19. In primary position muscle plane of the SR forms angle 23°with optical axis. In this position SR Elevates the globe. Secondary Actions intorsion and adduction
20.
21. In 23° abduction, SR complete Elevator, muscle plane coincides with optical axis
22.
23. Eye in primary position Muscle plane SO forms angle 54° with optical axis. Action is intorsion Secondary actions abduction and depression RE
24. When globe adducted 54°, Optical axis and muscle plane coincide, SO is pure depressor RE
The condition in which the patient sees not much and the practitioner nothing at all… ! It is always (or almost always) associated with strab, aniso or form deprivation in early life. Diagnosed when there reduced letter acuity, absence of pathology and when any ametropia is corrected. The results of pyschophysical studies & electrophysiological investigations suggest little primary retinal or LGN abnormality. Instead, the most profound effects of the amblyopic process are found in the striate cortex.