[Spatial binocular adaptation in microtropia and orthotropia. Definition and method of measurement].

For a long time the problem of the functional recovery in convergent strabismus has been a hardly debated topic. For some authors, it is very rare; for others, on the other hand, the result is frequently achieved. Such disparities seem to be chiefly related to the tests used. The authors have selected 10 binocular tests and they carried out this scale in a prospective study in 100 cases of esotropias having normal moving performances following a medico-surgical management and in 20 normal cases. statistical correlations reveal that there is a very large disparity of "good answers" according to the tests; but there is no redundancy at all between them. Consequently for a relevant check up every single one is necessary. The total of "good scores" and differential values of ten tests allow to know the true state of binocular spatial adaptation. The statistical analysis shows that in secondary microtropias and orthotropias there is almost always an actual binocular spatial adaptation. Its level may be high, medium or low. The high margin is clearly different from the binocular scores in normal cases. Two events are very uncommon: a full recovery of binocular vision and the opposite condition of its complete suppression. The results of such a method give a clear explanation of conflicting opinions about the binocular evolution of convergent squints following medical and surgical management.