Hyperphoria and Cyclophoria
Hyperphoria is a potential deviation of one eye upwards which becomes an actual deviation when the two eyes are dissociated, and which recovers when the dissociating factors are removed. In…
Exophoric Conditions
Although it has been shown that divergence is actively stimulated ( Breinin, 1957 ), exophoria appears to be a much more passive condition than esophoria. There are several potential explanations…
Esophoric Conditions
Most esophoria is ‘accommodative’, in that it largely results from excessive accommodation due to uncorrected hypermetropia or prolonged close work. As a result of the accommodation/convergence linkage, the overactive accommodation…
Management of Heterophoria: Basic Principles
Before dealing with the individual heterophoric conditions in the next three chapters, this chapter outlines the basic principles of management. There are two reasons to treat a heterophoria: to alleviate…
Binocular Instability
A heterophoria is compensated when the vergence system can adequately overcome the heterophoria. Yet there are subjects with a negligible heterophoria and whose opposing fusional reserves meet the conventional criteria…
Detecting Binocular Vision Anomalies in Primary Eyecare Practice
Introduction The routine for examining the eyes and vision of every patient in primary eyecare should have three objectives: to detect the presence of anomalies, indicate when further investigative tests…
Examination of Young Children
Objectives In examining the eyes and vision of preschool children, under the age of 4–5 years, the approach and method should be modified from the routine appropriate to older children…
Nature of Binocular Vision Anomalies
Introduction Binocular vision is the coordination and integration of what is received from the two eyes separately into a single binocular percept. Proper functioning of binocular vision without symptoms depends…
