摘要:

ABSTRACTTwo sets of multiple regression equations (prediction systems) were derived from the analysis of ocular biometric data obtained from glaucoma patients (16 open angle; 16 angle-closure) and 75 normal subjects. Discriminant scores were established for both sets of equations which minimised the number of false negatives. One set, the ‘Glaucoma Equations’ was applied to the data to segregate the glaucoma from the normal subjects. The other prediction system, the ‘Classification Equations’, was then applied to the group defined as glaucomatous to discriminate between patients in the angle-closure and open angle categories. The performance of these equations, obtained by comparing the predicted and actual classifications for this sample, was such that between 9 and 12% of false positives and 0 and 3% false negatives were found on the ‘Glaucoma Equations’ and between 6 and 12% of false positives with no false negatives on the ‘Classification Equations’.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTA method of glaucoma prediction from ocular biometric data has been described previously. A study was undertaken to evaluate the performance of the existing multiple regression equations (prediction systems) on data obtained from an independent sample consisting of 22 angle-closure glaucoma, 29 open angle glaucoma and 44 normal subjects. This performance, found by comparing the predicted and actual classification for this sample, was such that between 2 and 7% false positives and 12 and 27% false negatives were found on the equations differentiating glaucoma from normal subjects; and between 14 and 27% false positives, with 10 to 14% false negatives on the equations classifying the glaucoma subjects as angle-closure or open angle. From these results the efficiency of glaucoma prediction from ocular biometric data would appear to be equal to that of the combined tonography and provocative tests, provocation with corticosteroids and visual field screening.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTThe experiment was conducted on a sample of 26 subjects including both males and females and a control group of five. Their mean age was a little over 24 years. Corneal thickness and configuration were measured before and after the subjects had been wearing rigid and flexible contact lenses for three hours; measurements were also taken on control subjects at two different sessions, before and after a three-hour period. The statistical analysis showed a low but significant correlation between corneal thickness and corneal shape.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTSix males were administered a peripheral visual response time test to the onset of brief, small stimuli imaged in 10° arc separation intervals across the dark adapted horizontal retinal meridian under binocular and both monocular viewing conditions. This was done in an attempt to verify the existence of peripheral binocular summation using a response time measure. The results indicated that from 50° arc right to 50° arc left of the line of sight binocular summation is a reasonable explanation for the significantly faster binocular data. The stimulus position by viewing eye interaction was also significant. A discussion of these and other analyses is presented along with a review of related literature.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTContrast sensitivityafunctions (i.e. minimum contrast required to resolve a sine wave grating as a function of spatial frequency) were determined for subjects when wearing normal spectacle corrections and when wearing either hard or soft contact lenses. Comparison of results for spectacle correction and contact lens corrections provides a more definitive evaluation of visual performance with contact lenses than do the conventional clinical procedures.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTA recording retinoscope was developed to measure the luminance of the fundus reflex during problem-solving tasks. 10 students were used as subjects. The luminance of the reflex was recorded while the subjects read 5 passages of graded reading material and performed an addition task. A reversal design was used to determine the effects of pupil changes and accommodation on changes in the luminance of the reflex. Relatively large changes in the luminance of the reflex were recorded. These were due to accommodation. The subjects' comprehension of the reading material did not appear to affect the luminance of the reflex in the manner predicted by previous studies. However, a change in task from simple reading material to an addition task appeared to increase the luminance of the reflex.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTA technique is presented permitting control of input to each hemiretina and each hemisphere, of the various elements of a visual illusion. When the retinal effects and post-retinal effects are added, the result is greater than the total illusory effect. This is believed due to the mixing between hemispheres via the corpus callosum, and suggests a possible means of assessing the role of the corpus callosum.

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID

摘要:

ABSTRACTA technique is described which will enable an optometrist to perform an adequate evaluation of the visual system of an infant.

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

ISSN:0093-7002    

出版商:OVID    

年代:1975

数据来源: OVID