Stimulus deprivation amblyopia in children. Sensitivity, plasticity, and elasticity (SPE)
G. B. Jastrzebski, C. S. Hoyt and E. Marg
In the SPE model we propose, sensitivity (S) to deprivation results in
changes that may be either plastic (P) (permanent) or elastic (E)
(temporary). The effects of various levels (hours per day) of monocular
occlusion in amblyopic children are measured as the change in visual acuity
in each eye. At the patching level extremes (12 or more hours per day, zero
hours per day) the effects on visual acuity in the two eyes are reciprocal,
but nearly equal (symmetrical). At intermediate levels of occlusion, the
asymmetries in effects necessary for successful occlusion can be
demonstrated. Additional measurements of SPE parameters in children may
allow for the determination of occlusion dose response whereby the risks of
occlusion amblyopia and interference with binocularity may be avoided.