a stimulus in visual evoked response (VER) experiments. Sample VER data are presented from a 4-year-old and a 23-year-old subject, using a variety of check sizes and using a color-sound cartoon superimposed over the checkerboard to encourage attention. These slides provide a simple yet versatile means for producing VER data.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Laser meridional refractions were undertaken on 30 subjects. The results were compared to classical subjective techniques utilizing both correlative statistics and clinical criteria. The laser meridional techniques were highly correlated with the subjective procedures and were accurate when judged by clinical criteria.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

A vertical diplopia in a 53-year-old woman was diagnosed as euthyroid Grave's disease, which was arrested by systemic chemotherapy. Subsequent corrective surgery was effective.

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1976

数据来源: OVID