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Biomedical subjects

W W Somers

Publications and source records attributed to W W Somers.

6 recordsLinked to original sources
PubMed1984

Estimation of the stereoscopic threshold utilizing perceived depth.

Recent reports in the literature indicate that a random-dot style of stereoscopic test is the most accurate method of assessing stereoscopic threshold [Cooper, J., Feldman, J. and Medlin, D. (1979) J. Am. optom. Ass. 50, 821-825]. While this is undoubtedly true for those who can respond to the test, it is less so for very young, infirm or other patients who do not or cannot have the requisite attention span. This experiment finds that the amount of perceived depth seen on a test like the Titmus fly correlates very accurately with the measured stereoscopic threshold and can therefore be used as a measure of the threshold without having to employ the entire testing procedure of the random dot tests. The regression equation derived from the data is presented, as well as a table that allows a practitioner to estimate the stereoscopic threshold from the amount of perceived depth on a common stereo test: the Titmus fly.

Adult↗
PubMed1984

Use of a personal microcomputer for orthoptic therapy.

Personal microcomputers have become almost commonplace in the last few years. Their great flexibility and ability to present graphic images on demand would seem to make them ideal tools for use in a visual training program. We have written such a program for doing fusional vergence therapy that interacts with the patient and stores the results of the training sessions. The features of the program are described and the results from two patients are summarized.

Accommodation, Ocular↗
PubMed1984

Binocular balance validity: a comparison of five common subjective techniques.

For most patients, one of the last steps in the subjective determination of the refractive error is the equalization of their accommodative stimuli. Several previous authors have stated that the preferred method of balancing is by some form of binocular stimulation, either with a Turville infinity balance or a polarizing technique [Miles, P. (1948) Am. J. Ophthal . 31, 1460-1466; Morgan, M. W., Jr (1949) Am. J. Optom . 26, 231-239; Goodwin, H. E. (1966) Optom . Wkly 57, 28, 47-51; Grentsch , L. W. and Goodwin, H. E. (1966) Am. J. Optom . 43, 658-663]. This experiment looks at a slightly different aspect: how repeatable a given technique is. We performed five common methods of balancing: vectographic , equal acuity through low plus blur, red-green equalization, Jackson cross-cylinder, and equal loss of acuity with plus blur. We find no significant differences in the variation of any of these techniques; they are all equally reliable. In addition, there seems to be no difference in their mean values, contrary to previous reports.

Accommodation, Ocular↗